Periprocedural antibiotics for urodynamic studies of pediatric neurogenic bladder, empiric or culture-guided? A retrospective cohort study.

INTRODUCTION: Urodynamic studies are fundamental in the care of children with neurogenic bladder. Children with neurogenic bladder who perform clean intermittent catheterization (CIC) are considered a high-risk group for infection after urodynamic studies. Current guidelines are not uniform regarding the duration, type, the need of prophylactic antibiotic treatment or performance of urine culture before urodynamic studies.

OBJECTIVE: To assess whether antibiotic prophylactic therapy before urodynamic studies should be empiric or culture-guided in children with neurogenic bladder who perform CIC.

STUDY DESIGN: Urine samples were collected from children with neurogenic bladder who require CIC before undergoing a urodynamic study. Urine cultures were collected via sterile urethral catheterization one week before urodynamic studies between 2010 and 2018. Children with signs of urinary tract infection (UTI) or children with bladder augmentation were excluded. Resistance to commonly prescribed periprocedural antibiotic treatments was documented. The probability of antibiotic resistance according to sex, vesicoureteral reflux (VUR) status, consumption of prophylactic antibiotics, and self/caregiver performed CIC was determined by a χ2-test.

RESULTS: A total of 278 urine cultures were collected from 185 children with neurogenic bladder. The median age was 8 years (IQR 5-12). The most common etiology for neurogenic bladder was spinal dysraphism (n = 146, 77%). Bacterial growth was detected in 216 (78%) cultures, and the most commonly detected bacterial species was Escherichia. coli (n = 155, 72%). Thirty-six (19%) children had VUR, and 14 of them received continuous prophylactic antibiotics. The probability of resistance to oral antibiotics was amoxicillin (22%), cephalexin (21%), cefuroxime (14%), ciprofloxacin (10%), nitrofurantoin (21%), and sulfamethoxazole/trimethoprim (SMX/TMP) (23%) (See "summary table") No significant differences were found by χ2-test in the probability of resistance to antibiotics according to sex, VUR status, continuous antibiotic prophylaxis or self/caregiver performed CIC.

DISCUSSION: The study reveals high resistance level to commonly prescribed oral antibiotic treatments (20-30%). Several studies have challenged the need of routine urine cultures before urodynamic studies due to low risk of post-procedural infection. However, it should be mentioned that not all the patients participating in those studies were with neurogenic bladder or routinely performed CIC. Hence, in this specific group of children, routine urine cultures should not be abandoned. The limitations of the study are: Single-center, retrospective study with no data availability regarding the development of UTI after the urodynamic studies.

CONCLUSIONS: Urine cultures of children with neurogenic bladder who require CIC demonstrate significant levels of resistance to commonly prescribed oral antibiotics. These findings support culture-guided periprocedural antibiotic prophylaxis.