Ch 87: Alopecia Areata Flashcards
Characteristic hallmarks of AA
(+) black dots (cadaver hairs, point noir)
(+) exclamation point hairs
Nail findings in AA
(+) nail pitting
(+) sandpaper-like appearance
Conditions associated with AA
Cataracts, thyroid disease, vitiligo, atopic dermatitis, psoriasis, Cronkhite-Canada, Down syndrome
Main drivers of disease pathogenesis (2)
1) Autoactive cytotoxic CD8 T cells, 2) interferon-gamma-driven immune response
* Cytotoxic subset: CD8+ NKG2D+ T cells
Risk factors for AA
Family history
Major emotional stress
Antioxidant-oxidant imbalance
Dermatoscopic findings in AA
(+) follicular ostia
(+) exclamation point hair
(+) black dots/cadaver hair
(+) yellow dots
Phenomenon in which all pigmented hairs fall out and the patient is left with only white hair
Canities subita
Diagnostics to order for AA
4mm punch (horizontal section) Thyroid function tests Iron/vitamin deficiencies
Histopathologic findings in AA (general)
(+) generalized miniaturization
(+) marked increase in catagen and telogen hairs
*HP features are STAGE-DEPENDENT
Histopathologic findings in AA (acute stage)
(+) “swarm of bees” - peribulbar immune infiltrate centered around the hair bulb (mostly CD4, CD8, NK cells +/- mast cells, plasma cells, eos)
Differentials
Temporal triangular alopecia Tinea capitis Early scarring alopecia Trichotillomania Secondary syphilis (alopecia areolaris) Androgenetic alopecia Telogen effluvium Anagen effluvium
Prognosis: % of affected individuals having a solitary episode
25%
Spontaneous regrowth is common, diff body areas appear to regrow independently
Prognosis: % of individuals with partial regrowth by 1 year
60% (but often followed by repeated episodes of hair loss)
Prognosis: % of individuals with relapses within the 1st year
40%
Poor Prognosis (4)
Involvement of occiput/hairline
Chronic relapsing course
Presence of nail changes
Childhood onset
Prognosis:
% becoming AA totalis
% becoming AA universalis
RF for above
5% AA totalis
1% AA universalis
Younger age of onset, hair loss from trunk/extremities
Treatment for <10yo
Topical corticosteroids (mometasone) +/- Minoxidil 5%
Treatment for >10yo, <50% scalp involvement
ILSI (first-line)
Class I CS under occlusion
Class II +/- Minoxidil 5%
*If unresponsive, topical immunotherapy
Treatment for >10yo, >50% scalp involvement
Topical immunotherapy (DPCP or SABDE) JAK inhibitors ILSI Platelet-rich plasma injections Scalp prosthesis
Tx: ILSI (dosing, frequency, expected response)
2.5 to 10mg/mL Q4-6 weeks
15 to 40mg injected per session
Initial response in 4 to 8 weeks
*If no regrowth after 4 mos, consider other options.
Tx: Systemic Corticosteroids (dosing, pulse, prognosis)
Pred 20 to 40mg OD, taper to 5mg in a few weeks
Pulse: Pred 100 to 300mg, or Methylpred IV 250mg
*Regrown hair frequently FALLS OUT again when treatment is discontinued. Does NOT alter long-term prognosis.
Tx: Prostaglandin Analogs
Latanoprost, Bimatoprost - for AA of eyelashes, eyebrows, adjuvant tx
Tx: Anthralin 0.2% to 0.1% cream/ointment (dosing, expected response)
First 2 wks: 20-30 mins OD
Next 2 wks: 45-60 mins OD, overnight if tolerated
New hair growth in 2-3 mos of treatment. Good choice for children. NOT suitable for eyebrows/beard.
Tx: Anthralin 0.2% to 0.1% cream/ointment (MOA, SE)
Irritant, nonspecific immunomodulating effect (anti-Langerhans cell)
SE: irritation, scaling, folliculitis, regional LAD, brown discoloration of skin, staining of clothes
Tx: Topical Immunotherapy (MOA)
- Diphenylcyclopropenone 2% solution
Creation of contact dermatitis (decrease in peribulbar CD4/CD8 lymphocyte ratio, shift in position of T-lymphocytes away from perifollicular area to interfollicular area and dermis)
Tx: Topical Immunotherapy (MOA)
- Diphenylcyclopropenone 2% solution
2% solution to sensitize small scalp area 1wk prior to tx, then 0.0001% weekly. Do NOT wash scalp for 48 hours after tx, UV protection. Increase concentration per week until with mild erythema and mild itching.
Max dose: 2%
SE: severe contact eczema, discoloration (vitiligo/hyperpigmentation); Extreme caution in AD and dark skin types
Tx: Photo(chemo)therapy (prog)
UVB or PUVA
*very high relapse rate
Tx: Cyclosporine (dosing, SE)
4 to 6 mg/kg/day (+/- pred)
SE: elev LFTs, elev cholesterol, headaches, dysthesia, fatigue, diarrhea, gingival hyperplasia, flushing, myalgia
Tx: Janus-Kinase inhibitors
Inhibit autoreactive CD8 T-cell infiltrate
Oral baricitinib, tofacitinib citrate (FDA-app for RA) Oral ruxolitinib (FDA-app for myelofibrosis)
