Abstract: SA-PO716
A Deep Dive into Diabetes Insipidus
Session Information
- Fluid, Electrolyte, Acid-Base Disorders: Clinical - II
November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Fluid, Electrolytes, and Acid-Base Disorders
- 1102 Fluid, Electrolyte, and Acid-Base Disorders: Clinical
Authors
- Zeng, Billy, Kaiser Permanente, Oakland, California, United States
- Zheng, Sijie, Kaiser Permanente, Oakland, California, United States
Introduction
Central diabetes insipidus (DI) is a disease caused by absent antidiuretic hormones production, leading to symptoms of polyuria and polydipsia. Head trauma is a typical cause of central DI. We present a case of new onset partial central diabetes insipidus where recurrent scuba diving was considered a likely trigger.
Case Description
A 58-year-old female presented with polyuria, nocturia, and thirst for one month that started after an annual scuba diving trip. Past medical history was notable for anxiety. She was recently prescribed buproprion prior to these symptoms. Physical exam was unremarkable, serum sodium 145 mmol/L, serum osmolality 305 mOsm/Kg, 24-hour urine volume >2.8 L, and urine osmolality 180 mOsm/Kg. She was empirically started on DDAVP to relieve nocturia symptoms and scheduled for a water deprivation test. Nocturia symptoms improved immediately after started DDAVP. Water deprivation test (Figure 1) showed mild elevations of urine osmolality with water deprivation and substantial increase of urine osmolality with DDAVP administration indicative of partial central DI. An MRI was performed, showing an absent neurohypophysis on T1 sequence. According to the patient, a previous head MRI was normal. On further review of the patient’s social history, she went on annual scuba diving vacations for many years.
Discussion
To our knowledge this is the first report of central DI associated with scuba diving. Previous studies have shown that recreational diving can cause a reduction of 20% cerebral blood flow, decompression while ascending can also cause brain injury. We hypothesize that repeated exposure to such hypoxic conditions may have caused injury to the posterior pituitary, with potentially some injury associated with each dive until eventually enough posterior pituitary function was affected, resulting in dysfunction of antidiuretic hormone production or release.
Figure 1. Water deprivation test. Urine osmalality was measured each hour. DDAVP administered at hour 7.