Viral-associated trichodysplasia spinulosa: a case with electron microscopic and molecular detection of the trichodysplasia spinulosa-associated human polyomavirus.

Trichodysplasia spinulosa (TS) is a folliculocentric and clinically papular dermatological disorder occurring in the setting of immunosuppression typically in association with solid organ transplantation or hematolymphoid malignancies. We report the occurrence of TS in a 7-year-old girl with Down syndrome and pre-B-acute lymphoblastic leukemia who was completing chemotherapy at onset. The patient's affected follicles were dilated by an expansion of a dystrophic follicular inner root sheath cell population displaying enlarged trichohyaline cytoplasmic granules and progressing centrally to keratotic and parakeratotic debris, and superficially demonstrating some diminutive hair shaft-like material within the keratotic spicules.

Lipoma arborescens of the hip.

Lipoma arborescens is a rare intra-articular lesion characterized by extensive villous proliferation of the synovial membrane and hyperplasia of subsynovial fat. Although it has been described as arising from traumatic, inflammatory, rheumatologic, developmental, and neoplastic causes, its etiology remains unknown. This article describes in detail--for the first time in the orthopedic literature-a case of lipoma arborescens of the hip.