Abstract: TH-PO370
Gitelman Syndrome-Related Hypokalemic Nephropathy
Session Information
- Sodium, Potassium, and Volume Disorders: Clinical
October 24, 2024 | 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
- Pournazari, Kamyar, University of Maryland School of Medicine, Baltimore, Maryland, United States
- Browne, Maria Creciun, University of Maryland School of Medicine, Baltimore, Maryland, United States
- Seliger, Stephen L., University of Maryland School of Medicine, Baltimore, Maryland, United States
- Ejaz, Abutaleb Ahsan, University of Maryland School of Medicine, Baltimore, Maryland, United States
Introduction
Gitelman syndrome (GS) is a rare, inherited renal tubular disorder, usually considered a benign tubulopathy wherein progressive CKD is not a common feature. We present a 56-year-old WF with progressive decline in eGFR related to suspected Gitelman syndrome-associated hypokalemia.
Case Description
PMH of bipolar disorder, presented with asymptomatic, persistent hypokalemia and incidental CT finding of bilateral single kidney stone ~3mm. Current medications include bupropion HCL, Topiramate, diazepam and levothyroxine. Patient declined all K supplementation for years. Exam remarkable for thin body habitus, wt 112lbs, BP 102/59. Labs showed persistent hypokalemia and hyperbicarbonatemia over the past decade, SCR 1.66mg/dL, eGFR 36mL/min, CysC 1.68mg/dL, CysC-eGFR 37mL/min, Ca 10.1mg/dL, Mg 2.2mg/dL, UACR<7, UpH 5.5 and SG 1.021, PTH 34.1. eGFR declined from 76mL/min to 34mL/min over a 12-year period. Serum Aldo 9ng/dL, PRA 10.6ng/mL/hr. Gitelman syndrome was suspected and amiloride started, while 24hr urine studies were pending. (Figure 1)
Discussion
Hypokalemia is associated with interstitial fibrosis related to intrarenal vasoconstriction, increased RAS activation and inflammation, leading to tubular atrophy and dropout. Clinically, our patient had intact urine concentration and acidifying capacity. Reungjui et al have proposed another mechanism that involves decreased renal angiogenesis. Accordingly, macrophage-associated cytokines (IL-1β, IL-6, TNF-α) inhibit VEGF expression that causes progressive capillary loss, reduced EC proliferation and decline in GFR. The decade long direct correlation of persistent hypokalemia and progressive loss of eGFR in our patient substantiates our suspicion of Gitelman syndrome-related hypokalemic nephropathy.
Ref: Reungjui S, Roncal CA, Sato W, Glushakova OY, Croker BP, Suga S, Ouyang X, Tungsanga K, Nakagawa T, Johnson RJ, Mu W. Hypokalemic nephropathy is associated with impaired angiogenesis. J Am Soc Nephrol. 2008; 19:125-134.