Topic 17. Primary Lesions of the Skin

Dermatologic Diagnosis Examination of the patient A dermatological dg. is based on both lesions distribution and on their morph. and configuration. For ex. → an area of seborrhoeic dermatitis may look very like an area of atopic dermatitis so the key to dg. lies in the location:  Seborrhoeic dermatitis → affects scalp, forehead, eyebrows, nasolabial folds and central chest  Atopic dermatitis → typically affects the antecubital and popliteal fossae. Components of the Dermatologic Evaluation 1) Patient age and history → history taking should include:  Time line - where and when the problems started  Symptoms (severe itch, mild itch, pain)  General medical history  Medication and allergies  Occupation and recreation, travel  Family and household contacts  The patient’s own view in the likely cause Time line How long have any lesions been present? Have they changed in time? Patients will tell you how long they have had the lesion which is CURRENTLY worrying them and will not begin at the beginning of their problem. Where did the problem first appear? Does it appear or spread to other body parts? Patients will show you a lesion on a visible part of their body, and will not tell you about large lesion at for ex. their back → ask for ALL lesions and their localization. Symptoms → there are 7 most important questions to evaluate symptoms: 1. Localization - Where is it? 2. Quality - What is it like? 3. Quantity or Severity - How bad is it? 4. Timing - When did it start? How long does it last? How often does it come? 5. The setting in which it occurs, including environmental factors, personal activities, emotional reactions, or other circumstances that may have contributed to the illness. 6. Factors that make it better or worse. 7. Associated manifestations. In dermatology, the symptoms are usually itch and/or pain.  Severe itch → associated with conditions such as scabies, atopic eczema, contact dermatitis, dermatitis herpetiformis.  Mild itch → associated with many conditions such as psoriasis, drug eruptions, bullous pemphigoid  Pain → is a symptom of vasculitis and pemphigus.

General medical history There are many skin signs which may be the first marker of an internal disease (for ex. DM) → ask about underlying diseases, family history, previous hospitalizations, allergies. Occupational and recreational history  Ask the patient about his environment (including contact with animals).  May be particularly important in conditions such as contact dermatitis.  Ask about reaction to sunlight exposure → Lupus erythematosus, for ex. is aggravated by sunlight. Travel → For example, South America visit 6 weeks ago may explain the crusted sore on the wrist (localized form of leishmaniasis). Family and household history Ask about first degree relatives and houshold contact (do not have to be family members). Infections such as scabies may infect both relatives, and other contacts. 2) Examination of the skin 1. Characteristics (primary, secondary) → later 2. Location of lesion 3. Description of the lesion 4. Distribution (groups, disseminated) and Pattern Do not forget to check the nails, hair, and mucous mem!!! Location of lesions Frequent association b/w common skin diseases and body site  Scalp - psoriasis, seborrhoeic dermatitis, fungal infec.  Face - Atopic dermatitis, acne, rosacea, seborrhoeic dermatitis, lupus erythematosus, and other photosensitive problems  Body flexures - seborrhoeic dermatitis, psoriasis, fungal infec., candida infections  Feet - toe webs (fungal infec.), soles (juvenile plantar dermatosis), dorsa (contact dermatitis) Disease Acne vulgaris Atopic dermatitis Herpes zoster Light-sensitive eruption Pityriasis rosea Psoriasis Seborrhoeic dermatitis Common site face and upper part of back flexor sites of limbs vesicles in a unilateral dermatoma light exposed areas trunk, upper parts of limbs extensor sites of limbs face, head, neck

Description of the lesion 1. Color → salmon-pink, lilac, violet 2. Nature → uniform, irregular, patchy... 3. Form: Configuration, border, and surface  Annular = circular or ring-shaped.  Arcuate = curved.  Circinate = arched or rounded border.  Discoid, nummular = disk or coin-shaped.  Gyrate = wave-like.  Iris or cockade = target-like  Serpiginous = winding, twisting (snake-like). 4. Border → Sharp (well-circumscribed) or vague (blurred). 5. Surface→ Smooth, rough, warty, vegetating, glistening, dull, dome-shaped, umbilicated... 6. Consistency → Soft, doughy, hard, fluctuant, lobed, knotty, moveable, fixed, attached to … 7. Smell → foul-smelling 8. Temperature → hot, warm Distribution and patterns  Linear: Following a line.  Lines of Blaschko: Following embryologic skin lines  Retiform and reticulate: net-like.  Grouped  Herpetiform: Arranged in clusters, grape-like.  Zosteriform: Following a dermatome  Discrete: Solitary.  Confluent: Blending together.  Chessboard pattern: Arranged in rectangular patterns.  Disseminated: Randomly distributed. Distribution over skin surface  Degree of spread: Localized, regional, generalized (widespread), universal.  Limited to certain areas (such as palms and soles or scalp).  Specific patterns: Symmetrical, asymmetrical, light-exposed skin, lightprotected skin, intertriginous areas, seborrheic areas, pressure points, sites of predilection. Relation to skin appendages Each lesion centered about a hair, producing a distinctive pattern.  Interfollicular → Not involving hairs.  Palmoplantar → Limited to palms and soles, thus not connected with hairs.  Favoring regions with large concentrations of sebaceous glands or sweat glands.

Description of complex findings The following terms are frequently used in dermatologic descriptions but are not traditionally considered primary or secondary lesions.  Atrophy: Loss of skin substance.  Angioedema is a diffuse swelling caused by edema extending to the subcutaneous tissue.  Ecchymosis: Large area of extravasation of erythrocytes.  Enanthem: Abrupt appearance of mucosal lesions, similar to exanthem.  Erythema: Redness of the skin  Erythroderma: Diffuse redness of the entire skin, usually associating with scaling.  Exanthem: Abrupt appearance of diffuse or generalized similar skin lesions (usually represents viral infection or drug reaction).  Lichenification: Response of skin to chr. rubbing, leading to thickening with accentuated markings.  Livedo: Blue-red discolour. of skin due to passive congestion of vessels, often with net-like pattern.  Papilloma is a nipple-like projection from the skin.  Petechiae: Tiny areas of extravasation of blood, usually pinhead-size.  Poikiloderma: Combination of telangiectases, atrophy and reticulate hyperpigmentation  Rhagade or fissure: Linear split or defect, extending into dermis and often originating from an orifice.  Purpura: a larger macule or papule of blood in the skin. Such blood-filled lesions do not blanch if a glass lens is pushed against them (diascopy).  Sclerosis: Hardening and thickening of skin, so that it is less freely moveable, often associated with contraction so that involved area lies below level of normal skin.  Sinus: Tract lined with epithelium, often discharging secretions.  Suggillation: Synonym for ecchymosis, also used for bruise or contusion.  Comedo is a plug of greasy keratin wedged in a dilated pilosebaceous orifice. - Open comedones → black-heads. - Closed comedo → the follicle opening is covered by skin so it looks like a pinhead-sized, ivory-coloured papule.  Burrow is a linear or curvilinear papule, with some scaling, caused by a scabies mite.  Telangiectases: visible, irreversible dilatation of small cutaneous blood vessels Description of General Skin Condition, Vascular Status, and associated findings  General terms: Xerotic (dry), seborrheic (oily), ichthyotic (scaly), actinic damage, atrophic, thickened, abnormal texture, hyper-, hypo- or anhidrotic.  Vascular status: Cyanotic, pale, cold, warm, edematous, with varicosities, necrotic.  Nature of wound healing: - Central or peripheral healing, with scarring or atrophy. - Pigmentary changes, erosion or ulcer, crust, or scale.  Dynamics of lesion: All lesions in same stage or lesions in different stages.  Associated findings: Lymphadenopathy, fever, malaise, as examples.

Topic 17 - Primary lesions of the skin Skin lesions can be classified into Primary or Secondary In differentiating 10 and 20 lesions, 20 lesions typically follow 10 lesions but are less characteristic, therefore, dermatologic classification begins with search for primary lesions. Primary lesions are the basic elements of skin morphology, they can undergo a variety of changes to become secondary lesions  First signs of the skin disease.  As a physician you usually see the 20 lesion on the patient → must ask what the lesion first looked.  Characteristics of the lesion, lesion size and the relationship to skin MUST be described. Types of primary lesions 1) Macule / patch 2) Infiltrative primary skin lesions → papule/plaque, tuber, nodule/node 3) Exsudative primary skin lesions → urtica/wheal, vesicle/bulla, pustule Macule / patch Circumscribed, flat, NOT palpable discoloration of the skin  Macule < 0.5 cm in size.  Patch > 0.5 cm The skin pigmentation can be classified as  Endogenous pigment → hemoglobin, melanin ↑ or ↓  Exogenous pigment  Vascular origin Possible colors and their common causes  Red: Hyperemia (erythema) - Telangiectases - Leakage of blood (Purpura, Petechia, Ecchymosis, suggillation (bruise))  Blue: Cyanosis, hematoma (black eye), dermal melanin  Brown: Dermal and epidermal melanin, hemosiderin  White: Anemia, vasoconstriction, loss of melanin  Yellow: Carotenoids, bile, solar elastosis (Premature aging of the skin)  Gray-black: Epidermal melanin, heavy metals, tar, dithranol, foreign Bodies

Vitiligo

Associated pathologies and examples 1. Ephelis (freckles) → hyper-pigmentation. For ex. Puetz-Jeger sy. Peutz-Jeghers sy.  AD inherited disorder→ serine/threonine protein kinase 11 (STK11) gene mutation  characterized by intestinal hamartomatous polyps in association with a distinct pattern of skin and mucosal macular melanin deposition. 2. Porphyria cutanea tarda (PCT) Metabolic disease involving hyper- or hypo-pigmentation that occur on sun exposed skin.. 3. Fixed drug eruption → a hyperpigmented macule (or a bullous plaques)  Round, erythematous or purple, recur at the same site each time the drug is taken.  may occur after taking salicylic acid 4. Vitiligo → hypo-pigmentation of the skin due to dysfunction of melanocytes. An autoimm. disease usually due to auto reactive T cells → killing melanocytes. 5. Halo/Sutton nevus → pigmented nevus surrounded by a hypopigmented macular border (white spot). Sometimes it can disappear. 6. Incontinentia pigmenti– Rare x-linked inherited hypopigmentation disorder, seen in babies. 7. Purpura → bleeding into the skin.  Palpable Purpura→ not a macule, it is a sign of supf. vasculitis (type III HS reaction) 8. Exogenous pigment tattoo → considered to be a macule. 9. Erythema e calore → hyperpigmentated erythema. If you feel the skin and it is a bit more firm, there is probably an ↑cellular content in the lesion and it is not a macule. Infiltrative primary skin lesions – all have cellular infiltration 1) Papule/plaque  Papule → small solid elevation of the skin <0.5 cm. caused by ↑ thickness in epidermis, dermis, or both (Intradermal and/or epidermal papule). The colour may vary  Plaque → elevated area of skin > 0.5 cm diameter but w/o substantial depth. - They have infiltrated T ly-s. - Papules may become confluent and form plaques - Associated pathologies: Lichen planus, Psoriasis (papule/plaque), Erythema multiforme 2) Tuber - cellular infiltration involving the entire depth of the dermis. 3) Nodule/node - circumscribed, elevated cellular infilt. in the dermis and subcutis Plaques (psoriasis)  often round, solid lesion > 0.5 cm in diameter.  A large nodule (>1cm) is referred to as a tumour (BCC, Lipoma, Wart, Furuncle) Tumors may courteously be called ‘large nodules’, especially if benign.

Papule

Exsudative primary skin lesions (collection of fluid) 1) Wheals/urtica (hive)  Transient papule or plaque caused by dermal edema  Wheal is an elevated white compressible evanescent area.  It is often surrounded by a red axon-mediated flare.  Usually < 2 cm. May last several hours 2) Vesicle, bulla  intraepidermal  acantholytic  subepidermal Vesicle → small (up to 0.5 cm in diameter) circumscribed collection of fluid in the epidermis or below the basal layer Result of vesicles: oozing, crusts, scaling. Bulla → Larger collection of fluid (> 0.5 cm). can be intraepidermal or subepidermal. 3) Pustule A circumscribed, supf. cavity of the skin that contains pus in or below the epidermis  Primary pustules (sterile) → pustular psoriasis  Secondary (pyogenic infec.) → impetigo
Vesicle

Lesions characteristic for pathological conditions Macules  Infec. exanthemas → measles, rubella, scarlet fever  Drug eruptions               Lichen planus Lichen simplex chronicus (localized neurodermatitis) Metabolic disorders (deposition of uric acid...) Prurigo Epizoonosis Lymphocytoma, lymphomas Drug eruptions Atopic dermatitis Bact. → 20 syphilis, TB, leprosy Leishmaniasis Sarcoidosis Rosacea Warts Molluscum contagiosum

Papules

Nodules

     

Deeper vasculitis (erythema nodosum, nodular vasculitis) Gumma (30 syphilis), leprosy Leishmaniasis Sarcoidosis, granuloma annulare Tophus Tumors, lymphomas

Vesicles

 Virus vesicles (zoster, herpes simplex, varicella)  Contact dermatitis, mostly allergies  Recurrence and spread of eczematous lesions by absorption of allergens (percutaneous, oral ...)  Dermatitis herpetiformis (Duhring’s disease)  Fungal disease, epizoonosis  Miliaria         Acne and acne-like conditions (drug-induced acne) Mercury dermatitis Pustular psoriasis Persistent palmoplantar pustolosis Reiter’s disease Epizoonoses Fungal infections Pyodermas (folliculitis barbea)

Pustules