Resolution rate of isolated low-grade hydronephrosis diagnosed within the first year of life

Abstract

Objective Diagnosis of low-grade hydronephrosis often occurs prenatally, during evaluation after urinary tract infection (UTI), or imaging for non-urologic reasons within the first year of life. Its significance in terms of resolution, need for antibiotic prophylaxis, or progression to surgery remains uncertain. We hypothesized that isolated low-grade hydronephrosis in this population frequently resolves, UTIs are infrequent, and progression to surgical intervention is minimal. Patients and methods Children <12 months old diagnosed hydronephrosis (Society for Fetal Urology [SFU] grade 1 or 2) between January 2004 and December 2009 were identified by ICD9 code. Patients with other urological abnormalities were excluded. Stability of hydronephrosis, UTI (≥100,000 CFU/mL bacterial growth) or need for surgical intervention was noted. Results Of 1496 infants with hydronephrosis, 416 (623 renal units) met inclusion criteria. Of 398 renal units with grade 1 hydronephrosis, 385 (96.7%) resolved or remained stable. Only 13 (3.3%) worsened, of which one underwent ureteroneocystostomy. Of 225 renal units with grade 2 hydro-nephrosis, 222 (98.7%) resolved, improved or remained stable, three (1.3%) worsened, of which one required pyeloplasty. Only 0.7% of patients in the ambulatory setting had a febrile UTI. Conclusions Low-grade hydronephrosis diagnosed within the first year of life remains stable or improves in 97.4% of renal units. Given the low rate of recurrent UTI in the ambulatory setting, antibiotic prophylaxis has a limited role in management.

Natural course of isolated mild congenital hydronephrosis: A 2‐year prospective study at a single center in Japan

“…The rate of spontaneous resolution of mild CH in the current study is in agreement with that of previous retrospective studies (approximately 90%) . However, the prevalence of CH in the present patients was slightly higher than that of other previous reports, which showed 1–5% .…”

“…The rate of spontaneous resolution of mild CH in the current study is in agreement with that of previous retrospective studies (approximately 90%). 9,10,15 However, the prevalence of CH in the present patients was slightly higher than that of other previous reports, which showed 1-5%. [3][4][5]23 This finding could be because our facility is a tertiary medical institution that deals with many cases of high-risk pregnancy.…”

“…This prevented us from definitely confirming that CH was only due to UPJO. However, retrospective studies have shown that spontaneous resolution of mild CH occurs at an average of 1 year after birth . Therefore, we believe that the follow‐up period used in the present study was sufficient for analysis.…”

“…6,7 CH varies from a case with normal renal function to a case leading to end-stage renal failure, depending on the severity of obstruction. 3,8 Although many patients with CH due to partial obstruction of the ureteropelvic junction undergo spontaneous remission that requires no aggressive therapeutic intervention, 9,10 renal dysfunction progresses in some cases. 3,11 This then requires surgical intervention, such as pyeloplasty.…”

Bacterial Profile and Drug Susceptibility Pattern of Urinary Tract Infection in Infants and Children

“…However, the percentage of infection in infants is higher in studies of Seyed Reza Mirsoleymani et al [10] (67.3%) and Ramiro J Madden-Fuentes et al [11] (86.04%) and the percentage of infection in children is lower accounting for 32.7% and 13.95% respectively. The ratio of male:female is similar in almost 3 studies.…”