Virus-associated trichodysplasia spinulosa.

Virus-associated trichodysplasia spinulosa (VATS) is a cutaneous eruption of spiny papules predominantly affecting the face that is associated with a distinctive histologic picture of abnormally maturing anagen follicles with excessive inner root sheath differentiation and hyperkeratotic infundibula. Ultrastructurally, intranuclear viral particles consistent with polyoma virus are found. Only 2 patients have thus far been reported. Both had developed the eruption after a kidney transplant. We report 2 additional cases of VATS. One is an 8-year-old boy who presented with facial papules after a kidney transplant. The other is a 19-year-old man with a history of acute lymphocytic leukemia who never had a transplant. He developed a papular facial eruption as well as alopecia. Light microscopic and ultrastructural examinations revealed a spectrum in the severity of the histologic alterations as well as the number of intranuclear viral particles. This report expands the range of pathologic alterations associated with VATS and documents for the first time that it can affect patients without a solid organ transplant. The similarity of the clinical and histologic features of VATS with those previously reported by others as cyclosporine-induced "follicular dystrophy" or "pilomatrix dysplasia" raises the possibility that the described phenomena may reflect the same entity. Increased awareness of the distinct histologic picture associated with VATS will likely lead to more frequent diagnosis of this underrecognized entity.