Metabolic acidosis in a kidney transplantation who underwent bladder augmentation and both nephrectomy due to myelomeningocele

Abstract

Bladder augmentation using the gastrointestinal tract is an enlargement surgery designed to lower bladder pressure in patients with low bladder compliance. But, metabolic acidosis develops in some patients who have had bladder augmentation using the gastrointestinal tract due to the part of the intestine that absorbs urinary components including hydrogen ions and chlorides, and exchanges sodium for bicarbonate. We experienced a rare case of metabolic acidosis in a kidney transplantation who underwent bladder augmentation and both nephrectomy due to myelomeningocele. A 33-year-old male born with myelomeningocele and neurogenic bladder. He started hemodialysis due to severe hydronephrosis and recurrent cystitis. But inpatient treatment was repeated for recurrent cystitis undergoing clean intermittent self-catheterization. In the end, both nephrectomies were performed and bladder augmentation when he was 28 years old. A 20 cm distal ileal segment was isolated proximal to the ileo-cecal valve. The bladder dome was incised and ileo-bladder anastomosis was performed. He received a cadaveric donor kidney transplantation when he was 33 years old. His postoperative course was stable, but severe metabolic acidosis developed on postoperative day 15. At that time, the serum creatine 1.71 mg/dL and urine output was maintained at 3,000 cc/day. Arterial blood gas demonstrated hyperchloremic metabolic acidosis with pH 7.28, bicarbonate 14 mmol/L. Normal serum AG of 9 mEq/L and CRP (<0.5 mg/dL) may rule out the initial diagnosis of urosepsis, high urine AG of 22 mEq/L has a narrow differential diagnosis that include renal tubular acidosis (RTA). However, urine pH 7.0 and serum K of 4.6 mmol/L may rule out the RTA. We started intravenous sodium bicarbonate supplementation and the metabolic acidosis improved. On his most recent outpatient visit, he had no further metabolic acidosis without complications. In this report, we introduce a rare case with transient severe hyperchloremic metabolic acidosis in a kidney transplantation who underwent bladder augmentation using distal ileum.