Lymph node microscopic findings in Wiskott-Aldrich syndrome.

A 20-year-old man with a history of Wiskott-Aldrich syndrome (WAS) underwent excisional biopsy of a femoral lymph node for evaluation of lymphadenopathy. Histologic examination showed paracortical expansion by a lymphohistiocytic infiltrate, and reactive follicles with regressive changes. The interfollicular histiocytes had clumped nuclei and showed occasional emperipolesis. Special stains were negative for infectious organisms. The microscopic findings in this lymph node are related to the underlying WAS. Emperipolesis has previously been reported in lymph nodes of patients with WAS. Recognition of reactive microscopic features in lymph nodes of these patients is important, as they are at increased risk for lymphoproliferative disorders.