RT Journal A1 Esterly NB, Swick HM T1 CUtaneous letterer-siwe disease JF American Journal of Diseases of Children JO American Journal of Diseases of Children YR 1969 FD February 1 VO 117 IS 2 SP 236 OP 238 DO 10.1001/archpedi.1969.02100030238022 UL http://dx.doi.org/10.1001/archpedi.1969.02100030238022 AB Letterer-Siwe disease is a nonlipid reticuloendotheliosis of unknown etiology and is usually grouped with Hand-Schüller-Christian disease and eosinophilic granuloma as components of histiocytosis X.1 It typically occurs in infancy and, clinically, is the most generalized and serious of these conditions.2 In recent years, the prognosis of infants with Letterer-Siwe disease has improved, primarily due to more aggressive therapy with corticosteroids and antimetabolic agents.3,4 The patient described below is of interest because of her prolonged course and because involvement has apparently been confined to the skin.Report of a Case  The patient (JHH No. 121-91-97) was admitted to The Johns Hopkins Hospital in October 1966 for evaluation of a chronic and refractory skin eruption. She had been well until 8 months of age when she developed "cradle cap" which did not improve on treatment for seborrhea. By 16 months of age, there was diffuse involvement of the neck