Exam shows circular area of nonscarring alopecia incidentally found in an adult patient
About
- Alopecia areata is a chronic inflammatory disease which affects the hair follicles and sometimes the nails
- Affects 1 in 1000 people worldwide; in the USA
- Affects patients at all ages including children
Aetiology
- Alopecia areata is an organ-specific autoimmune disease targeting hair follicles
- Dystrophic changes of anagen follicles along with rapid progression of hair follicles from anagen to catagen and telogen phases are observed
Associations
- Pernicious anaemia, SLE, myasthenia gravis, rheumatoid arthritis
- PMR, ulcerative colitis, and lichen planus.
- Autosomal recessive disease autoimmune polyglandular syndrome type 1
- Down's syndrome or Turner's syndrome
Clinical
- Patches of hair loss on the scalp but any hair-bearing skin can be involved.
- Affected skin may be slightly reddened but otherwise appear normal.
- Short broken hairs (exclamation mark hairs) are frequently seen around the margins of expanding patches of alopecia areata.
- The nails are involved in about 10% of patients referred for specialist advice.
- Up to 25% progress to total loss of scalp hair (alopecia totalis, AT) or loss of the entire scalp and body hair (alopecia universalis, AU)
- Also thyroiditis and vitiligo may be seen
Investigations
- FBC, U&E, LFTs, Autoimmune screen
Poor prognostic factor for alopecia
- Extent of involvement (alopecia totalis/universalis)
- Younger age of onset
- Family history
- Atopy
- Ophiasis
- Nail changes
- Associated autoimmune disease
Management
- Alopecia areata is difficult to treat and few treatments have been assessed in randomized controlled trials
- Alopecia areata may cause considerable psychological and social disability and in some cases, particularly those seen in secondary care, it may be a chronic and persistent disease causing extensive or universal hair loss
- Potent topical corticosteroids are widely used to treat alopecia areata but there is little evidence that they promote hair regrowth. Folliculitis is a common side-effect of topical corticosteroid treatment.
- Depot corticosteroid injected intralesionally stimulates hair regrowth at the site of injection in some patient
- New treatment agents, such as excimer laser, low-dose recombinant interleukin 2, Janus kinase inhibitors, and simvastatin