Dermatological History and Examination age, sex Chief complaint : + duration itching burning pain History of present illness When and how started? Mild, moderate or severe? Aggravating or reliving factors? Any other symptoms Review of systems Past medical history Drug history

Occupation Hobbies Travel Family history

Examination: 3 corners to make useful skin exam Morphology (shape of the lesion) Configuration (arrangement of lesions) Distribution (Which body site) Morphology: 1º skin lesions : unmodified lesions 2º skin lesion: modified by scratching or infection

Primary Lesions Secondary lesions Macule Crust Papule Erosion Plaque Scale Nodule Ulceration Cyst Excoriation Wheal Scar Vesicle Atrophy Bulla Fissure Purpura Necrosis Burrow Lichenification Telangectasia

Primary skin lesions

Macule & patch A macule is a circumscribed flat alteration in the colour of the skin which is less than 1 cm in diameter. Various colors depending on the cause A patch is a flat lesion greater than 1 cm in diameter (i.e. a large macule).

Papule A papule is a circumscribed palpable elevation of the skin less than 1 cm in diameter Dermal(drug eruption, lipid deposits), epidermal (warts, molluscum), or both (lichen planus)

Nodule Palpable solid deep lesion (depth> diameter) - Epidermal

Plaque A slightly raised lesion greater than 1 cm in diameter Papules confluence (psoriasis) Patch thickening (mycosis fungoides)

Vesicle A raised lesion less than 0.5 cm in diameter containing clear fluid

Bulla A vesicle that is greater than 0.5 cm in diameter is known as a bulla.

Pustule A pustule is a raised lesion less than 0.5 cm in diameter containing yellow fluid, which may be sterile as in acne or pustular psoriasis, or infected.

Wheal A wheal is a transient, itchy, pink or red swelling of the skin, often with central pallor.

Cyst: palpable soft sac containing fluid. - Epidermal - Dermal

Telangiectasia Dilatation of capillaries gives rise to this skin condition.

Secondary skin lesions

Crust A crust is a dried exudate, which may have been serous, purulent or haemorrhagic.

Excoriation A haemorrhagic excavation of the skin resulting from scratching.

Lichenification Thickening of the skin with exaggeration of the skin creases.

Scar The final stage of healing of a destructive process (disease or injury) that has involved the deeper dermis results in a white, smooth, firm, shiny lesion. Atrophic, or hypertrophic

Scale A scale is a flat plate (lamella) or flake of stratum corneum. The epidermis is replaced in cycles Fine (eczema) / thick (psoriasis) No scaling in dermal pathologies

Poikiloderma This refers to an appearance of pigmentation, atrophy and telangiectasia

Necrosis Death, or necrosis, of skin tissue is usually black in colour.

Erosion A partial break in the epidermis is known as an erosion It heals without scarring unless secondary infection occurs. Commonly following a blister

Ulcer An ulcer is a full-thickness loss of the epidermis Heals with scarring

FISSURE a linear cleavages or cracks in the skin.

Atrophy Thinning and transparency of the skin Caused by diminution of the epidermis, the dermis, or both Wrinkling and translucency

Primary Lesions Macule: Flat circumscribed area of change in skin color Papule: small circumscribed elevation of the skin Nodule:Solid, circumscribed elevation of the skin whose greater part is beneath skin surface (felt more than seen) Plaque: flat topped palpable lesion (gathering of papules) Vesicle: collection of clear fluid (<5mm in diameter) Bulla: like vesicle, but > 5 mm Pustule: Collection of Pus

Primary Lesions * Wheal: Transient, slightly raised lesion with pale center and pink margin.Seen in urticaria. * Purpura:Visible collection of blood under the skin e.g. Vasculitis * Telangectasia: Dilated capillaries visible on skin surface * Burrow: Tunnel in the skin (e.g. Scabies)

Secondary lesions Crust: Dried serum (or exudate) Scale:Thickened, loose, readily detached fragment of cornified layer Excoration: Shallow linear abrasion caused by scratching. Erosion:Loss of epidermis (heals without scarring) Ulcer: loss of epidermis and dermis (heals with scarring) Fissure : linear crack in the skin Scar: Permanent lesion due to abnormal formation of connective tissue following injury.

Secondary lesions Atrophy: A-Superficial: thining of skin with visible blood vessels B-Deep : depression of skin surface Lichenification: thickened skin with accentuated skin markings Sclerosis: induration of skin

Distribution Predilection for specific body sites *Psoriasis: Extensors(elbows and knees) Scalp *Acne:Face Upper chest, Upper back *Photosensitive eruption: Mainly face, forearms & V-Chest (with sparing of photoprotected areas e.g. upper eyelids, retro-auricular an sub- mental)

Colour in Dermatology Red:Vascular lesions e.g. port wine stain also, inflammatory disorders like psoriasis Blue: Blue nevus Mongolian spot Yellow: Xanthoma White: Vitiligo Black: Melanocytic nevus & melanoma Purple or (Violaceous) : Lichen planus

Some important signs in Dermatology *Auspitz sign: When you remove a scale from psoriasis lesion  tiny bleeding points (due to suprapapillary thinning). Nikolsky sign: When you rub normal skin beside blister  induction of new blister .Seen in pemphigus vulgaris and toxic epidermal necrolysis(TEN).

Nikolsky sign

Dermatographism: When you stroke the normal skin  edema and erythema (you can write on skin!) .Seen in physical urticaria Kobener Phenomenon: Induction of new skin lesions on previously normal appearing skin by truma e.g. in psoriasis, wart, lichen planus Button-hole sign: In neurofirbroma, if you try to push it  it goes inside the skin

Kobener Phenomenon

Dermatographism

Additional skin examination: ~Wood’s Lamp: Produces long wave ultraviolet light(UVA). e.g. Vitiligo  milky white Tinea Versicolor  golden Tinea Capitis (caused by microsporum)  yellow green Erytherasma  coral red ~Diascopy:you press with a glass slide . If there is red lesion and the redness dose not go away by this pressure  this means extravasated blood i.e.purpura ~Dermatoscopy: Helpful to differentiate benign from malignant pigmented lesions.

Diascopy

Investigations: *KOH and fungal culture Scrap skin scales  put over glass slide Add KOH 10% -- warm gently See under microscope You may see hyphae and/ or spores *Gram stain and bacterial culture

Investigations: Tzank smear: Scrap base of vesicle smear it on microscopic slide  add fixative  add Giemsa stain. Examine under microscope for 1.Detached epidermal cells (acantholytic cells) in pemphigus vulgaris 2.Multinucleated giant cells in herpes simplex, zoster or varicella Viral culture

important in immunobullous disorder 1. Direct : use pt’s skin Skin biopsy : Under local anasthesia, different types: Punch Shave Excisional Incisional Immunofloursence : important in immunobullous disorder 1. Direct : use pt’s skin 2. Indirect: use pt’s Serum

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