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Splitting hairs: the 'hamburger sign' in trichotillomania
Michael C Royer1, Leonard C Sperling
1Armed Forces Institute of Pathology, Washington, DC, USA. miachael.royer1@us.army.mil
Background:
A 43-year-old male presented with the clinical findings of patchy alopecia that contained persistent hair and re-growth of hairs of various lengths, consistent with trichotillomania. A biopsy was performed to confirm the diagnosis..
Results:
Histologic evaluation revealed findings consistent with trichotillomania, including trichomalacia. Several hair shafts also showed a vertically oriented split, which contained proteinaceous material and erythrocytes. Morphologically, these were reminiscent of a hamburger within a bun.
Conclusions:
The unusual finding reported in this case has not been previously reported. The "hamburger bun sign" provides an additional clue to traumatic injury in the evaluation of biopsies for trichotillomania.
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