#3500 CENTRAL DIABETES INSIPIDUS ASSOCIATED WITH ACUTE MYELOID LEUKEMIA

Abstract

Abstract Background and Aims Central Diabetes Insipidus (CDI) is a rare condition in which there is decreased release of antidiuretic hormone (ADH) from the posterior lobe of the pituitary gland resulting in polyuria. CDI is most commonly idiopathic with other known causes being primary or secondary tumors, cranial nervous system (CNS) infiltrative diseases, head trauma or neurosurgical procedures. Acute Myeloid Leukemia (AML) is rarely associated with CDI. We report a case of elderly male patient with recently diagnosed AML who developed polyuria due to CDI. Method Review of medical literature and hospital patient case workup based on reviewed medical literature. Results A 78-year-old male patient diagnosed with acute myeloid leukemia was started on treatment with Decitabine and Venetoclax 4–6 weeks prior to his hospitalization with chief complaints of back pain and oropharyngeal mucositis. The patient was also noted to have significant polyuria with hypernatremia during his hospitalization. His urine output ranged around 6–7 liters per day and his serum sodium levels were noted to be elevated to 162 mmol/L. 24-hour urine osmolality was calculated at around 1700 milliosmoles/day. Though patient's initial labs were suggestive of osmotic diuresis as a cause of his polyuria from ongoing hyperosmolar IV fluids input and significant increased oral dietary osmolar input, his polyuria persisted despite decreased total daily osmolar input. Further investigation with desmopressin suppression testing was notable for doubling of his urine osmolality with 10 mcg intranasal desmopressin administration with urine osmolality reaching to a peak of 447 mOsm/kg, indicating CDI as a reason for patient's ongoing polyuria. Patient's urine output as well as hypernatremia improved with initiating the patient on daily Desmopressin. MRI head with and without contrast ruled out any intracranial masses or infiltrative CNS diseases. Conclusion The pathogenic mechanism for association between CDI and AML is not completely clear, but it is thought to be secondary to infiltration of the central nervous system with leukemic cells, especially Sella Turcica, though this may not be evident on CNS imaging studies in all the cases, like in our patient. Polyuria can present in patients with AML either before or after the diagnosis of AML and sometimes it might be the only presentation in patients with AML which would lead to further workup and diagnosis of AML. Early identification of CDI in these patients lead to prompt management and avoidance of any significant electrolyte imbalances which could be sometimes attributed to patient's chemotherapeutic agents rather than to the patient's disease process itself.