The study shall be undertaken at the Department of Pediatrics, JIPMER from Jan 2025 for a period of 2 years after acquiring the Institutional Ethics Committee (IEC) clearance and CTRI registration prior to enrolment of the first patient. This study shall include patients aged 3 months to 18 years undergoing VCUG. When these patients come to the hospital for VCUG (absence of signs/symptoms of UTI at the time of presentation and a negative urine culture within the preceding 2 weeks are mandatory to undertake the test), they will be approached for possible enrollment into the trial. Written informed consent will be taken from the parents of the study participants (and assent from children 8 years or older) and the study will be conducted in accordance with the Declaration of Helsinki.  

Once the patients are enrolled, they will be randomly allocated to group A or group B based on which they will either receive antibiotic or placebo. The children already on antibiotic prophylaxis will be stratified and then allocated to group A  or group B. The subjects will receive one dose of the drug (antibiotic/placebo) 30-60 minutes prior to the procedure and the second dose 4-8 hours after the procedure. VCUG will be performed under strict aseptic precautions as per standard protocols being followed in the radiology department of the institute. On the evening of the procedure, a telephonic call will be made to all the enrolled participants to enquire about development of any signs/ symptoms of UTI and if the child has taken the evening dose of the medicine (antibiotic/ placebo).

Subsequently, all enrolled patients will be followed up for development of UTI over the next 7 days (considering the day of VCUG as day 1). Urine sample of those patients who present with signs and symptoms of urinary tract infection within 7 days post-VCUG will be collected and sent for urine routine and culture. They will be admitted in the Pediatrics ward and administered parenteral antibiotics as per ISPN 2023 guidelines.

If patients do not develop signs/symptoms of UTI, they will undergo urine routine and culture testing to look for prevalence of asymptomatic bacteriuria and identify antibiotic sensitivity pattern.

Ad per current practice, patients report to the pediatric nephrology clinic 2-7 days after VCUG to interpret the findings of VCUG and make further management decisions. If patients do not report to the pediatric nephrology clinic by day 5 post VCUG, a telephonic reminder will be sent to them apart from enquiring about the signs and symptoms of UTI that might have developed post VCUG.