Why it happens
In alopecia areata, T lymphocytes mistakenly identify the follicle as foreign and trigger an inflammatory reaction around it, interrupting growth. The follicle enters a resting state but remains intact — which is why spontaneous recovery is possible.
There's a genetic component and an association with other autoimmune diseases, particularly thyroid disease. Episodes of intense stress, infections or hormonal changes often act as a trigger.
How it presents
The typical picture is the sudden appearance of one or more round, hairless patches on the scalp or beard, without pain or flaking. Some patients notice tingling or itching in the preceding days.
- Patchy alopecia areata — the most common form, with one or a few affected areas
- Alopecia totalis — loss of all scalp hair
- Alopecia universalis — loss of all body hair
- Ophiasis — a band of hair loss along the nape and temples, which responds more slowly
- Nail changes, particularly fine pitting, present in a significant proportion of cases
Diagnosis and treatment
Diagnosis is clinical, supported by trichoscopy — magnified examination of the scalp — which reveals characteristic signs such as yellow dots and exclamation-mark hairs. Blood tests are requested to screen for thyroid disease and associated deficiencies.
Treatment involves topical or intralesional corticosteroids, topical immunotherapy in more extensive cases, and, more recently, JAK inhibitors in severe cases followed up in dermatology consultations. Mesotherapy and PRP can support the recovery phase by improving the follicle's environment.
Prognosis
In single, recent patches, spontaneous recovery is common — most of these cases regrow hair within the first year, with or without treatment. Extensive forms, those with childhood onset, or the ophiasis type have a less predictable course and a tendency to recur.
Because the follicle isn't destroyed, a hair transplant isn't indicated while the disease is active — the priority is to control the inflammation.