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

Abstract

BackgroundUltrasonographic (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/MethodsUS 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.ConclusionsMild 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.

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

“…For this purpose, the urinary system is screened prenatally, and cases with CAKUT are followed up with postnatal ultrasonography. However, it is known that some cases of CAKUT cannot be detected using prenatal USG due to technical and physiological reasons [9,13,21,22]. In the few studies investigating the prevalence of CACUT with postnatal USG, there was no standardized screening period; screening was performed over a wide time interval from three days to six months and a CACUT prevalence of 1.5% to 7.4% was reported [11][12][13][14][15].…”

“…In our study, thirty-two cases of hydronephrosis were detected via postnatal USG, as well as three cases of renal agenesis, four cases of horseshoe kidney, one case of MCDK, and two cases of duplex systems that could not be detected using prenatal USG. Drnasin et al [21] reported the prevalence of hydronephrosis as 7.4% in a postnatal study of 1000 healthy infants screened with prenatal USG and reported as "normal". Miyakita et al [11] reported that 39% of 92 cases of hydronephrosis were detected in the prenatal period.…”

“…Spontaneous resolution occurred in 65.4% of cases of hydronephrosis detected on prenatal USG, compared to 71.9% of cases detected only on postnatal USG. In studies examining cases detected in postnatal screening, Drnasin et al [21] reported a total spontaneous resolution rate of 79.2%, including 83.1% of mild cases and 33.3% of moderate-to-severe cases, while Hálek et al [13] reported 82.1%. In studies examining cases detected in the prenatal period, Barbosa et al [26] reported spontaneous resolution in 90% and 75% of mild and moderate hydronephrosis, respectively, while Coelho et al [27] reported spontaneous resolution in 97% and 78% of mild and moderate hydronephrosis, respectively.…”