A punch biopsy specimen of skin from the patient's back demonstrated an enlarged hair follicle containing a small segment of hair shaft (Figure 2). The bulb was abnormal in that it lacked a papilla. Moreover, the matrical cells were disordered and merged with an expanded inner root sheath with cells containing large trichohyaline granules (Figure 3). The upper segment of the follicle, including the infundibulum, was distended and plugged with keratin derived from inner root sheath cell cornification. Mild perifollicular lymphocytic inflammation was also observed. The histopathologic findings, in the context of the clinical setting, were diagnostic of TS. Follicular dilatation, absence of a papilla, inner root sheath cell trichohyaline granules, and infundibular keratin plugs are typical histologic features of TS. The presence of a residual segment of hair shaft material is uncommon but has been reported in up to one-fourth of cases of TS.1 There was no clinical improvement during a 2-week trial of topical acyclovir cream, 5%. Since then, however, there was has been spontaneous gradual improvement of the lesions, with 50% resolution 10 months after the completion of chemotherapy.
Keratotic “Spiny ” Papules in an Immunosuppressed Child —Diagnosis. Arch Dermatol. 2011;147(10):1215–1220. doi:10.1001/archdermatol.2011.286-b
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