Pigmentation, Hair, & Nail Disorders Flashcards
Vitiligo
Idiopathic death(?) of melanocytes
S/Sx: Patchy/irregular loss of pigmentation, often symmetrical
Causes: Associated w/autoimmune dz such as thyroid dz, pernicious anemia, SLE, and Addison’s dz.
Dx: PE. Run thyroid fxn test, CBC, and fasting blood glucose
DDx: Tinea versicolor, postinflammatory hypopigmentation, chemically induced depigmentation, pityriasis alba.
Melasma/cholasma
Hyperpigmentation of face in pregnant women or those using OCP. More common with darker skin. Occurs with melanin increase from estrogen stimulation + UV light. Fades incompletely.
DDx: postinflammatory hyperpigmentation
Lentigines (Lentigo)
Flat, tan/brown spots on sun-exposed areas usu. face or hands due to chronic sun exposure.
Alopecia (scarring & non-scarring)
Baldness!
Non-scarring alopecia-
Male-pattern = androgenic
Female-pattern = androgenic/beginning at menopause
Diffuse = dx by pulling hairs >5w/bud (?) Triggered by weight loss/stress/pregnancy/illness
Toxic = chemotherapy
Alopecia areata = circular patches of complete hair loss anywhere on body. Autoimmune, toxic, genes, infections, drugs & vaccinations have been implicated in triggering it.
Trichotillomania = pulling out own hair
Scarring alopecia-
Causes = cutaneous lupus, deep bacterial infection, ulcers, granulomas, syphilis, tinea
Dx: Ratio of anagen & telogen hairs assessment. Occasional biopsy needed. *look for underlying cause.
Histruism
Excess hair in females in areas not normally hairy
Dx: Serum free/total testosterone, DHEA sulfate, FSH, LH, prolactin
Onychomycosis
Fungal infection of mail plate or bed
Cause: dermatophytes and yeast. Risks = old age, swimming, tine pedis, psoriasis, diabetes, immunodeficiency, genetic predisposition, living w/family members who have it.
S/Sx: Nails have asx patches of white, brown or yellow color & deformity. May thicken.
Dx: appearance, KOH microscopy. If negative, do culture & microscopic exam of clippings
DDx: nail distrophies = psoriasis, eczematous conditions, trauma, lichen planus, iron deficiency
Paronychial infections
Periungual infection
S/Sx: develops along nail margin, becomes painful, warm, erythematous & swollen. Pus along the nail margin or beneath nail.
Dx: PE
