Central precocious puberty in multisystem Langerhans cell histiocytosis: a case report.

The authors describe a girl with multisystem Langerhans cell histiocytosis (LCH) who developed central precocious puberty (CPP). At the age of 19 months she presented with otorrhea and polypoid formations in the ear canal; polyps were removed and LCH suspected. She subsequently developed diabetes insipidus with a documented lesion of the pituitary stalk; she received chemotherapy and began therapy with l-desamino-8-D-argininevasopressin. Growth hormone deficiency was diagnosed at the age of 4.4 years and GH replacement therapy started. The patient has been off therapy for LCH since the age of 6. Signs of pubertal development appeared at 7.5 years (bone age 8 years) and gonadotropin-releasing hormone analog (GnRHa) treatment was started. During the observation period she developed central hypothyroidism. Development of CPP during LCH is extremely rare; to the authors 'knowledge, no patient has been described so far. The authors believe that CPP was secondary to LCH and did not represent a casual finding, even in the absence of hypothalamic-pituitary axis involvement. The presence of preceding lesions producing excessive cytokine levels, with damage on the neurosecretory apparatus that inhibits the GnRH pulse generator, represents the most intriguing hypothesis. The possibility of CPP development should be considered during the follow-up of these patients.