The conundrum of high-grade hydronephrosis with non-obstructive drainage on diuretic renography.

BACKGROUND: Patients with high grade hydronephrosis (HN) and non-obstructive drainage on mercaptoacetyltriglycine (MAG-3) diuretic renography (renal scans) can pose a dilemma for clinicians. Some patients may progress and require pyeloplasty; however, more clarity is needed on outcomes among these patients. OBJECTIVE: Our primary objective was to predict which patients with high-grade HN and non-obstructive renal scan, (defined as T ½ time <20 min) would experience resolution of HN. Our secondary objective was to determine predictors for surgical intervention. STUDY DESIGN: Patients with prenatally detected HN were prospectively enrolled from 7 centers from 2007 to 2022. Included patients had a renal scan with T ½<20 min and Society for Fetal Urology (SFU) grade 3 or 4 at last ultrasound (RBUS) prior to renal scan. Primary outcome was resolution of HN defined as SFU grade 1 and anterior posterior diameter of the renal pelvis (APD) < 10 mm on follow-up RBUS. Secondary outcome was pyeloplasty, comparing patients undergoing pyeloplasty with patients followed with serial imaging without resolution. Multivariable logistic regression was used for analysis. RESULTS: Of the total 2228 patients, 1311 had isolated HN, 338 patients had a renal scan and 129 met inclusion criteria. Median age at renal scan was 3.1 months, 77% were male and median follow-up was 35 months (IQR 20-49). We found that 22% (29/129) resolved, 42% of patients had pyeloplasty (54/129) and 36% had persistent HN that required follow-up (46/129). Univariate predictors of resolution were age≥3 months at time of renal scan (p = 0.05), T ½ time≤5 min (p = 0.09), SFU grade 3 (p = 0.0009), and APD<20 mm (p = 0.005). Upon multivariable analysis, SFU grade 3 (OR = 4.14, 95% CI: 1.30-13.4, p = 0.02) and APD<20 mm (OR = 6.62, 95% CI: 1.41-31.0, p = 0.02) were significant predictors of resolution. In the analysis of decision for pyeloplasty, SFU grade 4 (OR = 2.40, 95% CI: 1.01-5.71, p = 0.04) and T ½ time on subsequent renal scan of ≥20 min (OR = 5.14, 95% CI: 1.54-17.1, p = 0.008) were the significant predictors. CONCLUSIONS: Patients with high grade HN and reassuring renal scan can pose a significant challenge to clinical management. Our results help identify a specific candidate for observation with little risk for progression: the patient with SFU grade 3, APD under 20 mm, T ½ of 5 min or less who was 3 months or older at the time of renal scan. However, many patients may progress to surgery or do not fully resolve and require continued follow-up.

Continuous antibiotic prophylaxis in isolated prenatal hydronephrosis.

BACKGROUND: Prenatal hydronephrosis (PNH) is one of the most common congenital anomalies and can increase the risk of developing a urinary tract infection (UTI) in the first two years of life. Continuous antibiotic prophylaxis (CAP) has been recommended empirically to prevent UTI in children with PNH, but its use has been controversial. OBJECTIVE: We describe the incidence of UTI in children with isolated PNH of the renal pelvis without ureteral dilation. Our objective was to compare patients receiving and not receiving CAP and determine whether CAP is beneficial at preventing UTI in children with isolated PNH. STUDY DESIGN: Children with confirmed PNH were enrolled between 2008 and 2020 into the Society for Fetal Urology Hydronephrosis Registry. Children with isolated dilation of the renal pelvis without ureteral or bladder abnormality were included. The primary outcome was development of a UTI, comparing patients who were prescribed and not prescribed CAP. RESULTS: In this cohort of 801 children, 76% were male, and 35% had high grade hydronephrosis (SFU grades 3-4). CAP was prescribed in 34% of children. The UTI rate among all children with isolated PNH was 4.2%. Independent predictors of UTI were female sex (HR = 13, 95% CI: 3.8-40, p = 0.0001), intact prepuce (HR = 5.1, 95% CI: 1.4-18, p = 0.01) and high grade hydronephrosis (HR = 2.0, 95% CI: 0.99-4.0, p = 0.05; Table) on multivariable analysis. For patients on CAP, the UTI rate was 4.0% compared to 4.3% without CAP (p = 0.76). The risk of UTI during follow-up was not significantly different between patients who received CAP and patients who were not exposed to CAP; adjusting for sex, circumcision status and hydronephrosis grade (HR = 0.72, 95% CI: 0.34-1.5, p = 0.38). In sub-group analysis of patients at higher risk of UTI (uncircumcised males, females and high grade hydronephrosis), CAP use was not associated with a statistically significant reduction in UTI. CONCLUSIONS: The overall UTI rate in children with isolated PNH is very low at 4.2%. In the overall population of patients with isolated PNH, CAP was not associated with reduction in UTI risk, although the limitations in our study make characterizing CAP effectiveness difficult. Clinicians should consider risk factors prior to placing all patients with isolated PNH on CAP.

Risk of urinary tract infection in patients with hydroureter: An analysis from the Society of Fetal Urology Prenatal Hydronephrosis Registry.

BACKGROUND: Prenatal hydronephrosis is one of the most common anomalies detected on prenatal ultrasonography. Patients with prenatal hydronephrosis and ureteral dilation are at increased risk of urinary tract infection (UTI) and continuous antibiotic prophylaxis (CAP) is recommended. However, current guidelines do not define the minimum ureteral diameter that would be considered a dilated ureter in these patients. OBJECTIVE: We evaluate the definition of clinically relevant hydroureter, its association with UTI, and the impact of CAP. STUDY DESIGN: Patients with prenatal hydronephrosis from seven centers were enrolled into the Society for Fetal Urology Prenatal Hydronephrosis Registry from 2008 to 2020. Patients with ureteral measurement on ultrasound were included. Patients with ureterocele, ectopic ureter, neurogenic bladder, posterior urethral valves, horseshoe or solitary kidney, known ureteropelvic junction obstruction, or follow-up less than one month were excluded. Primary outcome was UTI. Analyses were performed using Cox regression. RESULTS: Of the 1406 patients enrolled in the registry, 237 were included. Seventy-six percent were male, ureteral diameter ranged from 1 to 34 mm, and median follow-up was 2.2 years. Patients with ureters 7 mm or greater had nearly three times the risk of UTI adjusting for sex, circumcision status, antibiotic prophylaxis and hydronephrosis grade (HR = 2.7, 95% CI: 1.1-6.5, p = 0.03; Figure). In patients who underwent voiding cystourethrogram (VCUG; 200/237), ureteral dilation of 7 mm or more identified patients at increased UTI risk controlling for sex, circumcision status, vesicoureteral reflux and hydronephrosis grade (HR = 2.3, 95% CI: 0.97-5.6, p = 0.06). CAP was significantly protective against UTI (HR = 0.50 (95% CI: 0.28-0.87), p = 0.01). Among patients who underwent VCUG and did not have vesicoureteral reflux, ureteral dilation 7 mm or greater corresponded with higher UTI risk compared to ureteral diameter less than 7 mm on multivariable analysis (HR = 4.6, 95% CI: 1.1-19.5, p = 0.04). CONCLUSIONS: This is the first prospectively collected, multicenter study to demonstrate that hydroureter 7 mm or greater identifies a high-risk group for UTI who benefit from antibiotic prophylaxis. In contrast, patients with prenatal hydronephrosis and non-refluxing hydroureter less than 7 mm may be managed more conservatively.

Current Evidence Related to Intermittent Catheterization: A Scoping Review.

PURPOSE: The purpose was to summarize evidence related to adherence to intermittent catheterization (IC), complication rates, satisfaction with IC, and its effect on health-related quality of life. PROBLEM: Intermittent catheterization is frequently used to manage lower urinary tract dysfunctions including urinary retention and urinary incontinence, but research suggests that care for patients using IC may not always be based on evidence. METHODS: Scoping review. SEARCH STRATEGY: We searched the PubMed, EMBASE, CINAHL databases, and the Cochrane Database for Systematic Reviews to identify studies published between January 2009 and March 2019. Seventy studies met inclusion criteria and were evaluated for adherence, complication rates, satisfaction, and health-related quality in adults and children using IC for bladder management. FINDINGS: Recent research was variable in both quantity and quality. The evidence suggests that (1) most patients can successfully master IC and that functional status is likely the most important predictor of success; (2) adherence to IC probably decreases over time; (3) urinary tract infections (UTIs) are the most common complication of IC and that prophylactic antibiotic therapy may reduce the risk of recurrent UTIs; (4) urinary incontinence is also a common complication; and (5) other complications such as urethral strictures, bladder stones, hematuria, and urethral false passage do occur but are less prevalent than UTIs and incontinence between catheterizations. Our review also revealed multiple gaps in the evidence to support care for patients using IC. CONCLUSIONS: Research priorities include a need for prospective studies of the epidemiology and risk factors for IC-related complications, along with intervention studies to determine how to improve outcomes for patients using IC to manage bladder function.