Evaluation of human herpesvirus type 8 infection in childhood Langerhans cell histiocytosis

The etiology of Langerhans cell histiocytosis (LCH) is unknown. Viral causes, including human herpesvirus type 6 (HHV6), have been suggested but remain unproved. The recently discovered human herpesvirus type 8 (HHV8), the cause of Kaposi's sarcoma, infects dendritic cells in the bone marrow associated with multiple myeloma. Evidence for an association of HHV8 infection with LCH in children was studied by two approaches: indirectly by HHV8-specific serologic assays and directly by detection of HHV8 sequences using polymerase chain reaction in affected bone marrow samples. Using three different assays specific for HHV8 antibodies, 3 of 10 (30%) children with LCH had detectable HHV8 antibodies, which was not different from the prevalence of 5 of 30 (17%) in healthy controls of similar age (P = 0.65). Of bone marrow samples from three additional children with LCH, all had amplifiable DNA but were negative for HHV8 sequences, These studies of a small number of patients do not demonstrate an increased prevalence of HHV8 infection in children with LCH, and they do not suggest a causal role for HHV8 in the etiology of LCH. Am, J. Hematol, 64:237-241, 2000. (C) 2000 Wiley-Liss, Inc.