Evaluation of bone mineral density after ileocystoplasty in children with and without myelomeningocele

Abstract

We evaluated the bone mineral density (BMD) after ileal augmentation cystoplasty in a group of children with and without myelomeningocele. Between 1996 and 2003, eight patients with neurogenic bladder and seven patients with non-neurogenic bladder underwent augmentation ileocystoplasty. Preoperative and postoperative serum creatinine and electrolytes were measured. All patients underwent clinical evaluation, supine height measurement, blood gas analysis, and BMD measurement using a dual energy X-ray absorptiometry (DEXA) postoperatively. BMD was measured at L1-L4 and femoral neck, and compared to age- and sex-matched population. Follow-up time was calculated from the day of surgery to the day of DEXA performance. A total of eight boys and seven girls with the mean age of 10.2 +/- 4.1 years were evaluated with respect to BMD measurement. Mean age was 9.8 years in neurogenic group and 10.5 in non-neurogenic group. Mean follow-up was 728 and 616 days in neurogenic and non-neurogenic groups, respectively. There were no significant differences between ages, follow-up times, preoperative and postoperative creatinine levels, pH and bicarbonate values, and supine heights. Mean BMD at L1-L4 was 55.7% in neurogenic group and 83.8% in non-neurogenic group. There was a statistically significant difference between the two groups (P = 0.02). Mean BMD at femoral neck was 72% in neurogenic group and 86.2% in non-neurogenic group. The difference was also statistically significant (P = 0.028). After augmentation ileocystoplasty, the BMD in early postoperative period of patients with myelomeningocele is lower than the patients with non-neurogenic neurogenic bladder, which have the same clinical characteristics except the neurologic pathology. In the light of our findings and the reported literature data as well, we may claim that BMD decrease after augmentation ileocystoplasty depends more on the underlying neurologic pathology and its locomotor consequences rather than the enterocystoplasty itself.