Gitelman Syndrome Overview What? • Inherited (AR) hypokalemic salt-losing tubulopathies affecting the thiazide-sensitive sodium chloride cotransporter • Gitelman's syndrome - Mutation in the SLC12A3 gene • SLC12A3 gene - Encodes thiazide-sensitive sodium chloride cotransporter (NCCT) present in the apical membrane of cells on the distal convoluted tubule (DCT) Clinical Presentation: • Phenotypically similar to that of patients with thiazide diuretic abuse • Salt craving • Fatigue • Muscle weakness, dizziness • Nocturia • Palpitations When to suspect? • Family history of hypokalemia • Unexplained hypokalemia, mild hypomagnesemia • Metabolic alkalosis • Normal or low blood pressure Labs: • Hypokalemia (renal potassium wasting) • Hypomagnesemia • Hypochloremic metabolic alkalosis • Hypocalciuria (spot urine, calcium-creatinine ratio 0.5%) Differential Dx? • Surreptitious vomiting • Surreptitious diuretic use • Autoimmune disease (Sjögren syndrome, Renal tubular acidosis (RTA)) • Refeeding syndrome • Bartter syndrome • Pseudo Bartter-Gitelman syndrome • Laxative abuse • Licorice • Congenital chloride diarrhea Potential Complications: • Ventricular tachycardia • Seizures • Rhabdomyolysis Treatment - Supplement: • Potassium • Magnesium #Gitelman #Syndrome #diagnosis #nephrology #management #pathophysiology #Hypokalemia
