Abstract: PO1159
Multi-Electrolyte Storm Associated with Non-Exocrine Manifestations of Sjögren Syndrome
Session Information
- Salt, Potassium, and Water Balance: Clinical
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Fluid, Electrolyte, and Acid-Base Disorders
- 902 Fluid, Electrolyte, and Acid-Base Disorders: Clinical
Authors
- Viswanathan, Sahityan, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Sambandam, Kamalanathan K., The University of Texas Southwestern Medical Center, Dallas, Texas, United States
Introduction
Kidneys are one of the more commonly affected non-exocrine glands by Sjögren’s syndrome. Renal involvement includes glomerulonephritis, interstitial nephritis, or both. Chronic TIN is the most common renal manifestation in Sjögren’s syndrome. Clinical manifestations of TIN present as abnormalities of tubular function such as Fanconi syndrome, Distal RTA and Nephrogenic DI.
Case Description
26 y/o Hispanic female with no known past medical history present with nausea and vomiting at 21 weeks gestation of her second pregnancy. Workup was significant for elevated creatinine with proteinuria and pyuria, normal anion gap metabolic acidosis, hypokalemia, and hyphosphatemia. Urine studies revealed an inappropriately alkaline urine with impaired renal reclamation of potassium and phosphorous. Serological workup was significant for positive ANA, SSA, and SSB antibodies. Kidney biopsy revealed acute tubulointerstitial nephritis. The patient was started on an IV steroid course with oral taper and hydroxychloroquine with improvement in Cr from 2.2 to 1.2 mg/dL. with a potassium, phosphate and sodium bicarbonate supplementation regimen.
Discussion
Sjögren’s syndrome is typically associated with lymphocytic infiltration of exocrine glands. However, this can also affect the kidneys causing tubulointerstitial nephritis and defects in tubular function initiating a cascade of electrolyte abnormalities. Understanding the renal physiology behind the observed electrolyte abnormalities is important to optimize our treatment regimen. While the management of a distal RTA that has been well described in Sjögrens syndrome typically involves judicious potassium and alkali supplementation, this case highlights the worsening potassium wasting and phosphorous wasting which also needs to be addressed with a concomitant proximal tubulopathy. We propose that this set of features can best be explained by dysfunctional carbonic anhydrase, a cause of the extremely rare type III RTA. We use this case presentation to highlight the spectrum of renal manifestations of Sjogren’s syndrome and their treatment principles.