Diagnostic accuracy of postnatal ultrasound screening for urinary tract abnormalities

Abstract

The study was aimed at (1) the determination of the incidence of abnormalities of the urinary tract in newborn infants detected by postnatal ultrasound screening, and (2) the evaluation of the diagnostic accuracy of postnatal ultrasound screening for detecting surgical urinary tract abnormalities. The prospective study was of full-term neonates born in the University Hospital of Olomouc in 2005-2008 who underwent renal ultrasound screening after 72 h of life. Significant findings were recorded. Subsequent diagnostic and therapeutic procedures were recorded and evaluated in a group of children with detected renal pelvic dilatation (RPD). (1) A total of 6,088 newborn infants was examined. The absolute and relative RPD incidence rates (anteroposterior diameter, APD) were as follows: 5-7 mm, 146 (2.4%); 7-10 mm, 70 (1.15%); 10-15 mm, 13 (0.21%), and 15 mm or more, 5 (0.08%). Of those, 16 children were operated on for abnormalities of the urinary tract, of which nine (56%) had been detected by prenatal screening. Other findings: six cases of unilateral renal agenesis, four cases of multicystic renal dysplasia, four of renal dystopia, one of polycystic kidney disease and one of renal hypoplasia. (2) A group of 224 children with postnatally detected RPD was examined, of whom 40 (17.9%) underwent voiding cystourethrography and/or scintigraphy and 16 (7.1%) were treated surgically. The receiver operating characteristic curves were analyzed, and the areas under the curves were calculated. Postnatal renal ultrasound screening is probably a suitable test for detecting significant urinary tract abnormalities.

A study on postnatal evaluation and follow-up of infants with antenatally detected hydronephrosis

“…In Halek and colleagues study, a 7-mm renal pelvic diameter cutoff was considered ideal for detection of significant uropathy. 8 In present study, a cut off of antenatal RPD =9.5 had 92.7% sensitivity and 72.3 % specificity in predicting the need for surgical intervention. In Bouzada and colleagues study, renal pelvic diameter15 mm was foundout as cutoff for determining those infants requiring surgery.…”

Value of renal pelvic diameter and urinary tract dilation classification in the prediction of urinary tract anomaly

“…There is still no strictly defined protocols in practice, yet the suitability of suggested protocols may depend on the facilities of the centers. Several studies have analyzed the correlation of prenatal UTD severity and outcome, but few have evaluated the validity of postpartum initial US in grading the severity of UTD and outcome …”

Ultrasound screening in a neonatal unit

“…7 Abnormalities range from those that are incompatible with life, to clinically insignificant ones. 7 Diagnosis is important because early treatment of some conditions may prevent irreversible renal damage. The most common renal abnormality demonstrated on US is dilatation of the renal pelvis.…”

“…The most common renal abnormality demonstrated on US is dilatation of the renal pelvis. 7 Other abnormalities that can be demonstrated are: renal agenesis, multicystic dysplasia and polycystic kidneys, abnormal position of the kidney and horseshoe kidney.…”