What caused the total hair loss in this young boy?

Hair loss is devastating at any age, even for older persons with hereditary predisposition. But it is especially troubling for children, in whom alopecia is surprisingly common. But losing all of one's hair at an early age is another thing altogether. Such was the case with this 4-year-old boy who, 2 years earlier, had presented with two round 3-cm areas of complete hair loss on his left parietal scalp.

The condition was, as is often the case, misdiagnosed as ringworm of the scalp and was treated accordingly but to no avail. The boy was then referred to dermatology. He never had any symptoms with his condition and had no family history of similar problems. He was an atopic child, with seasonal allergies, asthma, and eczema. Both of his parents were natives of Mexico.

The boy's lesions exhibited complete and total hair loss in round areas, with no other skin changes; no scaling, redness, edema, or scarring were seen in these areas. The hair loss was particularly prominent around the posterior periphery of the scalp as the condition progressed. Over time, despite a number of treatments, the problem worsened to the point that all of the patient's scalp hair was totally gone (see Figure 1). Fortunately, he retained hair elsewhere, such as his eyelashes, eyebrows, and on his extremities.

Factors present in this case have been noted to predispose persons to an irreversible outcome called alopecia totalis.