Makindo Medical Notes

Related Subjects: |Atopic Eczema/Atopic Dermatitis |Psoriasis |Alopecia Areata |Alopecia

Exam shows circular area of nonscarring alopecia incidentally found in an adult patient

About

• Alopecia areata is an autoimmune condition characterized by patchy hair loss.
• 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

Poor prognostic factor for alopecia

• Extent of involvement (alopecia totalis/universalis)
• Younger age of onset, Family history, Atopy
• Ophiasis, Nail changes, Associated autoimmune disease

Investigations

• FBC, U&E, LFTs, Autoimmune screen

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 intralesional 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

References

• Alopecia Areata