Acute lymphoblastic leukemia. Association with vasopressin-responsive diabetes insipidus

A rare case of acute lymphoblastic leukemia presenting with vasopressin-responsive diabetes insipidus (DI) is reported. The patient presented with polydypsia and polyuria of 9 L/day. Findings from special investigations of the CNS, including brain scan, computerized tomographic scan, EEG, and lumbar puncture were within normal limits. The patient's condition improved substantially after receiving vasopressin injections and later chlorpropamide. The incidence and underlying mechanism of this rare complication of acute leukemia are reviewed, and the response of DI to chlorpropamide is discussed briefly. In this patient it is presumed that the DI was caused by leukemic infiltration of the supraopticohypophyseal tract, posterior pituitary, or hypothalamus.