Factors Predicting Renal Function Outcome after Augmentation Cystoplasty
PURPOSE Children with chronic renal insufficiency and neuropathic bladder resistant to medical management may require lower urinary tract reconstruction before renal transplantation. A low pressure urinary reservoir optimizes the chance of graft survival and may slow native kidney death. We evaluated whether the renal deterioration rate is affected by augmentation cystoplasty. MATERIALS AND METHODS We performed a retrospective cohort study in children who presented to our institution with chronic renal insufficiency and neuropathic bladders from 2005 to 2009. Chronic renal insufficiency was defined as a glomerular filtration rate of less than 60 ml per minute. As a surrogate for renal function change, we used the inverse creatinine trend with respect to time to determine the progression rate of renal insufficiency before and after augmentation. RESULTS A total of 11 patients with a mean glomerular filtration rate of 34 ml per minute per 1.73 m(2), mean bladder capacity 168 ml and mean compliance 3.5 ml/cm H(2)O met study inclusion criteria. Bladder augmentation or replacement was done at a mean age of 9.7 years with a resultant mean capacity of 486 ml and compliance of 14.7 ml/cm H(2)O. Mean followup was 4 years before and 1.9 years after augmentation. There was no statistically significant difference between the preoperative and postoperative slopes of inverse creatinine in 8 of 11 patients (73%). Two of the 3 patients (18%) with different preoperative and postoperative slopes had improving renal function after surgery. There was no statistically significant difference in slopes across all patients. CONCLUSIONS In our series bladder augmentation did not appear to hasten progression to end stage renal disease in patients with severe chronic renal insufficiency and neuropathic bladder.