Gitelman syndrome: A case report

BACKGROUND: Gitelman syndrome (GS) is an autosomal recessive salt-losing renal tubulopathy arising from mutations in the thiazide-sensitive Na-Cl cotransporter gene. Due to its low incidence and lack of awareness, GS can be easily misdiagnosed or missed in diagnosis. CASE SUMMARY: A 24-year-old male presented with > 4 years of repeated limb weakness without any treatment. The previous day, the patient was bitten by ants and showed weakness of the lower limbs. The patient had hypokalemia (1.66-2.83 mmol/L), hypomagnesemia (0.4 mmol/L), hypocalciuria (1.51-2.46 mmol/d), metabolic alkalosis (7.47-7.54), normal blood pressure, and increased activity of aldosterone and plasma renin activity (PRA) (PRA 6.4 and 16.45 ng/mL/h and aldosterone 330.64 and 756.82 pg/mL in the supine and upright position, respectively). In addition, SLCI2A3 gene mutation with GS was diagnosed. Oral and intravenous supplementation with potassium and magnesium was initiated. Serum magnesium returned to 0.48 mmol/L and serum potassium returned to 3.08 mmol/L, alleviating the patient’s fatigue symptoms. CONCLUSION: GS should be considered in patients with hypokalemia complicated with hypomagnesemia. Genetic testing is essential to confirm the diagnosis.