8533 Salt on the Kidneys A case of DDAVP induced arginine vasopressin resistance

Abstract Disclosure: M.M. Jordan: None. J.R. Islam: None. R. Hassan: None. A 63-year old female with a history of head trauma complicated by polyuria and excessive fatigue diagnosed with central DI and started on treatment with oral Desmopressin. She had no other known pertinent medical history. Patient was lost to follow-up with an eventual visit to the emergency department with complaints of bilateral leg cramps, nausea and persistent headaches. She was noted to have been initiated intranasal desmopressin in addition to oral DDAVP. On initial lab work, Sodium was 114 along with acute kidney injury. She was admitted to ICU and treated with hypertonic saline. DDAVP was withheld until sodium normalized and stabilization of renal functions. GFR still remained impaired on discharge at 40 mL/min/1.73m*2. She was then discharged on DDAVP with reestablished follow up in the endocrinology clinic with complaints of persistent polyuria. Once more, she was sent to the emergency room and was admitted for acute renal injury secondary to dehydration in the setting of polyuria and altered mentation. Upon review of her medications, the patient continued both oral and inhaled DDAVP. No other medications or supplements were reported. During this subsequent hospitalization, sodium remained between 131-135 with urine output 4.5L/ day despite increasing doses of oral DDAVP and oral sodium supplementation. At which point, suspicion for mixed DI was hypothesized (central DI and arginine vasopressin resistance). Other causes of polyuria were ruled out. Labs for persistent AKI revealed gross proteinuria. Renal biopsy was performed during hospitalization which showed acute to chronic vascular thrombotic microangiopathy and focal segmental glomerulosclerosis with collapsing features. Extensive workup for chronic infections, autoimmune conditions and hematological malignancies were negative. This showed concerns for possible DDAVP induced renal injury. Presentation: 6/2/2024