Distal renal tubular acidosis as a rare complication of vesicoureteral reflux in children: a case report and literature review

Distal renal tubular acidosis (dRTA) is a clinical picture of hyperchloremic hypokalemic metabolic acidosis with a normal anion gap. It can be caused by a variety of conditions including obstructive uropathy such as vesicoureteral reflux (VUR). We report a rare case of dRTA secondary to VUR in a 4-year-old girl with a history of meningomyelocele, neurogenic bladder and recurrent urinary tract infections. She was admitted to the hospital with complaints of polydipsia, polyuria, and inability to gain weight for the last 1 year. She was on prophylactic antibiotic treatment with clean intermittent catheterization and anticholinergic drug. She had a history of subureteral injection of various agents and botulin toxin injection into the bladder. Her voiding cystourethrogram revealed grade 5 VUR in the left kidney, tortuosity in the left ureter, and the bladder had a dome-like appearance and was trabeculated. When all laboratory values of the patient since birth were examined, it was observed that urine pH was high despite hypokalemic hyperchloremic metabolic acidosis for the last year; these abnormalities became more severe in the last few months. In conclusion, the development of hypokalemia and nephrolithiasis/nephrocalcinosis along with metabolic acidosis in a patient diagnosed with VUR should be considered as an indicator of impaired tubular functions. Also, the possibility of an underlying VUR in the presence of recurrent urinary tract infection in a patient diagnosed with dRTA should not be ignored.