Direct and Indirect Radionuclide Cystography: Can They Predict the Absence of Infectious Complications in Vesicoureteral Reflux?

Introduction: Radionuclide cystography is a commonly used examination technique for managing vesicoureteral reflux (VUR). Our aim was to compare direct radionuclide cystography (DRC) with indirect radionuclide cystography (IRC) and study the evolution of patients who tested negative for VUR using either test.

Material and methods: A retrospective observational study was conducted by collecting all radionuclide cystography scans performed in our centre to detect VUR among paediatric patients over 5 years old. Subgroup analysis was also performed on DRC or IRC scans negative for VUR to study the occurrence of infectious complications in these patients during follow-up.

Results: A total of 62 DRC and 46 IRC scans were collected from the patients with an average age of 65.4 ± 52.6 months at the time of the exam. Among the 62 DRC and 46 IRC cases, 38 and 34 tested negative for reflux, respectively. The IRC group showed a higher percentage of reinfection (62.5% vs. 37.5% of DRC, p = 0.16) and a greater number of visits to the emergency room due to infection (60% vs. 40% of DRC, p = 0.26) but a lower percentage of readmissions due to infection (33.3% vs. 66.7% of DRC, p = 0.47) than the DRC group. Among the remaining studied variables, only constipation was associated with an increased risk of admission due to infection (odds ratio (OR) = 29.62, p = 0.03) in these patients.

Conclusions: Patients with IRC negative for VUR had a higher percentage of reinfections during follow-up than those with DRC negative for VUR, although the difference did not reach statistical significance. Furthermore, paediatric patients with a negative radionuclide cystography for VUR and who suffer from constipation have an increased risk of admission for infectious complications.