Febrile urinary tract infection with grade IV reflux and a renal scar in an infant
A 3-month-old girl is admitted with a first febrile urinary tract infection (39.2 °C, Escherichia coli >10⁵ CFU/mL). Antenatal ultrasound had shown bilateral hydronephrosis, worse on the left (renal pelvis 15 mm), which resolved on a postnatal scan at 6 weeks. She is thriving, feeding well, and has normal creatinine. Examination shows a soft abdomen and no palpable bladder; she has hard stool in the left colon, and her mother reports straining and infrequent stools. VCUG demonstrates left grade IV vesicoureteric reflux with mild ureteric tortuosity and no bladder outlet obstruction. DMSA scan shows a focal cortical defect in the left upper pole. The parents are reluctant to consider surgery and ask whether antibiotics alone are enough.
1. What is your immediate and medium-term management plan, including the role of antibiotic prophylaxis?
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I would treat the acute febrile urinary tract infection with intravenous antibiotics until she is afebrile and clinically improving, then complete a 7–10-day oral course guided by culture. I would start continuous antibiotic prophylaxis-trimethoprim–sulfamethoxazole is acceptable at this age with normal renal function-while arranging follow-up. Prophylaxis reduces recurrent febrile urinary tract infections in high-grade reflux, although it does not prevent all scars.
The medium-term plan must address bladder and bowel dysfunction: treat constipation with adequate fluid, fibre, and a laxative such as polyethylene glycol, and encourage regular toileting. Constipation is a reversible cause of reflux persistence and infection. I would also counsel the parents that a DMSA scan performed during acute infection can overestimate scarring, so a repeat scan after 6 months is reasonable if the first was done early. The key judgement is that antibiotics alone are not a complete plan; bowel management and surveillance are equally important.
2. The parents ask whether surgery is necessary. How do you counsel them about endoscopic injection versus ureteric reimplantation?
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Grade IV reflux with a renal scar and a febrile urinary tract infection is a high-risk combination. Continued reflux carries a risk of further scarring and hypertension. However, surgery is not an emergency, and a trial of prophylaxis plus bowel management for 6–12 months is defensible if the parents understand the risks and attend follow-up.
If surgery is chosen, endoscopic subureteric injection is minimally invasive and day-case, with success around 50–70% for grade IV. Open or robotic ureteric reimplantation has success above 95% but requires an abdominal incision, a hospital stay, and a longer recovery. I would explain that injection may need repeat procedures, while reimplantation is more definitive. The choice depends on the family's tolerance of repeat procedures and the child's anatomy. Recurrent febrile infections or new scarring would push me toward reimplantation.
3. What follow-up would you arrange, and when would you repeat imaging?
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I would review her monthly for the first 6 months, then every 3–6 months, checking growth, blood pressure, and adherence to prophylaxis. Urine culture is indicated for any fever. I would repeat a DMSA scan after 6–12 months to assess new scarring, and an ultrasound to monitor renal growth and drainage. I would not repeat a VCUG routinely unless she has a recurrent febrile infection or the reflux management depends on it.
The judgement point is to avoid over-imaging while not missing new scars. If she remains infection-free and grows normally, conservative follow-up is appropriate. If she develops another febrile urinary tract infection despite prophylaxis and bowel management, I would escalate to surgery rather than continue observation indefinitely.