Oral steroids for reducing kidney scarring in young children with febrile urinary tract infections: the contribution of Bayesian analysis to a randomized trial not reaching its intended sample size

Background This study aimed to evaluate the effect of oral dexamethasone in reducing kidney scars in infants with a first febrile urinary tract infection (UTI). Methods Children aged between 2 and 24 months with their first presumed UTI, at high risk for kidney scarring based on procalcitonin levels (≥1 ng/mL), were randomly assigned to receive dexamethasone in addition to routine care or routine care only. Kidney scars were identified by kidney scan at 6 months after initial UTI. Projections of enrollment and follow-up completion showed that the intended sample size could not be reached before funding and time to complete the study ran out. An amendment to the protocol was approved to conduct a Bayesian analysis. Results We randomized 48 children, of whom 42 had a UTI and 18 had outcome kidney scans (instead of 128 planned). Kidney scars were found in 0/7 and 2/11 patients in the treatment and control groups respectively. The probability that dexamethasone could prevent kidney scarring was 99% in the setting of an informative prior probability distribution (which fully incorporated in the final inference the information on treatment effect provided by previous studies) and 98% in the low-informative scenario (which discounted the prior literature information by 50%). The probabilities that dexamethasone could reduce kidney scar formation by up to 20% were 61% and 53% in the informative and low-informative scenario, respectively. Conclusions Dexamethasone is highly likely to reduce kidney scarring, with a more than 50% probability to reduce kidney scars by up to 20%. Trial registration number EudraCT number: 2013-000388-10; registered in 2013 (prospectively registered) Graphical Abstract

Clinical Course of Children and Adolescents with Primary Vesicoureteral Reflux: A retrospective study of 958 patients

Introduction. Vesicoureteral reflux (VUR) is the most common pediatric urologic abnormality and since it can predispose to urinary tract infection and resultant kidney scar it is an important issue in pediatric nephrourology. Methods. A retrospective chart review and follow-up of 958 patients with primary VUR was performed in the Children’s Medical Center, Tehran, Iran. Children with primary vesicoureteral reflux were included in the study and these parameters were studied: age, sex, clinical presentation, VUR grade, sonographic findings, DMSA changes, treatment modality (medical, surgical or endoscopic) and response to treatment, hypertension (presence/absence), urinary tract infection recurrence and development of new kidney scars in patients under medical treatment. Results. VUR was more prevalent in girls. Sonography was unable to detect VUR in many cases. Presence of renal scars was strongly associated with degree of reflux. Medical management was effective in a substantial percentage of patients and they experienced full resolution of reflux. This was especially true for lower degrees of VUR. 17.6% of patients developed new kidney scars on followup which was associated with higher degrees of VUR. Hypertension and breakthrough urinary tract infection was an uncommon finding in our patients. Conclusion. Medical management, which means using prophylactic antibiotics for prevention of urinary tract infection, is effective in many cases of VUR especially in cases with lower degrees of VUR. Surgical and endoscopic procedures must be reserved for patients with higher degrees of VUR unresponsive to conservative management or in whom new scars may develop.