Metabolic consequences and tubular function after augmentation cystoplasty in children with neurogenic bladder

Jei-Wen Chang; Hui-Hsin Yang; Tzu-Ching Lin; Fang-Cheng Kuo; Yu-Hua Fan; Hsin-Hung Chen; Ling-Yu Yang; Chin-Su Liu; Hsin-Lin Tsai

doi:10.1097/JCMA.0000000000001172

Metabolic consequences and tubular function after augmentation cystoplasty in children with neurogenic bladder

J Chin Med Assoc. 2024 Sep 20. doi: 10.1097/JCMA.0000000000001172. Online ahead of print.

Authors

Jei-Wen Chang^{1

2

3}, Hui-Hsin Yang^{2

4}, Tzu-Ching Lin^{1

2}, Fang-Cheng Kuo^{2

4}, Yu-Hua Fan^{2

5}, Hsin-Hung Chen^{2

6}, Ling-Yu Yang^{2

7}, Chin-Su Liu^{2

4}, Hsin-Lin Tsai^{2

4}

Affiliations

¹ Department of Pediatrics, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
² Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC.
³ Institute of Emergency and Critical Care Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC.
⁴ Division of Pediatric Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
⁵ Department of Urology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
⁶ Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei Taiwan, ROC.
⁷ Department of Medical Education, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.

PMID: 39808531
DOI: 10.1097/JCMA.0000000000001172

Abstract

Background: Many studies have reported the renal outcomes and metabolic consequences after augmentation cystoplasty (AC), however few studies have discussed changes in renal tubular function. The aim of this study was to determine the prevalence of metabolic disturbances, evaluate renal tubular function and 24-hour urine chemistry to evaluate the association between metabolic alterations and urolithiasis after AC.

Methods: We investigated serum biochemistry, blood gas, and 24-hour urinary metabolic profile of children who underwent AC between January 2000 and December 2020. The outcomes assessed included metabolic complications, tubular function and magnesium status. Associations between 24-hour urinary chemistries and urolithiasis formation were also analyzed.

Results: A total of 25 patients with a mean follow-up period of 13.8±5.7 years were enrolled. The mean age at AC was 7.5±4.4 years, and 22 and 3 patients underwent AC using the ileum and colon, respectively. There were no abnormalities in serum levels of sodium, potassium, chloride and calcium. One (4.0%) patient was diagnosed with hypomagnesemia (magnesium <1.7 mg/dL) resulting from renal loss. Six (24.0%) patients had increased urinary β2-microglobulin levels and normal serum levels. The ratio of the maximum rate of tubular phosphate reabsorption to the glomerular filtration rate was low in 3 (12.0%) patients. Four (16.0%) patients had normal serum magnesium levels but urinary magnesium excretion < 40 mg/day. Urolithiasis occurred in 11 patients (44.0%). The most common 24-hour urine metabolic abnormality was hypomagnesiuria (72.0%). None of the urinary metabolic parameters or daily protein intake were associated with urolithiasis.

Conclusion: AC for children is safe and does not have an obvious negative impact on metabolic profile, although a high prevalence of 24-hour urine magnesium excretion < 88 mg/1.73 m2 was noted. This study highlights the importance of longitudinal follow-up of renal tubular function and 24-hour urine metabolic profile, especially magnesium status.