Outcome and management of isolated severe renal pelvis dilatation detected at postnatal screening

The Diagnostic Efficacy of and Requirement for Postnatal Ultrasonography Screening for Congenital Anomalies of the Kidney and Urinary Tract

BACKGROUND

We aimed to investigate the efficacy of postnatal ultrasonography in detecting congenital anomalies of the kidneys and urinary tract in term infants without prenatal history of congenital anomalies of the kidneys and urinary tract.

METHODS

In this retrospective cohort study, we reviewed the records of term infants between six weeks and three months of age who underwent urinary tract ultrasonography during routine pediatric care.

RESULTS

Congenital anomalies of the kidneys and urinary tract were detected on prenatal ultrasonography in 75 of the 2620 patients included in the study. Congenital anomalies of the kidneys and urinary tract were detected via postnatal USG in 46 (1.8%) of 2554 patients without anomalies on prenatal USG screening. The most common anomaly was hydronephrosis (69.6%). Thirty-two cases of hydronephrosis, three cases of renal agenesis, four cases of horseshoe kidney, one case of MCDK, and two cases of duplex systems which were not detected on prenatal USG were detected on postnatal USG. On the other hand, 29 (1.1%) cases with mild or moderate hydronephrosis on prenatal ultrasonography did not have hydronephrosis on postnatal ultrasonography.

CONCLUSIONS

In our study, approximately one-third of the cases of hydronephrosis, unilateral renal agenesis, duplex systems, horseshoe kidney, and ectopic kidney were not detected in prenatal ultrasonography screening. Therefore, we believe that in addition to prenatal ultrasonography screening, postnatal ultrasonography screening of all children for urinary tract anomalies would be beneficial.

Early detection of congenital anomalies of the kidney and urinary tract: cross-sectional results of a community-based screening and referral study in China

OBJECTIVE

To establish an effective screening model of congenital anomalies of the kidney and urinary tract (CAKUT) using ultrasound among neonates in Shanghai, China.

DESIGN

Cross-sectional study.

SETTING

A three-level screening model for CAKUT in neonates based on the child healthcare system was established since 2010 in Minhang District, Shanghai, China.

PARTICIPANTS

During 2010-2015, neonates with criteria such as preterm, low birth weight and so on were eligible to participate in the study. Cases with renal pelvis dilatation (RPD) and other abnormal renal findings were managed based on presumed strategies.

MAIN OUTCOME MEASURES

The proportion of RPD and other renal and urinary tract anomalies; number of diagnosed CAKUT under integrated management, especially obstructive uropathy. The anterior-posterior renal pelvic diameter (APRPD) cut-off points for likelihood of obstructive uropathy and need for surgery.

RESULTS

A total of 8827 infants were consecutively screened. Absolute and relative rates of different degrees of RPD classified by APRPD were: mild (5-9.9 mm), 984 (11.1%); moderate (10-14.9 mm), 176 (2.0%); severe (≥15 mm), 20 (0.2%). Of 639 followed cases with RPD, 11 were diagnosed as obstructive uropathies. Of these, nine patients underwent surgery, at median age 2 months. A total 85.4% of mild, 62.5% of moderate and 30.0% of severe RPD cases resolved spontaneously. Other renal and urinary morphological abnormalities were diagnosed in 15 (0.2%) patients. The APRPD cut-off points for significant obstructive uropathy and need for surgery were 9.7 mm and 13.5 mm, respectively.

CONCLUSIONS

This three-level screening model is an effective and feasible strategy for early detection and intervention of CAKUT in the early postnatal period, especially for patients with high-grade RPD and other renal and urinary malformations. This strategy could be useful in China and other developing areas with limited medical resources.

Clinical importance of pyelocalyceal dilation diagnosed by postnatal ultrasonographic screening of the urinary tract

Background

Ultrasonographic (US) screening of the urinary tract (UT) in infants was used to determine if there is a connection between the frequency of pyelocaliceal dilation (PCD) in asymptomatic infants with normal antenatal US screening and occurrence of congenital anomalies of kidney and urinary tract (CAKUT) and urinary tract infections (UTI).

Material/Methods

US screening of the UT was performed on 1000 healthy infants, 7 days to 6 months old. Two subgroups of kidneys were described: subgroup 1 contained kidneys with anterior posterior pelvic diameter (APPD) of 5–9.9 mm, and subgroup 2 with APPD over 10 mm. US examinations and methods for detection of UTI and CAKUT were used.

Results

PCD was found in 74 infants (7.4%): 1.9% of infants had CAKUT, and 8.4% had UTI. In subgroup 1, CAKUT was found in 4 (6.3%) and UTI in 9 (14.3%) infants. In subgroup 2, CAKUT was found in 6 (54.5%), and UTI in 4 (36.4%) infants.

Conclusions

Mild PCD significantly increases the risk for CAKUT but not for UTI. Moderate to severe PCD significantly increases risk for both CAKUT and UTI. The postnatal US screening of UT is recommended for improved detection of PCD and associated CAKUT. Indirectly, postnatal US screening of UT can help in detecting people at risk for UTI in the first year of life, and therefore help prevent possible kidney damage.

Early risk factors for neonatal mortality in CAKUT: analysis of 524 affected newborns

BACKGROUND

Congenital abnormalities of the kidney and urinary tract (CAKUT) are significant causes of morbidity. The aim of the study was to determine predictive factors of mortality in newborns with CAKUT.

METHODS

All 29,653 consecutive newborns hospitalized in a tertiary neonatal unit between 1996 and 2006 were evaluated. The main outcome was neonatal mortality. The variables analyzed as risk factors were maternal age, first pregnancy, low birth weight (LBW), prematurity, oligohydramnios, and CAKUT associated with other malformations (Associated CAKUT).

RESULTS

CAKUT was detected in 524 newborns, with an overall prevalence of 17.7 per 1,000 live births. A total of 325 (62%) cases were classified as urinary tract dilatation, 79 (15.1%) as renal cystic disease, and 120 (22.9%) as other subgroups. In the urinary tract dilatation subgroup, independent risk factors for early mortality were Associated CAKUT [odds ratio (OR) 20.7], prematurity (OR 4.5) LBW (OR 3.8), oligohydramnios (OR 3.0), and renal involvement (OR 3.0). In the renal cystic disease subgroup, two variables remained associated with neonatal mortality: LBW (OR 12.3) and Associated CAKUT (OR 21.4).

CONCLUSION

The presence of extrarenal anomalies was a strong predictor of poor outcome in a larger series of infants with CAKUT.

Evaluation and management of urinary tract infections in the neonate

PURPOSE OF REVIEW

The prevalence of urinary tract infections (UTIs) among full-term neonates has been reported to be up to 1.1%, increasing up to 7% among those with fever. UTI in neonates may be the first indicator of underlying abnormalities of kidneys and the urinary tract.

RECENT FINDINGS

Early recognition and therapy of UTI and detection of risk factors offer chances for applying strategies to avoid renal damage and recurrences. However, established diagnostic strategies and prophylactic concepts today are under debate. Currently, the main focus has been on renal changes as indicators for underlying risk factors like vesicoureteral reflux, attaching much importance to dimercaptosuccinyl acid scans. Serum and urine markers will probably allow more restrictive diagnostic imaging. Prenatal and postnatal ultrasound screenings provide additional opportunities for prophylactic measures.

SUMMARY

Main objectives in the management of neonatal UTIs are the prevention of acute infection-related complications and renal damage. Neonates and very young infants with suspicious pyelonephritis should obligatorily be treated with a combination of parenterally administered antibiotics. As far as possible, diagnostic imaging should be risk-oriented and restricted to noninvasive, nonstressful procedures. The strategies of antibacterial prophylaxis for the prevention of recurrent UTIs are changing. In infants at risk, its benefits have not yet been proven by evident data.