Phases Of Hair Growth

Fingernails provide protection to the fingertips, enhance sensation, and allow small objects to be grasped. The underlying nail bed is part of the nail matrix containing blood vessels, nerves, and melanocytes and has parallel rete ridges. The nail plate is formed from matrix keratinocytes. Fingernails grow at an average rate of 0.1 mm per day, two to three times faster than the rate of toenail growth. For example, arsenic poisoning may cause a horizontal hypopigmentation across all nail plates known as Mees lines.

Nail psoriasis

Nail psoriasis can cause nail denting or crumbling.

Causes

People living with psoriasis may develop symptoms. It occurs when psoriasis affects the skin of the nail bed or near the nail beds.

Symptoms

⦁ crumbling nails pitting
⦁ changes in color to yellow or brown
⦁ a build-up of skin under the nails
⦁ blood under the nails
⦁ the nail separates from the bed

Brittle splitting nails

Brittle splitting nails, or onychoschizia, is a common issue that dermatologists see. The condition can cause brittle, soft, splitting, or thin nails.

Causes

Common causes of brittle nails are repeatedly wetting and drying the nails. Though less common, other causes may include iron deficiency or underlying illness.

Symptoms

The most common symptom is that the nails break easily. The American Osteopathic College of Dermatology state people can often tell if the cause is internal, as the condition affects both fingernails and toenails. If there is an external cause, symptoms will typically only affect the fingernails.

Onychogryphosis

Onychogryphosis is a condition where the nail becomes overgrown and thick, often affecting the big toe. It can cause one portion of the nail to grow longer than the other part.

Causes

Potential causes of onychogryphosis include: ⦁ genetics ⦁ injury ⦁ circulation issues ⦁ psoriasis ichthyosis

Symptoms

When a person has onychogryphosis, the nail grows very thick. In other cases, a portion of the nail may grow larger than the other part. The growth can resemble a ram’s horn, so people often refer to it as Ram’s horn nails

Ingrown toenails 

An ingrown toenail can cause pain and swelling, and in some cases, they can become infected.

Causes

According to the American Academy of Orthopaedic Surgeons, genetics may play a role in the development of ingrown toenails. Also, there are other potential causes, including: ⦁ not keeping nails trimmed ⦁ wearing tight socks or shoes ⦁ physical injury

Symptoms

Symptoms can include: ⦁ swelling and tenderness ⦁ redness ⦁ soreness pus

Nail fungal infections

Nail fungal infections are a common condition that causes the nails to become thick, discolored, and easier to break. Nail fungus is more common in the toes than fingers.

Causes

Several different types of molds and fungus can affect nails. They grow when a crack or break traps fungi between the nail and the nail bed. Sweat, athlete’s foot, and salon manicures and pedicures can put people at higher risk of nail fungal infections.

Symptoms

Symptoms include: ⦁ thick nails ⦁ discolored nails that are brown, yellow or white ⦁ fragile or cracked nails Fungus under the nails often is not painful

Onycholysis 

Onycholysis is when the toe or fingernail painlessly separates from the nail bed. It typically occurs slowly over time and could result from an underlying health condition or injury.

Causes

The most common cause is from local injury to the nail. Other triggers include: ⦁ excessive filing ⦁ exposure to chemicals ⦁ allergic ⦁ contact dermatitis ⦁ submersion in water Psoriasis, fungal infections, and reactions to certain medications are also common causes.

Symptoms

The main symptom of onycholysis is the separation of the nail from the nail bed. This can result in discoloration of the nail, turning it green, yellow, or opaque. It can also cause additional skin tissue under the nail, nail pitting, nail thickening, or bending of the nail edges.

Paronychia 

Paronychia is an infection that causes redness and swelling around the edges of a nail bed.

Causes

There are two types of paronychia: acute and chronic. Acute paronychia occurs when there is an infection due to direct or indirect trauma to the cuticle or nail fold. Chronic paronychia is often the result of allergens or irritants.

Symptoms

Acute paronychia symptoms can include:
⦁ swelling
⦁ pain
⦁ redness 
⦁ fever and gland pain in severe cases
⦁ yellow pus
Chronic paronychia often starts on one nail and spreads to others. The nail folds may have the following symptoms:
⦁ redness 
⦁ pain
⦁ swelling
⦁ yellow or green pus
⦁ lifting of the nail from the bed
⦁ tenderness

Dermis is the inner layer of the skin. It is an integrated system of fibrous, filamentous, and amorphous connective tissue that accommodates stimulus induced entry by nerve and vascular networks, epidermally derived appendages, fibroblasts, macrophages, and mast cells. It is a connective tissue layer, made up of dense and stout collagen fiber fibroblasts and histiocytes. Collagen fibers exhibit elastic property and are capable of storing or holding water. Collagen fibers contain the enzyme collagenase, which is responsible for wound healing. The dermis lies on the subcutaneous tissue, or panniculus, which contains small lobes of fat cells known as lipocytes. The thickness of these layers varies considerably, depending on the geographic location on the anatomy of the body. The eyelid, for example, has the thinnest layer of the epidermis, measuring less than 0.1 mm, whereas the palms and soles of the feet have the thickest epidermal layer, measuring approximately 1.5 mm. The dermis is thickest on the back, where it is 30–40 times as thick as the overlying epidermis. The dermis comprises the bulk of the skin and provides its pliability, elasticity, and tensile strength. It protects the body from mechanical injury, binds water, aids in thermal regulation, and includes receptors of sensory stimuli.

LAYERS OF DERMIS

Dermis is made up of two layers: 1. Superficial papillary layer 2. Deeper reticular layer.

SUPERFICIAL PAPILLARY LAYER -

It projects into the epidermis. It contains blood vessels, lymphatics and nerve fibers. This layer also has some pigment containing cells known as chromatophores. Dermal papillae are finger like projections, arising from the superficial papillary dermis. Each papilla contains a plexus of capillaries and lymphatics, which are oriented perpendicular to the skin surface.

RETICULAR LAYER -

It is made up of reticular and elastic fibers. These fibers are found around the hair bulbs, sweat glands and sebaceous glands. The reticular layer also contains mast cells, nerve endings, lymphatics, epidermal appendages and fibroblasts. Immediately below the dermis, subcutaneous tissue is present. It is a loose connective tissue, which connects the skin with the internal structures of the body. It serves as an insulator to protect the body from excessive heat and cold of the environment.

1. PROTECTIVE FUNCTION

2. SENSORY FUNCTION

3. STORAGE FUNCTION

4. SYNTHETIC FUNCTION

5. REGULATION OF BODY TEMPERATURE

6. REGULATION OF WATER AND ELECTROLYTE BALANCE

7. EXCRETORY FUNCTION

8. ABSORPTIVE FUNCTION

9. SECRETORY FUNCTION

PROTECTIVE FUNCTION -

Skin forms the covering of all the organs of the body and protects these organs from the following factors: i. Bacteria and toxic substances ii. Mechanical blow iii. Ultraviolet rays.

SENSORY FUNCTION -

Skin is considered as the largest sense organ in the body. It has many nerve endings, which form the specialized cutaneous receptors These receptors are stimulated by sensations of touch, pain, pressure or temperature sensation and convey these sensations to the brain via afferent nerves. At the brain level, perception of different sensations occurs.

STORAGE FUNCTION -

Skin stores fat, water, chloride and sugar. It can also store blood by the dilatation of the cutaneous blood vessels.

SYNTHETIC FUNCTION -

Vitamin D3 is synthesized in skin by the action of ultraviolet rays from sunlight on cholesterol

REGULATION OF BODY TEMPERATURE -

Skin plays an important role in the regulation of body temperature. Excess heat is lost from the body through skin by radiation, conduction, convection and evaporation. Sweat glands of the skin play an active part in heat loss, by secreting sweat. The lipid content sebum prevents loss of heat from the body in cold environment.

REGULATION OF WATER AND ELECTROLYTE BALANCE -

Skin regulates water balance and electrolyte balance by excreting water and salts through sweat.

EXCRETORY FUNCTION -

Skin excretes small quantities of waste materials like urea, salts and fatty substance.

ABSORPTIVE FUNCTION -

Skin absorbs fat-soluble substances and some ointments.

SECRETORY FUNCTION -

Skin secretes sweat through sweat glands and sebum through sebaceous glands. By secreting sweat, skin regulates body temperature and water balance. Sebum keeps the skin smooth and moist.

SKIN AS A WHOLISM

PSYCHONEUROIMMUNO DERMATOLOGY

SKIN TYPES AS A PERSONALITY REFLECTION

	Clinical Features	Other Notable Features	Histologic Features
Psoriasis	Sharply demarcated, erythematous plaques with mica-like scale; predominantly on elbows, knees, and scalp; atypical forms may localize to intertriginous areas; eruptive forms may be associated with infection	May be aggravated by certain drugs, infection; severe forms seen in association with HIV	Acanthosis, vascular proliferation
Lichen planus	Purple polygonal papules marked by severe pruritus; lacy white markings, especially associated with mucous membrane lesions	Certain drugs may induce: thiazides, antimalarial drugs	Interface dermatitis
Pityriasis rosea	Rash often preceded by herald patch; oval to round plaques with trailing scale; most often affects trunk; eruption lines up in skinfolds giving a “fir tree–like” appearance; generally spares palms and soles	Variable pruritus; self-limited, resolving in 2–8 weeks; may be imitated by secondary syphilis	Pathologic features often nonspecific
Dermatophytosis	Polymorphous appearance depending on dermatophyte, body site, and host response; sharply defined to ill-demarcated scaly plaques with or without inflammation; may be associated with hair loss	KOH preparation may show branching hyphae; culture helpful	Hyphae and neutrophils in stratum corneum

1. Alopecia:

Hair loss, partial or complete.

2. Annular:

Ring-shaped

3. Cyst:

A soft, raised, encapsulated lesion filled with semisolid or liquid contents

4. Herpetiform:

In a grouped configuration.

5. Lichenoid eruption:

Violaceous to purple, polygonal lesions that resemble those seen in lichen planus.

6. Morbilliform rash:

Generalized, small erythematous macules and/or papules that resemble lesions seen in measles.

7. Nummular:

Coin-shaped.

8. Polycyclic lesions:

A configuration of skin lesions formed from coalescing rings or incomplete rings.

9. Pruritus:

A sensation that elicits the desire to scratch. Pruritus is often the predominant symptom of inflammatory skin diseases (e.g., atopic dermatitis, allergic contact dermatitis); it is also commonly associated with xerosis and aged skin. Systemic conditions that can be associated with pruritus include chronic renal disease, cholestasis, pregnancy, malignancy, thyroid disease, polycythemia vera, and delusions of parasitosis.

Diagnosis	Common Distribution	Usual Morphology	Diagnosis	Common Distribution	Usual Morphology
Acne vulgaris	Face, upper back, chest	Open and closed comedones, erythematous papules, pustules, cysts	Seborrheic keratosis	Trunk, face	Brown plaques with adherent, greasy scale; “stuck on” appearance
Rosacea	Blush area of cheeks, nose, forehead, chin	Erythema, telangiectases, papules, pustules	Folliculitis Impetigo	Any hair-bearing area Anywhere	Follicular pustules Papules, vesicles, pustules, often with honey-colored crusts
Seborrheic dermatitis	Scalp, eyebrows, perinasal areas	Erythema with greasy yellow-brown scale	Herpes simplex	Lips, genitalia	Grouped vesicles progressing to crusted erosions
Atopic dermatitis	Antecubital and popliteal fossae; may be widespread	Patches and plaques of erythema, scaling, and Lichenification; pruritus	Herpes zoster	Dermatomal, usually trunk but may be anywhere	Vesicles limited to a dermatome (often painful)
Stasis dermatitis	Ankles, lower legs over medial malleoli	Patches of erythema and scaling on background of hyperpigmentation associated with signs of venous insufficiency	Varicella	Face, trunk, relative sparing of extremities	Lesions arise in crops and quickly progress from erythematous macules, to papules, to vesicles, to pustules, to crusted sites.
Dyshidrotic eczema	(Pompholyx) Palms, soles, sides of fingers and toes	Deep vesicles	Pityriasis rosea	Trunk (Christmas tree pattern); herald patch followed by multiple smaller lesions	Symmetric erythematous patches with a collarette of scale
Allergic contact dermatitis	Anywhere	Localized erythema, vesicles, scale, and pruritus (e.g., fingers, earlobes—nickel; dorsal aspect of foot—shoe; exposed surfaces—poison ivy)	Tinea versicolor	Chest, back, abdomen, proximal extremities	Scaly hyper- or hypopigmented macules
Psoriasis	Elbows, knees, scalp, lower back, fingernails (may be generalized)	Papules and plaques covered with silvery scale; nails have pits	Candidiasis	Groin, beneath breasts, vagina, oral cavity	Erythematous macerated areas with satellite pustules; white, friable patches on mucous membranes
Lichen planus	Wrists, ankles, mouth (may be widespread)	Violaceous flat-topped papules and plaques	Dermatophytosis	Feet, groin, beard, or scalp	Varies with site, (e.g., tinea corporis—scaly annular plaque)
Keratosis pilaris	Extensor surfaces of arms and thighs, buttocks	Keratotic follicular papules with surrounding erythema	Scabies	Groin, axillae, between fingers and toes, beneath breasts	Excoriated papules, burrows, pruritus
Melasma	Forehead, cheeks,temples, upper lip	Tan to brown patches	Insect bites	Anywhere	Erythematous papules with central puncta
Vitiligo	Periorificial, trunk, extensor surfaces of extremities, flexor wrists, axillae	Chalk-white macules	Cherry angioma Keloid Dermatofibroma	Trunk Anywhere (site of previous injury) Anywhere	Red, blood-filled papules Firm tumour, pink, purple, or brown Firm red to brown nodule that shows dimpling of overlying skin with lateral compression
Actinic keratosis	Sun-exposed areas	Skin-colored or red-brown macule or papule with dry, rough, adherent scale	Acrochordons (skin tags)	Groin, axilla, neck	Fleshy papules
Basal cell carcinoma	Face	Papule with pearly, telangiectatic border on sun-damaged skin	Urticaria	Anywhere	Wheals, sometimes with surrounding flare; pruritus
Squamous cell carcinoma	Face, especially lower lip, ears	Indurated and possibly hyperkeratotic lesions often showing ulceration and/or crusting	Transient acantholytic dermatosis Xerosis	Trunk, especially anterior chest Extensor extremities, especially legs	Erythematous papules Dry, erythematous, scaling patches; pruritus

DISEASE OF SKIN

PAPULOSQUAMOUS DISORDERS

	Clinical Features	Other Notable Features	Histologic Features
Psoriasis	Sharply demarcated, erythematous plaques with mica-like scale; predominantly on elbows, knees, and scalp; atypical forms may localize to intertriginous areas; eruptive forms may be associated with infection	May be aggravated by certain drugs, infection; severe forms seen in association with HIV	Acanthosis, vascular proliferation
Lichen planus	Purple polygonal papules marked by severe pruritus; lacy white markings, especially associated with mucous membrane lesions	Certain drugs may induce: thiazides, antimalarial drugs	Interface dermatitis
Pityriasis rosea	Rash often preceded by herald patch; oval to round plaques with trailing scale; most often affects trunk; eruption	Variable pruritus; self-limited, resolving in 2–8 weeks; may be	Pathologic features often nonspecific
	lines up in skinfolds giving a “fir tree–like” appearance; generally spares palms and soles	imitated by secondary syphilis
Dermatophytosis	Polymorphous appearance depending on dermatophyte, body site, and host response; sharply defined to illdemarcated scaly plaques with or without inflammation; may be associated with hair loss	KOH preparation may show branching hyphae; culture helpful	Hyphae and neutrophils in stratum corneum

one of the most common chronic, noncontagious, dermatologic diseases, affecting up to 2% of the world’s population. It is an immune-mediated disease clinically characterized by an unpredictable course of remissions and relapses and presence at typical sites of well- defined erythematous, sharply demarcated papules and rounded plaques covered by silvery micaceous scale. The skin lesions of psoriasis are variably pruritic. Traumatized areas often develop lesions of psoriasis (the Koebner or isomorphic phenomenon). There is frequent nails and joint involvement.

EPIDEMIOLOGY

1. GENETIC FACTOR- Some HLA markers like HLA-CW6 carries very high risk and HLA -B13 and HLA – B17.
2. DRUGS – Lithium carbonate and Propranolol due to their inhibiting action on adenyl cyclase altering epidermal cell kinetics may cause psoriasis.
3. INFECTION – Psoriatic lesion have been seen in children after sore throat caused by beta – haemolytic streptococci.
4. TRAUMA – Repeated trauma over the elbow and knee may explain the site of psoriasis.
5. MENTAL STRESS
ETIOLOGY

1. Disturbed fat metabolism
2. Hormonal imbalance
3. Septic focus
4. Allergy
5. Anxiety
6. Stress
7. Hereditary influences

TYPE OF PSORIASIS
1. Plaque – The most common form of psoriasis, causes dry, raised, red skin lesions (plaques) covered with silvery scales. The plaques itch or may be painful and can occur anywhere on your body. 

2. Guttate – It is seen in children and young adults where raindrop like lesion develops. It is a type of ⦁ psoriasis that presents as small (0.5–1.5 cm in ⦁ diameter) ⦁ lesions over the ⦁ upper trunk and ⦁ proximal extremities; it is found frequently in young adults.

3. Inverse- It is a form of ⦁ psoriasis that selectively, and often exclusively, involves the folds, recesses, and flexor surfaces such as the ⦁ ears, ⦁ axillae, ⦁ groin folds, ⦁ inframammary folds, ⦁ navel, ⦁ intergluteal cleft, ⦁ penis, lips, and webspaces.
4. Pustular - The term pustular psoriasis is used for a heterogeneous group of diseases that share pustular skin characteristics. It can be localized, commonly to the hands and feet (⦁ localized pustular psoriasis), or generalized with widespread patches appearing randomly on any part of the body (⦁ generalized pustular psoriasis). Scaling is very much prominent and nail changes including thickening and colour changes are very common.

5. Erythrodermic – It represents a form of ⦁ psoriasis that affects all body sites, including the face, hands, feet, nails, trunk, and extremities. This specific form of psoriasis affects 3 percent of persons diagnosed with psoriasis.

SYMPTOMS

1. Initial lesion consists of red spots which vary in sizes and may appear in any part of body.
2. They are popular lesions which are covered with silvery scales which after scraping leave behind a shiny bleeding surface.(Auspitz sign).
3. Itching is usually absent but may be present when lesions are in the body folds and on vulva.
4. Psoriatic lesions may develop in the line of scratch during its active phase known as Koebner’s phenomenon.
5. The nails may also become thickened, pitted and striated.

PSORIASIS MEDICINES
1. GRAPHITES – Complaints from grief and vexation; suppression of skin eruptions; extremes of heat and cold. There is obstinate dryness of the skin. Eruption oozes out thick, sticky, honey like exudation. Unhealthy skin, every little injury suppurates. Severe itching on the surface of skin. Scabby eruption. Worse – warmth, night, during and after menstruation. Better – dark, from wrapping up.

2. SULPHUR – Complaints from alcohol, sun’s heat, suppression of skin diseases, over exertion. Dry, scaly, unhealthy skin, every little injury suppurates. Itching, burning, worse scratching and washing. Exanthema in general on any part of body which is < by heat, warmth at work. Tetters of a greenish yellow colour with itching. Worse – Standing, at rest, washing, warmth of bed and changeable weather. Better – Open air, motion, lying on right side and sweating.

3. CUPRUM ARS – skin is very sensitive to touch, pressure < all symptoms.

4. ANTIMONIUM CRUDDUM – Complaints from disappointed love, cold bathing, alcohol, fat, fruits, suppressed eruptions, extremes of heat and cold. Thick hard honey coloured scabs. Itching when warm in bed. Dry skin, scaly, pustular eruption with burning and itching < night. Concomitant - There are eruption with gastric derangement.
Worse – evening, heat, acids, water, washing
Better – open air, during rest, moist warmth.

5. STAPHISAGRIA - Complaints from onanism, sexual excess, sexual abuse, loss of vital fluids. There is yellowish, acrid moisture oozes out, forming crusts over it. Thick scabs, dry and itch violently scratching changes location of itching. Exanthema on cheeks, face, yellow with a creeping itching.
Worse – mental affection, anger, indignation, grief, onanism.
Better -

The term eczema means “to boil out”, because it seems that the skin is "boiling out" or "oozing out" in eczema.

Eczema is a type of dermatitis. It is a reaction pattern that has two components:

1. Clinical component

2. Histological component

Clinical Component - Eczema, clinically manifests as pruritus, erythema, edema, papule, vesicles, scaling and Lichenification.The feature that predominates depends on the stage – acute eczema is exudative, while chronic eczema is dry, scaly, and often lichenified.

Histological Component - the hallmark of eczema is spongiosis. In the chronic stage, the lesion shows hyperkeratosis and acanthosis. Primary lesions may include erythematous macules, papules, and vesicles, which can coalesce to form patches and plaques. Secondary lesions from infection or excoriation, marked by weeping and crusting, may predominate. In chronic eczematous conditions, Lichenification (cutaneous hypertrophy and accentuation of normal skin markings) may alter the characteristic appearance of eczema.

ETIOLOGICAL CLASSIFICATION

.

ENDOGENOUS	EXOGENOUS	COMBINED
Seborrheic dermatitis	Irritant dermatitis	Atopic dermatitis
Nummular dermatitis	Allergic dermatitis	Pompholyx
Lichen simplex	chronicus Photodermatitis
Pityriasis alba	Radiation dermatitis
Stasis dermatitis	Infective dermatitis

CLASSIFICATION OF ECZEMA

.

ETIOLOGY	PATTERN/MOROHOLOGY	CHRONICITY
Endogenous	Discoid	Acute
Exogenous	Hyperkeratotic	Chronic
Combined	Lichenified
	seborrheic

The most practical way to classify eczema, according to etiology is:

1. Endogenous eczema: Where constitutional factors predispose the patient to developing an eczema.
2. Exogenous eczema: Where external stimuli trigger development of eczema, e.g., irritant dermatitis.
3. Combined eczema: When a combination of constitutional factors and extrinsic triggers are responsible for the development of eczema e.g. atopic dermatitis.


CLINICAL FEATURES
The clinical features of eczema depend on the stage of the disease :

1. ACUTE
2. CHRONIC

Acute Eczema
– It is characterized by erythematous and oedematous plaque, which is ill – defined and is surmounted by papules, vesicles, pustules and exudate that dries to form crusts

Chronic Eczema - It is characterized by Lichenification, which is a triad of hyperpigmentation, thickening oof skin and increased skin markings. The lesions are less exudative and more scaly.

POINT OF DIAGNOSIS

1. Acute eczema – Itchy exudative plaques, surmounted by papulovesicles.
2. Chronic eczema – Lichenified scaly plaques

1) GRAPHITES- Complaints from grief and vexation; suppression of skin eruptions; extremes of heat and cold. The eruption is crusty, moist, yellow and sticky; especially forming in the folds of joints such as the elbows, knees or groin. The skin can become very dry, cracked, red, itchy and painful. Eczematous and herpetic eruption predominate. Eczema of ears and moist eczema round anus

Worse – warmth, night, during and after menstruation
Better – dark, from wrapping up.

2) CICUTA VIROSA - Complaints from nervous irritation, worms, suppressed eruption, shock and injury. Burning itching over the whole body. Purulent eruption with yellowish and burning scabs. The eczema forms thick yellow scabs (like dried honey) and affects the cheeks, chin and scalp where it is burning and itchy.

Worse – touch, draught, tobacco smoke.
Better – rest, dark room.

3) RHUS TOX – Complaints from spraining and straining, over lifting, from wetting, summer bathing in lake or river, getting wet when heated. Red, swollen, itching intense. Vesicles, herpes, vesicular suppurative forms. Burning eczematous eruptions with tendency to scale formation.

Worse – during sleep, cold, wet rainy weather and after rain, during rest
Better – warmth, dry weather, motion, walking, rubbing, warm application.

4) LYCOPODIUM – Complaints from fright, anger, mortification, or vexation with reserved displeasure. Chronic eczema associated with urinary, gastric and hepatic disorders; bleed easily. Skin becomes thick and indurated. It is used for eczema that is bleeding, moist or discharging; affecting the scalp, armpits, limbs, back and neck.

Worse –4 – 8 p.m., right side, from heat, warm air
Better – warm food and drinks, uncovering the head, open air.

5) BOVISTA – Unhealthy skin. The eczema may be either dry or moist, with thick crust formed by very thick, tough, stringy and tenacious discharges from the eruption.

Worse –on waking up in the morning and after bathing.
Better – after meals.

The word “atopy” means “no (without) place” was first used for a group of hereditary disorders in people who had a tendency to develop an urticarial response to foods and inhaled substances. It is a chronic inflammation of the epidermis and dermis, characterized by a family history of asthma, allergic rhinitis, or eczema.

It is and endogenous eczema triggered by exogenous agents and characterized by :
1) Extremely pruritic, recurrent, symmetric eczematous lesions.
2) Personal and family history of atopic diathesis.
3) Increased ability to form IgE to common environmental allergens

Seborrheic dermatitis is a common, chronic disorder characterized by greasy scales overlying erythematous patches or plaques. Induration and scale are generally less prominent than in psoriasis, but clinical overlap exists between these diseases (“sebopsoriasis”).
ETIOLOGY

1. Microbial etiology – overgrowth of yeast, MALASSEZIA FURFUR may play a part in the development of seborrheic dermatitis.
2. Genetic predisposition
3. Immunodeficiency

EPIDEMIOLOGY
1. Prevalence - fairly common if all the patient with mild dandruff. Incidence of SD is very common in HIV – positive patient.
2.Age – most common in adults.
3.Gender – More common in males.

SITE
1. The most common location is in the scalp, where it may be recognized as severe dandruff (“cradle cap”).
2. On the face, seborrheic dermatitis affects the eyebrows, eyelids, glabella, nasolabial folds, retroauricular aarea, interscapular regions.
3. Scaling of the external auditory canal is common in seborrheic dermatitis.
4. It may also develop in the central chest, axilla, groin, submammary folds, and gluteal cleft

Contact dermatitis is an inflammatory skin process caused by an exogenous agent or agents that directly or indirectly injure the skin. It is the reaction of the skin to the contactants.

TYPES

IRRITANT ALLERGIC
In IRRITANT CONTACT DERMATITIS (ICD), this injury is caused by an inherent characteristic of a compound—for example, a concentrated acid or base.

ETIOLOGY
1. Occupational exposure, either industrial contact or as a household contact.
2. Airborne exposure, costume jewellery, hair dyes, cosmetics, topical antibiotics, local anesthetics.

PREDISPOSING FACTORS
1). Dry skin is more susceptible to irritant dermatitis.
2). Atopic individual are more susceptible.
3). SITE – face, scrotum and back of the hands is more susceptible while skin of palms and soles is resistant.
4. Protective measures reduces the rate of ICD.


CLINICAL FEATURES
1. Little dryness, redness or chapping to various types of eczematous dermatitis to an acute caustic burn.
2. Acute exudative lesions – If the exposure is to a strong irritant.
3. Dry dermatitic lesions – If there is chronic repeated exposure to a weal irritant.
4. The clinical lesions of contact dermatitis may be acute (wet and oedematous) or chronic (dry, thickened, and scaly), depending on the persistence of the insult
ALLERGIC CONTACT DERMATITIS
Agents that cause ACD induce an antigen-specific immune response (e.g., poison ivy dermatitis).

ETIOLOGY Common allergens are plants (parthenium), metals (nickel), cosmetics (hair dyes and fragrances), medicines and rubber.

PATHOGENESIS

Develop due to involvement of immunological pathway, being a type IV reaction to exogenous contact antigens. It does not develop on the first exposure because patients immunological pathway has not been sensitized

It is a papulosquamous disorder that may affect the skin, scalp, nails, and mucous membranes. It is flat topped inflammatory erythematous or purplish papules showing a criss – cross appearance of the surface often seen on the flexor surface of the skin with symmetric distribution along with lacy lesions of buccal mucesa. The skin lesions may occur anywhere but have a predilection for

ETIOLOGY 1). Nervous and Mental tension
2). Trauma


PATHOLOGY
At the epidermo – dermal junction band – like infiltration of melanophage, histiocyte is seen . At the same site immunoglobulin mainly IgM deposits are seen.

SITES –
1. Lesions are most frequently seen on extremities and lower back.
2. Lesions may appear at the sites of trauma.
3. Lesions may appear on wrists, shins and genital

VARIANT	CHANGE	MORPHOLOGY	SITES OF PREDILECTION
ANNULAR		Hyperpigmented flat center. Violaceous elevated periphery.	Face, glans penis.
ACTINIC		Annular lesions with thready edge. Perilesional hypopigmented halo.	Face, dorsal/ dorsolateral aspect of upper extremities.
LINEAR		Papules arranged linearly	Extremities
FOLLICULAR		Perifollicular violaceous papules leading to cicatricial alopecia.	Scalp, trunk,medial aspect of extremities.
HYPERTROPHIC		Central depigmentation. Verrucous hyperkeratotic papules and nodules.	Shins
BULLOUS		Lesion on LP. Bulla	Extremities

CLINICAL FEATURES

Age – Young adults and children.
Onset – acute or insidious.
1). The primary cutaneous lesions are pruritic, polygonal, pleomorphic papules which are very small violaceous papules on flexor aspect of upper or lower limbs, over the axillae and on the abdomen, forearms, wrists, legs, genitalia and on face symmetrically.
2). Papule may enlarge with cleaning of the centre called lichen planus annularis .
3). It develop a network of Gray lines (Wickham’s striae) and shiny waxy appearance may also be seen.
4). Mucous membrane is involved with bluish patches are seen.
5). Moderate to severe itching is always present.
6). The triad of diagnosis is typical skin lesions, typical mucosal lesion and typical histopathologic findings.

POINT OF DIAGNOSIS
1). Itchy violaceous, polygonal flat topped papules with characteristic Wickham’s striae on the surface.
2). Typical sites of involvement.
3). Oral lesion – lacy reticulate lesions.
4). Nail changes – Thinning of nail plate and pterygium corroborate diagnosis.

Pityriasis rosea (PR) is a papulosquamous eruption of unknown etiology occurring more commonly in the spring and fall. This is followed in a few days to a few weeks by the appearance of many smaller annular or papular lesions with a predilection to occur on the trunk. Individual lesions may range in color from red to brown and have a trailing scale.
ETIOLOGY
1. Self – limiting condition (2-10 weeks).
2. Caused by virus - HHV - 739 MORE FREQUENTLY
3. It is non – contagious.

EPIDEMIOLOGY
1. Age – usually between ages 10 - 3 5 years.
2. Season - Incidence lowest in summer.

CLINICAL FEATURES
EVOLUTION
HERALD PATCH
MANY SIMILAR LESIONS, WHICH ANLARGE SLOWLY
MILD PIGMENTARY CHANGE

FADES SLOWLY
1. Itching, usually mild.
2. HERALD PATCH – it is the first lesion of pityriasis rosea and is seen in sbout 80% of patients.
3. Oval lesions with wrinkled, salmon pink centre and collarette of scales at the periphery.
4. SECONDARY LESION – begin as scaly papules, which enlarge to form oval annular plaques similar to herald patch.
5. They are arranged characteristically along the long axis of patches run downwards and outwards from the spine, along the lines of ribs.

TYPES

.
1. INVERSE PR.
2. PAPULAR PR.
3. BULLOUS PR

POINT OF DIAGNOSIS
1. Presence of herald patch.
2. Eruption consisting of erythematous, oval annular plaques with a peripheral collarette of scales.
3. Typical distribution on the trunk.

PITYRIASIS ROSEA
1. CALCAREA HYPO –
2. RHUS TOX – Complaints from spraining and straining, over lifting, from wetting, summer bathing in lake or river, getting wet when heated. Red, swollen, itching intense. Erysipelas vesicular eruptions, vesicles are yellow, from left to right, with much swelling, inflammation, burning, itching and stinging erysipelatous and oedematous.
Worse – during sleep, cold, wet rainy weather and after rain, during rest
Better – warmth, dry weather, motion, walking, rubbing, warm application.
3. SEPIA – Complaints from cold, laundry work, alcohol, tobacco, wetting before and during menses, after eating. Itching not relieved by scratching; is apt to change into burning, worse in bends of elbows and knees.
Worse – evening, washing, left side, after sweat.
Better – exercise, pressure, warmth of bed, hot application.
4. ARSENIC ALBUM – Complaints from Chewing tobacco, alcoholism, sea bathing, sausage poisoning, Chill, cold fruit. Itching, dry, rough and scratching of skin. There may be pustules, vesicles, desquamation from head to foot. Burning and itching followed by pain after scratching.
Worse – cold drinks, food, cold air, alcohol.
Better – hot application, warm food and drink, motion, sitting erect.

It is an intraepidermal bullous disorder, which is associated with substantial mortality and morbidity and characterized clinically by presence of cutaneous and mucosal blisters and histologically by acantholysis, which occurs due to the deposition of intercellular autoantibodies.
ETIOLOGY –
1. Idiopathic autoimmune phenomenon – it is an autoimmune disorder characterized by the presence of IgG autoantibodies against desmogleins (Dsg)5 (present in desmosomes),which are involved in keratinocyte-keratinocyte adhesion. Antibodies are deposited in the intercellular area resulting in separation of keratinocytes from each other .
3. Neosplasia-induced autoimmune phenomenon: Thymoma and lymphonma.
4. Drug-induced autoimnmune phenomenon: Penicillamine, rifampicin and captopril.

CLASSIFICATION
Pemphigus is classified ( based on the level of split, clinical features and serological profile) into :

1. Pemphigus vulgaris: Where split is supra basal.
2. Pemphigus vegetans: Where split is supra basal.
3. Pemphigus foliaceus: Where split is either in granular layer or just below the horny layer.
4. Pemphigus erythematosus: Where split either in granular layer or just below the stratum corneum

Warts are cutaneous neoplasms caused by papillomaviruses. More than 100 different human papillomaviruses (HPVs) have been described. A typical wart, verruca vulgaris, is sessile, dome-shaped, and usually about a centimetre in diameter. Its surface is hyperkeratotic, consisting of many small filamentous projections.

ETIOLOGY
1). Human papilloma virus (HPV) is a DNA virus which has not been cultured in vitro.
2). Due to PCR more than 100 type of HPV has been identified.

EPIDEMIOLOGY
1). AGE
. Nongenital warts – Most frequently in children and young adults.
. Anogenital warts – in adolescents and adults, though occasionally may be seen in children.
2. TRANSMISSION
. Nongenital warts – transmitted through direct skin – to – skin contact and by auto – inoculation.
. Anogenital warts – Sexual transmission - both in heterosexual and homosexual.
Vertical transmission – Mother with anogenital warts can transmit infection to the newborn, during vaginal delivery.

Sexual transmission - both in heterosexual and homosexual.
Vertical transmission – Mother with anogenital warts can transmit infection
to the newborn, during vaginal delivery.

Warts present clinically as :
. Verruca vulgaris
. Palmoplantar warts
. Verruca plana
. Filiform warts
. Epidermodysplasia verruciformis.
. Anogenital warts.

Verruca vulgaris (common warts)
Usually asymptomatic

Morphology
Single or multiple, circumscribed, firm papules with verrucous (hyperkeratotic) dry, stippled surface.
About 60% of common warts resolve spontaneously

Palmoplantar warts
Palmoplantar warts are of two types:
⦁ Superficial palmoplantar warts.
⦁ Deep palmoplantar warts.

Superficial palmoplantar warts (mosaic warts)
Usually painless.
Morphology: Hyperkeratotic papules and plaques consisting of multiple, small warts, which are tightly packed.

Sites: Soles and less often palms.
Deep palmoplantar warts (myrmecia)

Painful (sometimes excruciatingly so!).

Morphology: Hyperkeratotic, deep seated papules, surrounded by a horny collar. Presence of black dots, representing thrombosed capillary loops).

Sites – less often on palms and on sides of fingers


Verruca plana (plane warts)

Morphology
*Multiple, slightly elevated, that smooth papules
Skin colored or darker lesions: may have an erythematous halo.
*Lesions may be arranged linearly (pseudo Koebner's phenomenon) due to auto-inoculation.

Site
Face and on dorsal aspects of hands.


Filiform warts

Morphology - Asymptomatic, thin elongated, firm projections arising from a horny base.

Site – Most frequently on face and scalp

Anogenital warts

⦁ Sexually transmitted disease.
⦁ A variety of clinical variants, e.g., condyloma acuminata, papular warts and Bowenoid papulosis.
⦁ Most frequently on the glans, perianal region, vulva, and cervix

COURSE OF WARTS
Spontaneous resolution - In healthy individuals spontaneously (30% in 6 months and 60% in 12 months) as the host mounts an immune response. When wart is spontaneously regressing, punctate area of blackish discoloration appear on surface and the wart resolves with no sequelae.

Persistent warts - Mosaic warts very recalcitrant. In immunocompromised individuals, (on immunosuppressive therapy, with lymphoreticular malignancies or with HIV infection) warts are persistent, extensive, and have an oncogenic potential.

CLINICAL FEATURES 1. Plantar warts are endophytic and are covered by thick keratin.
2. Paring of the wart will generally reveal a central core of keratinized debris and punctate bleeding points.
3. Filiform warts are most commonly seen on the face, neck, and skinfolds and present as papillomatous lesions on a narrow base.
4. Flat warts are only slightly elevated and have a velvety, non-verrucous surface. They have a propensity for the face, arms, and legs and are often spread by shaving.
5. Genital warts begin as small papilloma that may grow to form large, fungating lesions. In women, they may involve the labia, perineum, or perianal skin. In men, the lesions often occur initially in the coronal sulcus but may be seen on the shaft of the penis, the scrotum, or the perianal skin or in the urethra.
6. The risk is higher among patients immunosuppressed after solid organ transplantation and among those infected with HIV.
POINTS FOR DIAGNOSIS
Warts are diagnosed on the basis of :
. Characteristic warty appearance with a rough, dry stippled surface.
. Presence of pseudo Koebner's phenomenon, especially in plane warts.
. Typical histology.

It is a dermatophyte infection caused by 3 different types of fungi called “Microsporum, Epidermophyton and Trichophyton”. They can easily penetrate the keratinised structures and causes skin, hair and nail infection. Dermatophytes are keratinophilic fungi, living on dead keratin so in stratum corneum.
They induce inflammation in skin due to :
Permeation of their metabolic products into deeper layers.
Induction of delayed hypersensitivity.

SOURCE –
1. Zoophilic ( induce significance inflammation ) – Animal to Man
2. Anthropophilic (induce less inflammation) – Man to Man
3 Geophilic ( induce significance inflammation – Soil to Man
ETIOLOGY –
CLINICAL FEATURES ETIOLOGY –
Prototype lesion
Is an annular or arcuate lesion which spreads centrifugally.
Margin is active, showing papulovesiculation, pustulation, and scaling .
Center is relatively clear, though in chronic lesions there may be nodules, hyperpigmentation and even Lichenification in the center.
These features may be modified, depending on:
Site of infection
Strain of fungus
RINGWORM
1. ARSENIC ALBUM – Complaints from Chewing tobacco, alcoholism, sea bathing, sausage poisoning, Chill, cold fruit. Itching, dry, rough and scratching of skin. Eruptions with raised and hard edges, surrounded by a red and shining crown with bottom like lard or of a blackish – blue colour with burning pains or shooting .
Worse – cold drinks, food, cold air, alcohol.
Better – hot application, warm food and drink, motion, sitting erect.
2. BACILLINUM –
3. NATRUM MUR – Complaints from anger, grief, vexation, excessive use of salt, bread, quinine, fright, loss of vital fluid, sexual excess. Dry herpetic eruptions especially around the edges of hair, nape of neck and bends of joints. Greasy skin Worse – music, warm room, lying down, at sea shore, mental exertion, heat, talking. Better – open air, cold bathing, pressure, lying on right side, tight clothing.
4. SEPIA – Complaints from cold, laundry work, alcohol, tobacco, wetting before and during menses, after eating. Herpes circinatus in isolated spots. Itching not relieved by scratching; worse in bends of elbows and knees. Ringworm like eruption every spring.
Worse – evening, washing, left side, after sweat.
Better – exercise, pressure, warmth of bed, hot application.
5. MERCURIUS – Complaints from sugar, fright, suppressed foot sweat, suppressed gonorrhoea. Itching is worse from warmth of bed.
Persistent dryness of the skin contraindicates merc.
Worse – night, wet, damp weather, perspiration.
Better – rest, coition, weeping
6. DULCAMARA – Complaint appear at the end of the summer season when the weather becomes damp and humid. Ringworm lesions on the scalp that bleed on scratching. Eruptions on the hands, face and arms. Skin rashes in women seen just before their periods begin. Red spots and small fluid-filled boils on the skin
Worse - night, from cold or humid weather
Better - warmth.

Age - Invariably a child
Morphology
1. Discoid patch of partial alopecia from which the hair can easily and painlessly be plucked.
2. Degree of inflammation varies, depending on the strain of fungus, being more when tinea capitis is caused by zoophilic or geophilic species than with anthropophilic species.

Tinea capitis (tinea of trunk and limbs)
Morphology
Annular/arcuate lesions with relative clearing in centre and an active periphery.
Site

Infection of the glabrous skin, except palms, soles and groins.

Tinea incognito
Dermatophytic infection of skin modified by steroid therapy.
Atypical lesions, usually asymptomatic, poorly defined edge with minimal scales and papulovesicles.
Tinea cruris (tinea of groin)
Incidence - A very common condition.
Predisposing factors
⦁ Summer’s and rainy season.
⦁ Occlusion; use of synthetic clothes.
⦁ Affects men more often than women and adults more than children.
Site
Groins, genitalia, pubic area, perineal and perianal areas.
Morphology
Seen on the inner aspect of thighs as arcuate, sharply demarcated plaques with peripheral scaling, papulovesiculation, and pustulation.
Lesions expand centrifugally and centre clears.
Chronic lesions may show hyperpigmentation nodulation and Lichenification in center.
Tinea pedis
Predisposing factors
1. Hot moist weather.
2. Occlusive foot wear.
3. Hyperhidrosis of soles.
4. Sharing of wash places.
5. Presence of tinea unguium.
Morphology Three clinical patterns recognized
Interdigital variant : Interdigital scaling seen most frequently in the lateral two interdigital spaces of the feet.
Hyperkeratotic variant : well – defined scaly plaque on the sole, usually unilateral.
Hyperkeratotic variant : Well-defined scaly plaque on the sole, usually unilateral.
Vesicular variant: Recurrent vesiculation of soles.
Tinea manuum (tinea of hands )
Dermatophytic infection of the hands is usually associated with tinea pedis.
Lesions manifest as unilateral, well – defined plaques or as diffuse erythema of the palms with accumulation of fine scales in the creases.
Tinea unguium (tinea of nails)
Tinea unguium is dermatophyte infection of nails.
Incidence
Tinea of toe nails is more frequent than that of finger nails and may be associated with tinea pedis.
Tinea of finger nails is associated with dermatophytic infection of other parts of the body, e.g. tinea cruris.
Morphology
Tinea unguium usually affects only a few nails and is asymmetrical.
Nail involvement begins at the fire edge of the distal part of nail and the nail shows the following changes.
Yellow-brown discoloration and crumbling and tunneling of nail plate.
Collection of friable debris under the nail (subungual hyperkeratosis).
Separation of nail plate from nail bed (onycholysis)

ACNE VULGARIS

It is a disorder of pilosebaceous complex which predominantly affects the peripubertal population and clinically manifests as comedones (open/closed), papules, nodules, pustules and cysts and heals with scars. There is excessive secretion of sebum by which obstructing horny plugs (comedones) develop associated with inflammation of the pilosebaceous duct.

Etiology:
1. Androgenic influence - increased sebum secretion (due to increased end organ sensitivity to androgens)
2. Follicular duct hyper cornification.
3. Abnormal keratinization.
4. Infection – Anaerobic diphtheroid known as “Propionibacterium Acnes”
5. Increased colonization with Propionibacterium acnes and inflammation.

Onset: 12 - 14 years of age.
Morphology:
Polymorphic, eruption consisting of papules, pustules, nodules, cysts, and pathognomonic open and closed comedones on a background of oiliness.
Sites: Face, upper trunk, and deltoid region. Variants:
Acne conglobata, occupational acne, drug induced acne, and acne after massage.
⦁ Acne from drug and chemicals – Glucocaticoids when used for a long time as in nephrotic syndrome, rheumatoid arthritis, may produce acne.
⦁ Oil acne - Continuous use of lubricating oils, develop acne like lesion on the sites of contact. Cosmetics containing mineral oils may also produce acne.
⦁ Excoriated acne – after continuous injury of acne by nails particularly in young women, infection papules, crustification and scarification develop.
CLINICAL FEATURES
1. Skin is very much greasy due to excessive sebum secretion.
2. Comedones are seen on the hair follicles.
3. When pigmentation occurs they are called as black comedones, which are elevated papules.
4. In white comedones there is absence of keratin plugs, these can be extracted by nails.

Melasma (Greek: "a black spot") is an acquired light or dark-brown hyperpigmentation that occurs in the exposed areas, most often on the face, and results from exposure to sunlight; may be associated with pregnancy, with ingestion of contraceptive hormones, or possibly with certain medications such as diphenylhydantoin or be idiopathic. Synonyms: Chloasma (Greek: "a green spot"), mask of pregnancy.

ETIOLOGY
⦁ Hormonal factors - Estrogen often appear first during pregnancy or in a patient taking OCP.
⦁ Other factors - Sunlight plays important role, as melasma darkens after sun exposure.
⦁ Melasma has recently been appearing in menopausal women as a result of regimens for prevention of osteoporosis using a combination of oestrogens and progesterone
⦁ Melasma did not appear in those women who were given Estrogen replacement treatment but without progesterone.
⦁ Melasma is still occurring in women given the contraceptive agents that are combinations of estrogen - type compounds and progestational agents.
EPIDEMIOLOGY It is Common, especially among persons with constitutive brown skin color and who are taking contraceptive regimens and who live in sunny areas.
Age –. young adults. Peak incidence 30 - 50 years.
Race – Melasma is more apparent or more frequent in persons with brown or black constitutive skin color (people from Asia, the Middle East, India, South America).
Females are more frequently affected.
Precipitating Factors : Sun exposure plus pregnancy or oral contraceptives, diphenylhydantoin; cosmetics probably do not play a role.
Physical Examination
Skin Lesions TYPE – completely macular hyperpigmentation, the hue and intensity depending largely on the skin phototype of the patient.
Color – Light or dark brown or even black. Color is usually uniform but may be splotchy.
ARRANGEMENT - Most often symmetric
SHAPE AND BORDER OF INDIVIDUAL LESIONS - The pattern follows the areas of exposure, and the lesions have serrated, irregular, and geographic borders.
DISTRIBUTION Two-thirds on central part of the face: cheeks, forehead, nose, upper lip, and chin; a smaller percentage involve the malar or mandibular areas of the face and occasionally the dorsa of the forearms.
CLINICAL FEATURES ⦁ Brown macular pigmentation with well - defined scalloped margins.
⦁ Pigmentation darkens on sun exposure.
⦁ Symmetrically on cheeks, nose, forehead, and chin.
⦁ SEPIA – Complaints from cold, laundry work, alcohol, tobacco, wetting before and during menses, after eating. Itching not relieved by scratching; is apt to change into burning,
Worse – evening, washing, left side, after sweat.
Better – exercise, pressure, warmth of bed, hot application.
⦁ CAULOPHYLLUM – Complaints from
Worse – open air, by coffee
Better – emission of flatus
⦁ CALCAREA CARB – Complaints from defective assimilation, imperfect ossification, suppressed sweat, cold moist wind, over lifting. Unhealthy skin, readily ulcerated.
Worse – cold air, wet weather, cold water, from washing in morning.
Better – lying on painful side

Freckles are clusters of concentrated melaninized cells which are most easily visible on people with a fair complexion. Freckles do not have an increased number of the melanin-producing cells, or melanocytes, but instead have melanocytes that overproduce melanin granules (melanosomes) changing the coloration of the outer skin cells (keratinocytes).
ETIOLOGY
Inheritance - Autosomal dominant genodermatosis, seen in red haired, and fair individual.
The formation of freckles is caused by exposure to sunlight. 
Pathology - Number of melanocytes is normal, but they produce more melanosomes.
CLINICAL FEATURES
1. Lesions are multiple, ill - defined brown macules, which become darker on sun exposure.
2. Individual macule may show variegation in skin color.
3. Photo - exposed area (face, dorsolateral aspect of forearms, hands and V of neck ).

FRECKLE

1. ANT TART – Complaints from anger, vexation, smallpox, vaccination, damp, debility. Reddish itching all over the body.
Worse – damp, cold weather, lying down at night, warmth of room.
Better – cold open air, sitting upright, expectoration, lying on right side.
2 CALCAREA CARB - Complaints from defective assimilation, imperfect ossification, suppressed sweat, cold moist wind, over lifting.
Unhealthy skin, readily ulcerated, warts on face and hands. Nettle rash better on cold air.
Worse – cold air, wet weather, cold water, from washing in morning.
Better – lying on painful side.
3. LYCOPODIUM – Complaints from fright, anger, mortification, or vexation with reserved displeasure Worse – 4 – 8 p.m., right side, from heat, warm air.
Better – warm food and drinks, uncovering the head, open air.
4.SULPHUR – Complaints from alcohol, sun’s heat, suppression of skin diseases, over exertion. Dry, scaly, unhealthy skin, every little injury suppurates. Itching, burning, worse scratching and washing.
Worse – Standing, at rest, washing, warmth of bed and changeable weather.
Better – Open air, motion, lying on right side and sweating.

A corn (or clavus, plural clavi or clavuses) is a distinctively shaped callus of dead skin that usually occurs on thin or glabrous (hairless and smooth) skin surfaces, especially on the dorsal surface of toes or fingers. They can sometimes occur on the thicker skin of the palms or bottom of the feet. The scientific name for a corn is heloma (plural helomata). A hard corn is called a heloma durum, while a soft corn is called a heloma mole. Corns form when the pressure point against the skin traces an elliptical or semi-elliptical path during the rubbing motion, the center of which is at the point of pressure, gradually widening. Signs and symptom
The hard part at the center of the corn resembles a barley seed, that is like a funnel with a broad raised top and a pointed bottom. Because of their shape, corns intensify the pressure at the tip and can cause deep tissue damage and ulceration. Hard corns are especially problematic for people with insensitive skin due to damaged nerves (e.g., in people with diabetes mellitus). The location of soft corns tends to differ from that of hard corns. Hard corns occur on dry, flat surfaces of skin. Soft corns (frequently found between adjacent toes) stay moist, keeping the surrounding skin soft. The corn's center is not soft, however, but indurated.
Diagnosis
A skin biopsy.
Imaging studies to detect any underlying bony abnormalities that causes abnormal pressure on overlying skin.

CORN THERAPEUTICS

⦁ NITRIC ACID – Complaints from long lasting anxiety, overexertion of body and mind. Often useful for growth that have a horny wall surrounding a central depression .  Presence of corns with splinter-like or sticking pains.
Worse – evening, night, cold climate
Better - riding, carriage
⦁ SILICEA – Complaints from vaccination, suppressed foot sweat, exposure to draught air. Soft corns between the toes may be sore and painful. Patients may also feel burning or tearing pain in these corns. Corns between toes that tend to suppurate . Excessive sweat with an offensive odour may be present on the foot where the corn is located.
Worse – new moon, cold, during menses, from washing and uncovering.
Better –warmth, wrapping up the head and in summer.
⦁ ANTIMONIUM CRUDDUM – Complaints from disappointed love, cold bathing, alcohol, fat, fruits, suppressed eruptions, extremes of heat and cold. There is presence of large, horny corns on feet which may or may not be inflamed. Corns are very tender. Pain is felt in the corns while walking.
Worse – evening, heat, acids, water, washing
Better – open air, during rest, moist warmth.
⦁ THUJA OCCIDENTALIS – Complaints from suppressed gonorrhoea, vaccination, tea, coffee, sexual excess, sunstroke. Perspiration sweetish and strong. Dry akin with brown spots. Eruption only on covered parts; worse after scratching. Very sensitive to touch.
Worse – night, 3 p.m. and 3 a.m., from cold, damp air, cold water, fat coffee, vaccination, tobacco, touch.
Better – open air, warmth, movement, pressure, rubbing and scratching.
⦁ ARNICA – complaints from bad effect of mechanical injury, fall, blow, concussion, contusion, fright and anger. Itching, burning of the eruption. Symmetry in distribution.
Worse – least touch, motion, rest in damp cold weather.
Better – lying down

(Nettle rash, Wheals, Hives ) This is a transient localised or generalised eruption with swelling of the skin characterised by formation of wheals or hives due to endogenous or exogenous allergen.These may develop out of various immunologic or non - immunologic stimuli.
In some chronic cases autoantibodies are produced against mast cells epitopes with liberation of histamine.
Aetiology
1. Physical agents : Cold, Trauma, Stings.
2. Drugs : Liver extract, Penicillin, Serum, NSAID and various others.
3. Food : Shellfish, crabs, eggs, milk etc.
4. Parasitic inflammation by :Ascaris, giardia, lice, fleas etc.
5. Complement mediated - Serum sickness, blood transfusion reaction, necrotising vasculitis, etc.
6. Psychogenic causes
7. Idiopathic.
Types Physical urticaria
Clinical Features
The eruptions appear as raised wheals or hives surrounded by a zone or erythema.
The wheals vary in size and may blend together.
The lesions are extremely itchy.
Sometimes there may be involvement of deeper vessels resulting in swelling of the skin which is called angioneurotic edema or Giant urticaria.
This swelling may involve the mucous surface
When urticaria persists for more than 6 months its known as chronic urticaria.
The eruptions appear as raised wheals or hives surrounding a zone or erythema. The wheals by may show eosinophilia, ova, parasite or cyst together. They vary in sizes and may blend morphology varies from minutes to hours formation of various geographic bizarre are extremely patterns.
URTICARIA 1. ARSENIUM ALBUM - complaints get after midnight, in humid and rainy weather, and on consuming cold food and drinks. Excessive itching and swelling on the affected area. Dry and scaly skin eruptions, which worsen on scratching and in cold weather.
Urticaria associated with a lot of burning and restlessness.
Worse – wet weather, after midnight, from cold, seashore.
Better - heat, warm drinks and with warmth in general.
2. BOVISTA - Urticaria on excitement with rheumatic lameness, palpitations and diarrhoea. Urticaria covers nearly the whole body from exertion. Itching on getting warm, intense itching at the tip of coccyx, scratches until it bleeds, still there is no relief. Urticaria on waking up in the morning, worse from bathing.
Worse - on waking up in the morning and after bathing.
Better - after meals.
3. APIS MELLIFICA – Erysipelas, with sensitiveness and swelling, rosy hue.

1. PSORINUM – It is especially used to treat eruptions that have a foul smell. Unbearable itching.
Worse - on drinking coffee, with changes in weather, and from cold.
Better - wearing warm clothing, in summers and with warmth in general.
2. SULPHUR – Complaints from alcohol, sun’s heat, suppression of skin diseases, over exertion. Dry, scaly, unhealthy skin, every little injury suppurates. Itching, burning, worse scratching and washing. Tetters of a greenish yellow colour with itching.
Worse – Standing, at rest, washing, warmth of bed and changeable weather.
Better – Open air, motion, lying on right side and sweating.
3. NITRIC ACID – Complaints from long lasting anxiety, overexertion of body and mind.
Worse – evening, night, cold climate
Better - riding, carriage.
4. RHUS TOX – Complaints from spraining and straining, over lifting, from wetting, summer bathing in lake or river, getting wet when heated. Red, swollen, itching intense. Erysipelas vesicular eruptions, vesicles are yellow, from left to right, with much swelling,
inflammation, burning, itching and stinging erysipelatous and edematous.
Worse – during sleep, cold, wet rainy weather and after rain, during rest
Better – warmth, dry weather, motion, walking, rubbing, warm application.

1. GENETIC PREDISPOSITION - When both parents are affected by AD, >80% of their children manifest the disease. When only one parent is affected, the prevalence drops to slightly over 50%.
2. IMMUNOLOGICAL CHANGES – Patients with AD may display a variety of immunoregulatory abnormalities, including increased IgE synthesis; increased serum IgE levels; and impaired, delayed-type hypersensitivity reactions. Abnormalities of lymphocytes.

EPIDEMIOLOGY

1. Seen in 3% of all infants.
2. Begins between 3 and 6 months of age.
3. Increased exposure to pollutants.
4. Increase exposure to indoor allergens
5. Decline in breast feeling.

Type – I hypersensitivity reaction occurring as a result of the release of vasoactive substance from both mast cells and basophilis. IgE in AD shows that epidermal Langerhans cells possess high affinity IgE receptors through which an eczema – like reaction could be mediated.

The infantile phase begins after the age of 3 months. It is characterized by weeping inflammatory patches and crusted plaques on the face, neck, and extensor surfaces. Intense itchy papules and vesicles, which soon becomes exudative.
The childhood phase characterized by dry, leathery and extremely itchy plaques. Mainly on the elbow and knee flexor.
The adult phase characterized by intensely itchy, lichenified plaques. Cubital and popliteal fossae and sometimes the neck. Many of the cutaneous findings in affected patients, such as Lichenification, are secondary to rubbing and scratching.

Asymptomatic
Begins as cradle cap, usually at birth.
May involve other seborrheic area.
Self – limiting.
1. SCALP – Dandruff usually earliest and only manifestation of SD in most. Some patients develop perifollicular redness and scaling initially localized, then diffuse.
Associatedretroauricular erythema and scaling, sometimes crusted fissures develop.
2. FACE – Erythema and scaling, occur usually in association with involvement of the scalp. It may be triggered by stress and photoexposure.
Distribution – it involves medial part of eyebrows, glabella and nasolabial folds.
Association – usually associated with scalp involvement. Squamous blepharitis is common. Manifests as erythema, scaling and yellow crusts on lid margin.
3. TRUNK - Nonexudative, scaly annular and circinate lesions with follicular papules surmounted with greasy scales.
Petaloid pattern
Pityriasiform pattern.
Seborrheic folliculitis.

POINT OF DIAGNOSIS

1. Folliculocentric papules surmounted with typical yellow, greasy scales.
2. It has a typical distribution.

It is a papulosquamous disorder that may affect the skin, scalp, nails, and mucous membranes. It is flat topped inflammatory erythematous or purplish papules showing a criss – cross appearance of the surface often seen on the flexor surface of the skin with symmetric distribution along with lacy lesions of buccal mucesa. The skin lesions may occur anywhere but have a predilection for

ETIOLOGY

1. Nervous and Mental tension
2. Trauma

PATHOLOGY

At the epidermo – dermal junction band – like infiltration of melanophage, histiocyte is seen . At the same site immunoglobulin mainly IgM deposits are seen.

SITE

1. Lesions are most frequently seen on extremities and lower back.
2. Lesions may appear at the sites of trauma.
3. Lesions may appear on wrists, shins and genitalia.

1. THUJA OCCIDENTALIS – Complaints from suppressed gonorrhea, vaccination, tea, coffee, sexual excess, sunstroke.Flat black warts, large seedy, pedunculated; sometimes oozing moisture and bleeding readily. It is helpful for treating wart arising on any part of body, with a little stalk called fig – warts, tubular warts, flat warts. Dry skin, warts are sensitive to touch. Warts especially on left side of the body and on covered parts only. Unhealthy skin, offensive sweating leaves yellow stain. Patient is very sensitive to cold weather.
Worse – night, 3 p.m. and 3 a.m., from cold, damp air, cold water, fat coffee, vaccination, tobacco, touch.
Better – open air, warmth, movement, pressure, rubbing and scratching.
2. NITRIC ACID – Complaints from long lasting anxiety, overexertion of body and mind. Warts are large, jagged or pedunculated and bleed easily.
Bleeding from warts may arise from touching or washing, warts that are sensitive to touch. It also helps to treat warts that are attended with itching. There may be moist, oozing, offensive and acrid discharge from them with typical pricking splinter like pain. Often useful for growth that have a horny wall surrounding a central depression or the more common plantar wart.
Worse – evening, night, cold climate
Better - riding, carriage.
3. CARBO ANIMALIS – Complaints from loss of fluids, lifting, strain, eating spoiled fish and decayed vegetables. Warts on hand and face of old people with a bluish colour. Of extremities.
Worse – shaving, loss of animal fluid, slightest touch.
Better – laying hand on affected part.
4. NATRUM MUR – Complaints from anger, grief, vexation, excessive use of salt, bread, quinine, fright, loss of vital fluid, sexual excess. Greasy skin . Warts on palms of hands. Chaps of herpetic eruption < flexures or about knuckles.
Worse – music, warm room, lying down, at sea shore, mental exertion, heat, talking.
Better – open air, cold bathing, lying on right side.
5. PHOSPHORIC ACID – Complaints from bad news, grief, chagrin, home sickness, disappointed love, loss of vital fluid, sexual excess.
Worse – mental affections, loss of vital fluid, self-abuse, sexual excess Better – sitting, standing and warmth of bed.
6. SILICEA – Complaints from vaccination, suppressed foot sweat, draught air. Unhealthy skin. Dry finger tips. Eruption itch only during daytime and in the evening.
Worse – cold, during menses, from washing and uncovering.
Better - warmth, wrapping up the head and in summer.

It is a disorder of pilosebaceous complex which predominantly affects the peripubertal population and clinically manifests as comedones (open/closed), papules, nodules, pustules and cysts and heals with scars. There is excessive secretion of sebum by which obstructing horny plugs (comedones) develop associated with inflammation of the pilosebaceous duct.

Etiology:

1. Androgenic influence - increased sebum secretion (due to increased end organ sensitivity to androgens)
2. Oil acne - Continuous use of lubricating oils, develop acne like lesion on the sites of contact. Cosmetics containing mineral oils may also produce acne.
3. Excoriated acne – after continuous injury of acne by nails particularly in young women, infection papules, crustification and scarificationdevelop.

CLINICAL FEATURES

1. Skin is very much greasy due to excessive sebum secretion.
2. Comedones are seen on the hair follicles.
3. When pigmentation occurs they are called as black comedones, which are elevated papules.
4. In white comedones there is absence of keratin plugs, these can be extracted by nails.

1. NITRIC ACID – Complaints from long lasting anxiety, overexertion of body and mind. Often useful for growth that have a horny wall surrounding a central depression . Presence of corns with splinter-like or sticking pains.
Worse – evening, night, cold climate
Better - riding, carriage
2. SILICEA – Complaints from vaccination, suppressed foot sweat, exposure to draught air. Soft corns between the toes may be sore and painful. Patients may also feel burning or tearing pain in these corns. Corns between toes that tend to suppurate . Excessive sweat with an offensive odour may be present on the foot where the corn is located.
Worse – new moon, cold, during menses, from washing and uncovering.
Better –warmth, wrapping up the head and in summer.
3. ANTIMONIUM CRUDDUM – Complaints from disappointed love, cold bathing, alcohol, fat, fruits, suppressed eruptions, extremes of heat and cold. There is presence of large, horny corns on feet which may or may not be inflamed. Corns are very tender. Pain is felt in the corns while walking.
Worse – evening, heat, acids, water, washing
Better – open air, during rest, moist warmth.
4. THUJA OCCIDENTALIS – Complaints from suppressed gonorrhoea, vaccination, tea, coffee, sexual excess, sunstroke. Perspiration sweetish and strong. Dry akin with brown spots. Eruption only on covered parts; worse after scratching. Very sensitive to touch.
Worse – night, 3 p.m. and 3 a.m., from cold, damp air, cold water, fat coffee, vaccination, tobacco, touch.
Better – open air, warmth, movement, pressure, rubbing and scratching.
5. ARNICA – complaints from bad effect of mechanical injury, fall, blow, concussion, contusion, fright and anger. Itching, burning of the eruption. Symmetry in distribution.
Worse – least touch, motion, rest in damp cold weather.
Better – lying down.

1. Burrow - It is a serpentine tunnel made by scabies mite in stratum corneum. The open end of the tunnel has a papule.
2. Comedones – It is a tiny plug present at opening of hair follicle formed by keratin and sebum. It is of two types: Open comedone (black head) and Closed comedone (white head).
3. Milia – It is a tiny superficial cyst with epidermal lining. Milia are seen on face at periorbital. They are small, firm, white papules filled with keratin.
4. Telengiectasia – It is visible dilatation of capillaries of skin which blanch on pressure.
5. Poikiloderma – It is a combination of reticulate telangiectasia, pigmentary change and atrophy.
6. Purpura – Extravasation of red blood cells from cutaneous vessels in skin and mucous membrane.
7. Infarct – Area of cutaneous necrosis – tender, irregularly shaped dusky red grey macule or firm plague.