Congenital self-healing reticulohistiocytosis. A new entity in the differential diagnosis of neonatal papulovesicular eruptions.

A case of congenital self-healing reticulohistiocytosis is described. The case is different from those previously described because papulovesicles, rather than the papulonodules that are usually characteristic of this disease, predominated. All lesions regressed within 2 months of presentation, and at 2-year follow-up, the patient continues to develop normally without recurrence of the eruption or progression to internal organ involvement. Electron microscopic examination revealed numerous Langerhans' granules admixed with myelinlike laminated dense granules characteristic of this disease. The unique physical presentation in this case, as well as the criteria used to differentiate this disorder from the more malignant forms of histiocytosis and other childhood papulovesicular eruptions, is emphasized.