Composition of the inflammatory infiltrate in pediatric penile lichen sclerosus et atrophicus (balanitis xerotica obliterans): a prospective, comparative immunophenotyping study.

Dermatopathological evaluation of pediatric preputial inflammatory disease rarely allows for specific diagnosis other than pediatric penile lichen sclerosus et atrophicus (balanitis xerotica obliterans, LSA/BXO). A prospective immunopathological study was performed on 20 consecutive, unselected, clinically and histopathologically confirmed LSA/BXO cases to determine the relative presence of T and B lymphocytes. There were seven cases with early stages of disease, eight with florid disease, and five with later stages of disease. Two ritual circumcision specimens and 12 specimens with non-LSA/BXO balanitis, collected during the same period, were used as controls. The infiltrate in LSA/BXO patients was wholly composed of T cells (positive with UCLH-1 antibody) in all cases. B cells (positive with L-26 antibody) were found only focally in small, discreet, easily recognizable (follicular or early follicle-like) aggregates, positioned slightly deeper than the band-like infiltrate of T cells. T cells were inconspicuous in 9 of the 12 control specimens. In the three other controls, T cells were much more obvious and these patients showed clinical features possibly suggestive of LSA/BXO in early, prediagnosable phases of development. We conclude that limited immunophenotyping may be a useful adjunct to diagnosis in pediatric cases in which only limited tissue is available or the disease may be more difficult to classify with confidence.