Multiple cutaneous plexiform schwannomas as initial presentation of neurofibromatosis 2 in a 9-year-old.

Neurofibromatosis 2 (NF2) is an autosomal-dominant disease caused by genetic mutations of the NF2 gene on chromosome 22. Patients are often diagnosed according to the presence of bilateral vestibular schwannomas and other tumors in the brain and spinal cord. In children, NF2 can present early with ocular findings and cutaneous tumors. We report here a 9-year-old girl who presented with multiple pigmented, slightly tender plaques on her scalp, face, and back that were revealed by histopathology to be plexiform schwannomas. We suspected NF2 and sent the patient's blood for genetic testing, which confirmed our diagnosis.

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. Electron microscopic studies of a follicular lesion showed extracellular viral particles suggestive of a polyomavirus within the central follicular keratotic debris. DNA polymerase chain reaction (PCR) and gene sequencing studies, performed on the tissue of the microscopic slide and paraffin block, for the recently identified TS-associated polyomavirus (TSPyV) resulted as positive for TSPyV. PCR for the Merkel cell polyomavirus was negative. To date, this case is unique in representing the first case of TS confirmed by electron microscopy in which a related viral pathogen has been molecularly identified. An additional 19 reported cases classifiable as TS are tabulated and reviewed.

Scaly, circular papules in a healthy toddler.

A 2-year-old boy presents with asymptomatic keratotic papules on his hands and feet. A biopsy is performed and he is confirmed to have punctate porokeratotic keratoderma. A discussion of punctate porokeratotic keratoderma is provided along with treatment options.