Diabetes insipidus and Langerhans cell histiocytosis: A case report of reversibility with 2-chlorodeoxyadenosine

Diabetes insipidus (DI) is the most common manifestation of central nervous system involvement in Langerhans cell histiocytosis (LCH). Patients with LCH involving the head and neck region are reported to have about a 40% lifetime chance of developing DI. The clinical and biochemical diagnosis of DI is sometimes supported by the absence of the posterior pituitary bright signal on magnetic resonance images. Cladribine (2-chlorodeoxyadenosine, 2-CDA) has been reported as an active drug in children and adults with relapsed or refractory LCH. The authors report the successful reversal of DI in a 3-year-old child with established LCH using 2-CDA.