Alopecia areata is the second most common type of non-scarring alopecia that affects evenly men and women, but also very often affects children. It is an autoimmune inflammatory skin disease that causes hair loss on the scalp, but also on the face (beard, eyebrows, eyelashes) and body. It is associated very often with other autoimmune disorders such as lupus erythematosus, vitiligo, or autoimmune thyroid disease. Many patients with a family history of alopecia areata also have a personal or family history of atopy, Down’s syndrome and other autoimmune diseases. Familial cases of alopecia areata are often characterized by a poorer prognosis, more rapid progression, more frequent relapses, and greater resistance to therapy.
Alopecia areata usually starts with one or a few round patches of hair loss on the scalp. If it progresses to total scalp hair loss the condition is known as alopecia totalis. Furthermore, if it affects the entire body then it is named alopecia universalis. Variants of this disorder include ophiasis in which hair loss affects the occipital scalp, diffuse form of areata, and “overnight graying” in which pigmented hair follicles are attacked with the result that preexisting gray hairs are demasked.
The way to diagnose alopecia areata is: taking a detailed family history (history of atopy or any other autoimmune disease), clinical evaluation (hairless patches or large alopecic areas in normal-appearing skin)
dermatoscopy along with trichoscopy (black and yellow dots and “exclamation mark” appearance of the hairs), pull test (positive), laboratory testing (thyroid-function test and tests for thyroid antibodies) and biopsy (a dense, peribulbar lymphocytic infiltrate-“swarm of bees”).
Although diagnosing alopecia areata is not that difficult, treating surely is. However, good news is that this condition has a high rate of spontaneous remission. Very often after 6 to 8 weeks hair regrowth begins.
At present, only two therapies have reached the level of evidence-based medicine: intralesional injections of glucocorticoids and the induction of contact allergy.
Glucocorticoids could be applied in three ways:
- Topically as a high-potency cream like Clobetasol under occlusion. Topical corticosteroids frequently fail to enter the skin deeply enough to affect the hair bulbs, which are the treatment target
- Intradermal injections of triamcinolone-acetonide every 2-6 weeks. Side effects include pain, and the risk of localized skin atrophy and depigmentation. Relapses are frequent after treatment has been discontinued
- The use of systemic glucocorticoids is limited mainly because of their severe side effects. However, the best response can be achieved with high-dose intravenous methylprednisolone.
The second line therapy both for adults and children is the induction of contact allergy with dithranol (anthralin), an antipsoriatic agent. Dithranol (0.2 to 0.8%) should be applied for 20 to 30 minutes daily as the initial, short-contact therapy, with the length of contact gradually increased by 10 minutes every 2 weeks to a maximum of 1 hour or until a low-grade dermatitis develops.
Some medications are also used such as minoxidil and topical immunotherapy-cyclosporine or tacrolismus. The use of lasers and PRP (platelet rich plasma and growth factors) in stimulating hair growth in alopecia areata has become a very common way of treatment as well.
Prognosis of this disorder is very difficult to give. Hair may grow back and then fall out again. Usually a person reacts to a stressful event with patchy hair loss and it becomes their way of coping with a stress. If alopecia areata occurs before puberty, there is much greater chance of chronic recurrence of the condition. If undergoing any treatment, one has to be very dedicated to it and patient.