Histology Helps Diagnosis Of Hair-Plucking Condition

"The combined utilization of clinical and histological findings in the diagnosis of trichotillomania"

By Mark Pownall

There are specific histological findings that are diagnostic of trichotillomania, the chronic psychiatric disorder in which patients pull, twist, pluck and otherwise remove their own hair in a traumatic and bizarre pattern.

Patients may deny the hair removal (in some cases the twisting and pulling may be subconscious) and insist it is a disorder such as alopecia (which trichotillomania may resemble).

A review of 28 scalp biopsies from 26 patients (24 female, two male) found trichomalacia (incompletely keratinized, distorted, and pigmented hair shafts) was a major criterion for diagnosis, as was pigmented casts.

The researchers looked at multiple vertical sections. Evaluation of the specimens was undertaken using special stains.

Researchers at The Cleveland Clinic Foundation, Cleveland, Ohio, United States found trichomlacia in 57 percent of the biopsies and pigmented casts in 46 percent.

Unspecific histology findings included follicular plugging, a decreased number of follicles, reversed antigen:telogen ratio, a decreased number of sebaceous glands, melanoderma, an elevated number of fibrous tracts and vellus hairs. The researchers also found superficial inflammation of the skin, evidence of hemorrhage and presence of hair granulomas.

They point out that the condition most often affects young people, but that it tends to be middle-aged and older people who have diagnostic biopsies.

They suggest that, together with clinical suspicion of trichotillomania, trichomalacia and pigmented casts are major criteria when coming to a diagnosis.

Journal of Cutaneous Pathology 2002; 29: 207-214.