Transient Pseudohypoaldosteronism Secondary to Group B Streptococcus Pyelonephritis

Secondary pseudohypoaldosteronism is a condition characterized by aldosterone resistance in renal tubules. It is highly associated with urinary tract infection and urinary tract malformations. Only a few cases of pseudohypoaldosteronism secondary to group B Streptococcus pyelonephritis have been reported to date. A four-month-old boy developed poor sucking and weight loss, and his laboratory test results revealed hyponatremia, hyperkalemia, renal dysfunction, high anion gap metabolic acidosis, pyuria, and hydronephrosis. Laboratory tests including urinalysis confirmed the diagnosis of pseudohypoaldosteronism secondary to group B Streptococcus. He was treated with intravenous normal saline and antimicrobial therapy. Electrolyte disorders were addressed and he was discharged on the 10th day of hospitalization without any sequelae. Voiding cystourethrography performed after discharge showed bilateral grade 5 vesicoureteral reflux and intrarenal reflux in the right kidney. Transient pseudohypoaldosteronism is an important consideration in the differential diagnosis in infants with hyponatremia and hyperkalemia. A thorough evaluation for urinary tract malformations should be performed, including early abdominal ultrasonography and systemic management.