Dermatology Flashcards
Flat discolored lesion
Less than 1 cm = macule
Greater than 1 cm = patch
Palpable raised lesion
Less than 1 cm = papule
Greater than 1 cm = plaque
Lesion with significant depth
Less than 1 cm = nodule
Greater than 1 cm = tumor
Fluid containing lesion
Greater than 1 cm = cyst
Elevated lesion containing serous fluid
Less than 1 cm = vesiscle
Greater than 1 cm = bullae
What causes Rocky Mountain spotted fever?
Rickettsia rickettsii tick bite
Sudden onset fever, headache, rash, myalgia, GI complaints
Common phototoxic drugs
NSAIDs, quinolones, tetracyclines, amiodarone, phenothiazine
Dermatomyositis lesions
Violaceous periorbital HELOPTROPE RASH with edema
Erythema of neck and upper trunk SHAWL SIGN
Violaceous papules over knucles GOTTRON PAPULES
Treatment for tinea versicolor (overgrowth of M furfur)
Selenium sulfide lotion
Oral ketoconazole
Define vitiligo
Autoimmune reaction against melanocytes associated with other autoimmune diseases such as pernicious anemia, Hashimoto’s thyroiditis or diabetes type 1
Itchy red macules and papules on the face spreading to the neck, trunk and extremities within 24 hours ± red rash on soft palate
Rubella
Post auricular lymph nodes
Resp spread
Careful in pregnant ladies
Small white spots on oral mucosa with erythematous macules and papules of face spreading cephalocaudally
Measles
Pink macules and papules on trunk spreading to neck and proximal extremities with surrounding white halos
Roseola
Skin changes in liver disease
Gynecomastia, jaundice, caput medua, loss of body hair, palmar erythema, peripheral edema, purpura, spider angioma
Skin changes in renal failure
Photodistributed or diffuse hyperpigmentation including palms and soles, pallor, yellow tinge
Skin changes in diabetes
Acanthosis nigricans, foot ulcers, itching, light brown slightly indented scaly patches (diabetic dermopathy), yellow skin and nails
Skin changes in Cushing syndrome
Acanthosis nigricans, acne, buffalo hump, hirsutism, telangiectasia, atrophic skin, striae
Skin changes in neurofibromatosis
Cafe au lair spots, freckles, neurofibromas
Skin changes in hyperlipidemia
Xanthomas
Finger clubbing should make you think of
CVD
Lung disease
GI disorders
Chronic methemoglobinemia
Hollow or spoon shaped nails should make you think of
Iron deficiency
Malnutrition
Diabetes
Old age
Transverse white lines/leukonychia should make you think of
Hypoalbuminemia
Chemotherapeutic agents
Poisons
Black spots on nails should make you consider
Hematoma or melanoma
Splinter hemorrhages of nails should make you think of
Trauma
Bacterial endocarditis
Blood dyscrasia
Blue green nails should make you think of
Pseudomonas or drug induced causes (azidothymidine AZT)
Painful grouped vesicles on erythematous base located on distal finger
Herpetic whitlow
Self limiting
May consider antiviral therapy
MCC noncicatricial (without scarring) alopecia
Androgenic alopecia
Skin changes in liver disease
Gynecomastia, jaundice, caput medusa, loss of body hair, palmar erythema, peripheral edema, purpura, spider angiomas
Skin changes in renal failure
Photodistributed or diffuse hyperpigmentation including palms and soles, pallor, yellow tinge
Skin changes in diabetes
Acanthosis nigricans, foot ulcers, pruritis, light brown slightly indented scaly patches, yellow skin and nails
What is pyoderma gangrenosum and what conditions is it associated with?
Inflammatory skin condition that is characterized by large ulcers usually on the lower body
Associated with ulcerative colitis, Crohn’s, rheumatoid arthritis
Skin changes in neurofibromatosis
Cafe au lait macules, freckles, multiple cutaneous neurofibromas (neoplasm of peripheral Schwann cells that presents as soft nodule in the dermis of the skin)
Skin changes in porphyria
Blisters, photosensitivity, hypertrichosis, pigmentation, skin fragility
Porphyrias are a group of rare, inherited or (less commonly) acquired metabolic disorders in which defective enzymes impair the biosynthesis of heme in the liver and/or bone marrow.
Treatment for onychocryptosis
aka ingrown nails
Barrier placement between nail plate and fold
Excision of the portion of the nail plate pressing on the fold
Maybe antibiotics
What is fingernail clubbing associated with?
CVD, lung disease, GI disorders, chronic methemoglobinemia
What are spoon shaped nails associated with?
Iron deficiency, malnutrition, diabetes, old age
What are white lines on nails associated with?
Hypoalbuminemia, chemotherapy, poisons
What are nail splinter hemorrhages associated with?
Trauma (MCC)
Bacterial endocarditis, blood dyscrasias
What are black nails associated with?
Hematoma, melanoma
Always biopsy when melanoma is suspected
Where does herpetic whitlow normally present?
Erythematous base located on the distal finger
What are red painful lesions around the nail fold called and what are they commonly caused by?
Paronychia
Causes: MCC S. aureus if acute, if in someone who does “wet” work then think C. albicans
Rx: Topical glucocorticoids, minimize irritants and water exposure, give topical antibacterial/antifungal as needed
What tests should you do in abnormal hair loss?
1st: CBC, ferritin, TSH, microscopic exam and fungal culture (if suspected)
2nd: Scalp biopsy, ANA, androgens
What is depigmentation of the hair shaft caused by?
Protein or copper deficiency
How do you treat itching from PBC?
Bile acid binding resin (cholestyramine or colestipol), opioid antagonists (naloxone)
What endocrine disorders can present with itching?
Thyrotoxicosis, hypothyroid, diabetes
What type of cancer can be associated with itching?
Gastric carcinoid because of histamine flush
What drugs are associated with Steven Johnson syndrome?
Carbamazepine, phenytoin, allopurinol, lamotrigine, NSAIDs, sulfa
Rx: Identification of culprit drug, supportive care on burn unit or ICU, ophthalmology consult
Life threaning because of multisystem involvement
Acute life threatening mucocutaneous disorders with extensive necrosis and detachment of the epidermis
What is the treatment for shingles?
Often supportive
Treat if severe or disseminated
Give oral antiviral if initiated within 72 hours to reduce pain, viral shedding and healing time
TOPICAL antiviral is of no benefit
Clusters of erythematous papules and vesicles commonly following pain in a unilateral dermatomal distribution
What tests are done for the diagnosis of herpes simplex?
Tzanck smear - look for multinucleated epithelial cells
Viral culture
Viral PCR
Antibody testing of fluid from base of vesicle
HSV 1 = oral HSV 2 = genital sometimes oral
What is a common initial presentation of pemphigus vulgaris?
Mouth ulcers
Look for pts with painful skin or oral mucosa lesions
Itching is uncommon
Serious autoimmune blistering diease affecting pts 50-60 yo
How do you differentiate pemphigus vulgaris from bullous pemphigoid?
PV usually starts in the oral mucosa and move across the face and scalp, BP will start at the extremitites towards the flexural surfaces and trunk
PV middle aged (POSITIVE nikolsky), BP elderly (NO nikolsky)
PV autoAB against desmoglein vs BP autoAB against hemidesmisomes
Autoimmune bullous skin disease affecting middle aged or elderly
PV may require hospital admission, BP can generally be treated with topical and/or oral steroids or methotrexate, azathioprine
What is the classic finding of dermatofibroma?
Dimple sign
Common button like nodule presenting on extremities
Clinical features of malignant melanoma
Asymmetry
Border irregularities
Color variation
Diameter > 6 mm
Evolution
Hypertrophic scar vs keloid
Hypertrophic scars are confined to the original injury site vs keloids which extended beyond the original injury site
How does BCC present?
Basal cell carcinoma
Pearly papule or nodule with peripheral telangiectasias
Lots of other presentations possible but this is MC?
What should CDKN2A mutation make you suspect?
Malignant melanoma
Side effects of isotretinoin
Tertaogen, depression, suicidal ideation
Warn patients
Rosacea vs acne
Acne has comedones where as acne does
How to treat psoriasis?
Skin:
Medium - high potency corticosteroid cream or ointment
Calcipotriol ointment
Tar
Anthralin
Tazarotene gel or cream
Intralesional triamcinolone
Phototherapy
Methotrexate, acitretin, cyclosporine
Scalp:
Tar shampoo
Topical corticosteroid lotion, solution, foam
Calcipotriol solution
Tazarotene gel
Face:
Low potency corticosteroid cream or ointment
Tacrolimnus ointment
Auspitz sign: scale removal = appearance of minute droplets of blood
Chronic, recurrent inflammatory skin condition with abnormal epidermal differentiation and hyperproliferation
Lichen planus pnemonic
Acute or chronic inflammatory disorder affecting the skin, mucous membranes, and nails
Plantar
Purple
Pruritic
Polygonal
Papules
Mainly seen on inner wrists, torso, extremities
Sometimes present as white reticulated lesions of mucosal surfaces (lips and buccal mucosa)
ASSOCIATED WTIH HEPATITIS C SOMETIMES - SCREEN PTS
Tx: Difficult. Try corticosteroid creams. Maybe systemic agents if bad.
Eczema vs psoriasis
Eczema: ill defined, itchy, microvesicles, lichenification
Psoriasis: well defined, silvery, symmetric, salmon red
