Abstract: FR-PO0600
Diabetes Insipidus as a Cause of Hypernatremia in a Patient with Systemic Vasculitis: A Case Report
Session Information
- Fluid, Electrolyte, and Acid-Base Disorders: Clinical - 2
November 07, 2025 | Location: Exhibit Hall, 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
- Rayamajhi, Rabindra Jang, Baylor Scott and White Health, Temple, Texas, Temple, Texas, United States
- Badsha, Farrukh Sarmad, Baylor Scott and White Health, Temple, Texas, Temple, Texas, United States
- Goraya, Nimrit, Baylor Scott and White Health, Temple, Texas, Temple, Texas, United States
Introduction
In patients with systemic vasculitis, hypernatremia can be the earliest clue to diagnose diabetes insipidus (DI) and possible central nervous system (CNS) involvement. Here we present a rare case of DI associated with a patient with Behcet’s disease with PR3+ ANCA associated vasculitis.
Case Description
A 32-year-old male with a past medical history of rheumatoid arthritis, aortitis, syphilis, and deep vein thrombosis presented with a history of generalized body ache, fatigue, papular rashes over the body, and oral as well as urethral ulcers for last 2 weeks and unintentional weight loss of 90 lb in the last 4 months. He had scleromalacia perforans in his left eye, ground glass opacity in the chest CT with diffuse alveolar hemorrhage in bronchoscopy, and Proteinase 3 Antibodies positive in blood. Skin biopsy showed leukocytoclastic vasculitis involving small and medium-sized blood vessels with fibrin thrombi. Serum creatinine was normal with no blood or protein in the urine. After extensive interdisciplinary discussion, the patient was diagnosed with Behcet’s disease with PR3+ ANCA associated vasculitis. Meanwhile, the patient had a history of polyuria (6 to 8 liters of urine per day) for the last 2 to 3 years. He said he had to go around 50 times a day for urination. He used to drink a lot of water; however, recently, due to oral ulcers, he could not drink much water. Evaluation revealed hypernatremia of serum sodium 151 meq/L, high serum osmolality, and low urine osmolality. After giving desmopressin, urine osmolality increased by >50%. The brain MRI was normal, and serum copeptin was low. A diagnosis of central diabetes insipidus was made, and the patient was treated with desmopressin, initially injectable and later transitioned to oral tablets. With the treatment, the patient’s urine volume was decreased, serum sodium and serum and urine osmolarity were normalized. For vasculitis, the patient was treated with pulse steroid and cyclophosphamide.
Discussion
There should be high clinical suspicion of DI when a patient with systemic vasculitis presents with hypernatremia. MRI may be normal in the early stage of the CNS involvement; however, low serum copeptin and an increase in the urine osmolarity after desmopressin are key for diagnosis.