Hair and nail disorders

Question 1

Androgenic alopecia

Answer 1

50% of men and women by age 50
each follicle genetically marked to become bald (or not)
uptake, metabolism and 5-alpha reduction of testosterone is increased to dihydrotestosterone
can be inherited from either the maternal or paternal side of the family

Question 2

Androgenetic alopecia tx

Answer 2

oral finasteride
topical minoxidil solutio
hair transplant surgery

Question 3

Alopecia areata

Answer 3

circumscribed circular patch or patches; periphery may show short broken hairs
exlamation point hairs which taper proximally - pathognomonic
asymptomatic, but there may be paresthesias or tenderness
may affect eyebrows, eyelashes and beard
course is unpredictable but early onset/atopy may indicate a lengthy course with increased incidence of alopecia totalis
50% resolve in 1 year without treatment
25% family history
8% association with thyroid disease, 4% vitiligo
nail changes (pitting etc) can occur in up to 40% of alopecia areata cases

Question 4

Trichotillomania

Answer 4

repetitive pulling, plucking of hair
patchy, unnatural pattern, peripheral portions are usually spared
less than 5% have deep-seated psychological disorders
may be life-threatening if there is concomitant trichophagy
trichobezoars can cause partial obstruction of the intestine

Question 5

Tinea capitis

Answer 5

Most common cause in BC: Microsporum canis (found on cats/dogs) - not contagious from human to human
second most common = Trichophyton tonsurans (anthrophilic) - contagious from human to human
Cases may be non-inflammatory or inflammatory (can be secondarily infected with staph)

Question 6

Tinea capitis diagnosis

Answer 6

KOH scraping
mycologic culture
Wood’s lamp - fluorescence due to pteridine production

Question 7

Telogen effluvium

Answer 7

excessive shredding of normal club hairs brought on by stresses
parturition, febrile illness, stress, crash diets, drugs: metoprolol, anticoagulants, antithyroid drugs, sodium valproate
factors cause termination of anagen into catagen and then telogen
2-4 months, telogen hairs are pushed out
50000 hairs must be lost before visible thinning (50% of normal scalp hair)
normal regrowth in 6 months

Question 8

Anagen efluvium

Answer 8

decrease/complete discontinuance of proliferation of matrix cells of the hair shaft
occurs afew days to weeks of the “insult”
chemotherapy/radiation

Question 9

Scarring (Cicatricial) alopecia

Answer 9

far less common than nonscarring alopecias, but important to recognize because of potential for irreversible permanent hair loss
Discoid lupus erythematosus
Lichen planopilaris

Question 10

Onychomycosis

Answer 10

Fungal infection
great toenail extremely prone to infection
fingernails - only occur in previously traumatized or when nail involvement is part of tinea mannum
olycholysis and subungual hyperkeratosis
Mostly due to Trichophyton rubrum, diagnosis by culture
Treatment - terbenafine or itraconazole (oral)

Question 11

Onycholysis

Answer 11

separation of nail plate from nail bed

Question 12

Psoriatic nails

Answer 12

more serious nail dystrophies often accompanied by inflammatory, arthritic changes in the distal interphalangeal joint
extremely difficult to treat

Question 13

Beau’s grooves

Answer 13

1mm wide depression in the nail plate which extend horizontally from one lateral nail groove to the other
all nails are simultaneously affected
most commonly develop following dramatic illnesses such as MI and periods of high fever or malnutrition

Question 14

Clubbing

Answer 14

Lovibond’s angle >180 degrees
most commonly seen with chronic pulmonary/cardiopulmonary disease but also occurs with some tumours, especially those of the lung parenchyma

Question 15

Periungual warts

Answer 15

often distort the nail plate
in most instances, the dystrophy is not permanent and then ail plate returns to normal following therapeutic or spontaneous resolution of the warts

Question 16

White banding of nails

Answer 16

horizontal white banding or opacification occurs in hypoalbuminemia accompanying chronic hepatic or renal disease

Question 17

Brown banding of nails

Answer 17

vertical - secondary to nevus or melanoma

horizontal - Addison’s disease/cancer chemo

Question 18

Splinter hemorrhages

Answer 18

Thin, dark red lines 1-3 mm in length
represent small hemorrhages at the jxn of the nail plate and the nail bed
move out as the nail grows; seen with bacterial endocarditis, trichinoisis, but frequently seen in normal individuals

Question 19

Candida paronychia

Answer 19

most common cause of paronychial inflammation and swelling of the fingers
seen in dishwashers, bartenders and waitresses
characterized by: lack of pain, lack of warmth, absence of pus, chronicity

Question 20

Bacterial paronychia

Answer 20

usually caused by Staph

redness, warmth, swelling and tenderness