Dermatology Exam Flashcards
8 Steps in The Skin Exam:
- Preparation - pt gowned, lighting adequate
- Examination - carefully examine entire skin surface
- Palpate - palpate lesions to determine elevation
- Texture - Determine texture of lesions
- Scale - Scalpel blade used to check for scale; can be examined microscopically if fungal infection is suspected
- Size - measure/record measurements of lesions
- Diascopy - Differentiate between blanching erythema and non-blanching purpura by pressing with a glass slide
Flat lesions:
Macule, Patch
Smooth, raised lesions:
Cyst, Nodule, Papule, Plaque
Surface change lesions:
Crust, Scale
Fluid-filled lesions:
Bullae, Pustule, Vesicle
Red blanchable lesions:
Erythema, Erythroderma, Telangiectasia
Purpuric lesions:
Ecchymosis, Petechiae, Palpable Purpura
Sunken lesions:
Atrophy, Erosion, Ulcer
Necrotic lesions:
Eschar, Gangrene
Ddx for lesions on the head:
Syringoma: tiny bumps around lower eyes
Alopecia areata: balding
Dermatomyositis: Erythema on upper eyelid
Herpes simplex virus: cold sores on mouth
Ddx for lesions on the neck:
Cutis rhomboidalis nuchae - “quilt-looking” neck
Acne keloidalis nuchae - acne at base of skull/upper neck
Poikiloderma of civatte - red/brown rash on anteromedial neck
Acanthosis nigricans - Dark, velvety patches in the folds of the neck.
Ddx for lesions on the chest:
Steroid acne - pimples diffusely covering the chest
Nipple dermatitis - scaly, erythematous nipple
Darier’s disease - erythematous crusting of the chest
Drug-induced photosensitive reaction - diffuse erythema across the sternum
Ddx for lesions on the abdomen:
Morphea - red plaque scattered across the abdomen
Striae - stretch marks
Pityriasis rosea - diffuse pustules across the abdomen (usually starts with one large lesion)
Atopic dermatitis - eczema
Ddx for lesions on the arms:
Lichen planus - autoimmune disease where skin immune system attacks skin/ mucous membranes and creates purple, itchy, flat-topped bumps.
Keratosis pilaris - small acne-like bumps on the skin
Actinic keratosis - rough scaly patch, caused by sun exposure
Prurigo nodularis - Large, itchy, symmetrically distributed lesions that cause pain and discomfort
Ddx for anogenital lesions:
Condyloma acuminatum - genital warts (HPV)
Lichen sclerosus et atrophicus - thin, white patches of skin in genital area
Herpes simplex virus - pustulous lesions on genitals
Tinea cruris - fungal infection (jock itch)
Ddx for hand lesions:
Psoriasis - severely peeling fingernails
Scabies - Contagious, caused by burrowing skin mite
Secondary syphilis - rash on palms/soles
Dyshidrotic dermatitis - tiny, fluid-filled blisters on palms/fingers
Ddx for leg lesions:
Henoch-Schonlein Purpura (HSP) - diffuse petechiae; usually seen in children < 7
Livedo reticularis - Purple, net-like pattern of skin discoloration on the legs
Erythema induratum - nodular vasculitis (tuberculid skin erruption)
Stasis dermatitis - skin inflammation caused by fluid build up
Ddx for foot lesions:
Cutaneous larva migrans - parasitic “hookworm” infection; red, twisting lesions
Tinea pedis - “athlete’s foot” fungal infection
Plantar wart
Pitted keratolysis - patchy erosion of the bottom of the foot
Define acral distribution of skin lesions:
Involves the distal aspects of the head (ears, nose) and the extremities (hands, fingers, feet, toes).
Define dermatomal distribution of skin lesions:
Involves the area of skin supplied with sensory innervation by a particular nerve root. These do not cross the midline of the body.
Define intertriginous distribution of skin lesions:
Involves skin creases and folds. Includes involvement of the axillae, crural fold, gluteal crease, and possibly the inframammary fold.
Define lymphangitic distribution of skin lesions:
Appears along the path of lymph channels of the leg or arm.
Define photodistributed distribution of skin lesions:
Follows sun-exposed skin. Areas of involvement include forehead, upper ears, nose, cheeks, upper lip, neck, forearms, and dorsum of the hands.
Define scattered distribution of skin lesions:
Skin lesions occurring across many body locations; can appear to be distributed randomly or haphazardly.
Define symmetric distribution of skin lesions:
Skin lesions found symmetrically on the extremities can be indicative of diagnoses with many etiologies, including infectious, metabolic, genetic, and inflammatory causes.
Define widespread distribution of skin lesions:
Involves entire, or almost entire, body.
What shape is an annular lesion?
Ring-shaped
What shape is an arcuate lesion?
Arc-shaped
What shape is an grouped lesion?
Clustered
What shape is an linear lesion?
Straight line
What shape is an polycyclic lesion?
Coalescing circles, rings, or incomplete rings
What shape is an reticular lesion?
Net-like
What shape is an scattered lesion?
Irregularly distributed
What shape is an serpiginous lesion?
Snake-like, or serpent-like in shape
What shape is an targetoid lesion?
Shaped like a target
What shape is an whorled lesion?
Stirred appearance
What is eczematous dermatitis?
Most common inflammatory skin d/o; several forms: contact dermatitis, allergic contact dermatitis, atopic dermatitis
What is folliculitis?
Inflammation/infection of the hair follicle and the surrounding dermis
What is a furuncle (boil)?
A deep-seated infection of a pilosebaceous unit. Usually caused by staphylococcus aureus.
What is cellulitis?
Diffuse, acute infection of the the skin and subcutaneous tissue. Majority of cases caused by Streptococcus pyrogens or Staphylococcus aureus.
What is tinea (dermatophytosis)?
Group of non-candidal fungal infections that involves the stratum corneum, nails, or hair.
What is pityriasis rosea?
Self-limiting inflammation of unknown cause. Non-contagious; often occurs in adults during spring time.
What is psoriasis?
Chronic, recurrent disease of keratinocyte proliferation. Multifactorial origin with a genetic component and immune regulation.
What is rosacea?
Chronic inflammatory skin d/o. Most often occurs in fair-skinned persons.
What is herpes zoster (shingles)?
Varicella-zoster viral (VZV) infection; dormant viral particles from varicella infection in the posterior spinal ganglia or cranial sensory ganglia become activated and spread along the nerves.
What is herpes simplex?
Infection by HSV; type 1 - oral infection; type 2 - genital infection. Crossover infections have become common.
What is lyme disease?
Tick-borne disease that can result in a multisystemic infection. 3 stages: early localized, early disseminated, and late disease.
What are drug eruptions?
Cutaneous reactions to medications. Rash usually accompanied by pruritis.
What is acanthosis nigricans (AN)?
Non-specific reaction pattern associated with obesity, certain endocrine syndromes, or malignancies, or as an inherited d/o.
What is basal cell carcinoma?
Most common form of skin cancer that arises from the basal layer of the epidermis. Occurs most frequently on exposed parts of the body.
What is squamous cell carcinoma?
Second most common form of skin cancer. Malignant, arises in the squamous epithelium, and occurs most commonly in sun-exposed areas.
What is a malignant melanoma?
Lethal form of skin cancer that develops from melanocytes. Exact cause is unknown.
What is a Kaposi sarcoma (KS)?
A neoplasm of the endothelium and epithelial layer of the skin. Caused by Kaposi sarcoma herpes virus 8; commonly associated with HIV.
What is alopecia areata?
Sudden, rapid coin-shaped loss of hair, usually from the scalp or face. Any hair-bearing surface may be affected. Regrowth may begin in 1-3 months.
What is scarring alopecia?
Replacement of hair follicles with scar tissue; results in permanent hair loss.
What is traction alopecia?
Hair loss as a result of prolonged, tightly pulled hairstyles. Follicle is undamaged and hair loss is reversible.
What is hirstuism?
Growth of terminal hair in women in the male distribution pattern on the face, body, and pubic areas.
What is paronychia?
Inflammation of the paronychium; caused by invasion of bacteria/yeast between the nail fold and nail plate.
What is onychomycosis?
Fungal infection of the nail.
What are ingrown nails?
Nails that pierce the lateral nail fold and grow into the dermis.
What is a subungual hematoma?
Trauma to the nail plate severe enough to cause immediate bleeding and pain (bruised fingernail)
What is onycholysis?
Loosening of the nail plate with separation from the nail bed that begins at the distal groove.
What is koilonychia?
Spoon nails; central depression of the nail with lateral elevation of the nail plate. Associated with iron deficiency anemia, syphilis, fungal dermatoses, and hypothyroidism.
What are beau lines?
Transverse depressions in the nail beds; due to systemic d/o’s.
What is white banding (Terry nails)?
Whitening of the proximal half to three-quarters of the nail bed. Associated with cirrhosis, chronic CHF, adult-onset DM, and age.
What is psoriasis (nails)?
Chronic, recurrent disease of keratinocyte proliferation. Nail involvement usually occurs simultaneously with skin disease.
What are warts?
Epidermal neoplasms caused by viral infection (HPV).
What are digital mucous cysts?
Cyst-like structures at the base of nails that contain a jelly-like substance. Not connected to the joint space of the DIP.
What is a polymorphic eruption of pregnancy?
Benign dermatosis that usually arises late in the third trimester of pregnancy. Pruritic rash that usually starts on the abdomen and spreads (periumbilical area is spared).
What is seborrheic dermatitis?
Chronic, recurrent, erythematous scaling eruption localized in areas where sebaceous glands are concentrated.
What is Millaria rubra “prickly heat”?
Caused by sweat retention from occlusion of sweat ducts during periods of heat/high humidity.
What is impetigo?
Common, contagious, superficial skin infection. Lesion, typically on the face, that itches and burns. Vesicle/bulla that turns into a crust as it heals.
What is acne vulgaris?
Most commonly reported in adolescents; scarring may be present from previous lesions.
What is chickenpox (varicella)?
Acute, highly communicable disease common in children and young adults; caused by VZV. Pruritic rash that started on scalp and moved to extremities; sxs fever, HA, sore throat, and malaise. Vaccine available
What is measles (rubeola)?
Measles virus infects by invasion of respiratory epithelium; both endothelial and epithelial cells are affected. Sxs: fever, conjunctivitis, stuffy nose, cough, followed by red, blotchy rash starting on face and spreading to the trunk/extremities. Vaccine available
What is German measles (Rubella)?
Mild, febrile, highly communicable viral disease. Macular rash on the face/trunk that spreads and becomes papular. Spread through respiratory droplets.
What is tricholtillomania?
Hair-pulling leading to loss of scalp hair; unconscious habit.
Signs of physical abuse in kids:
Bruises Lacerations Burns Hair loss Presence of anogenital warts in kids < 2 years
What s stasis dermatitis?
Swelling and erythema of the extremities due to fluid build up within the tissues. Occurs in the LEs of patients with venous insufficiencies.
What is actinic keratosis?
Atypical squamous cells confined to the epidermis; occurs secondary to chronic sun damage. Lesions may evolve into squamous cell carcinoma over time.
