WASHINGTON – Potentially puzzling hair diseases might be one of three emerging types of alopecia: psoriatic, frontal fibrosing, and permanent chemotherapy induced, according to Dr. Leonard Sperling.
"You have a good chance of seeing these in the coming year," he said.
Psoriatic alopecia claims features of both cicatricial and noncicatricial alopecia, said Dr. Sperling of the Uniformed Services University of the Health Sciences, Bethesda, Md. "It is a histological mimic of alopecia areata," he noted.
However, sebaceous gland atrophy is evident on histology and is a dependable diagnostic feature. "That’s what sets this disease apart," Dr. Sperling said.
A clinical differential diagnosis of psoriatic alopecia may include tinea capitis, chronic cutaneous systemic lupus erythematosus, seborrheic dermatitis, syphilitic alopecia, and psoriasis plus alopecia areata, he said.
Psoriatic alopecia is not new; a case was reported in 1972 (Br. J. Dermatol. 1972;87:73-7).
Clinical studies of treatment outcomes are limited, but one review of data from 47 cases of psoriatic alopecia showed that most patients had complete hair regrowth, although five patients developed residual scarring, Dr. Sperling noted (Dermatology 1992;185:82-7).
"The prognosis for hair regrowth seems to be favorable, but we have more to learn about this condition," he said.
Another emerging hair disease, psoriatic alopecialike reaction to tumor necrosis factor–inhibitor therapy is becoming increasingly common, Dr. Sperling said.
"If you haven’t seen this yet, I predict that you will, as the biologics are more utilized," he said. All the TNF-alpha inhibitors have been associated with this.
It is psoriasis from hell.
"The follicular findings resemble those seen in alopecia areata, in that there is a lot of hair miniaturization" and inflammation, Dr. Sperling said. Numerous different plasma cells and eosinophils are evident on histology, which would be unusual in alopecia areata, he noted. Atrophy of the sebaceous glands also is evident. Recognizing the role of the underlying drug is important to make the diagnosis, he added.
The reason for the atrophy of the sebaceous glands in these cases, as in patients with psoriatic alopecia, remains unknown, Dr. Sperling said.
Frontal fibrosing alopecia is becoming more common, "It’s like an epidemic," said Dr. Sperling. It is becoming more common, especially in the black community, although it was historically described in postmenopausal white women, he said. Frontal fibrosing alopecia can be mistaken for traction alopecia in black women in particular, he noted. However, it can be distinguished from traction alopecia by the loss of eyebrow hair, which might be a clue to consider a biopsy. "The histology is what you would expect in lichen planopilaris," he noted.
Fibrosing alopecia in a pattern distribution is another condition that might be mistaken for lichen planopilaris, Dr. Sperling said. The pattern of hair loss resembles common balding, "but there is inflammation in the zone of thinning," he said. If a biopsy also shows lichenoid changes and obliteration of follicles, consider a diagnosis of fibrosing alopecia in a pattern distribution. "A lot of the inflammation is concentrated around miniaturized hair follicles," he said, but terminal hair follicles are involved as well.
Permanent chemotherapy-induced alopecia occurs in some chemotherapy patients.
"A sizable number of chemotherapy patients develop some type of permanent hair loss after treatment," Dr. Sperling said. Data from biopsies have shown areas of permanent hair loss, but also telogenlike structures, with a curious, amoeboid shape, he said. However, similar structures have been identified in patients with linear morphea, suggesting that these features are not uniquely characteristic of postchemotherapy permanent alopecia, he said.
Instead, they seem to be some sort of end-stage marker for a follicle that isn’t going to grow back, he said.
Dr. Sperling said he had no relevant financial conflicts.
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