Selection of infants who potentially have congenital anomalies of the kidney and urinary tract from a large cohort for a more thorough examination.

Background: Although congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of pediatric end-stage renal disease (ESRD), little is known about the characteristics exhibited in the infantile period by CAKUT patients who develop ESRD. Further, an efficient screening method for CAKUT diagnosis is not available currently. In the present study, we aimed to develop a method to select infants who potentially have CAKUT from a large group of infants.

Methods: We retrospectively investigated the clinical characteristics of CAKUT patients in the infantile period. The medical records of 101 patients with CAKUT who had undergone dialysis or renal transplantation were reviewed. The data of gestational age, birth weight, oligohydramnios, poor body weight gain, asphyxia, and jaundice were recorded. We attempted to determine the ideal characteristics that could be used to select infants who potentially have CAKUT.

Results: 14 % of patients were born prematurely, 18 % had low birth weight, 79 % had poor body weight gain, 18 % had asphyxia, 8 % had oligohydramnios, and 12 % had jaundice. We found that 82 % of patients had poor body weight gain or oligohydramnios among our patients and regarded these two symptoms as ideal markers for selecting those who potentially have CAKUT (specificity, 95 %; efficacy, 95 %). Further, the age of ≤ 7 months was the most appropriate time for the selection.

Conclusions: For timely diagnosis of CAKUT, we recommend that ultrasound examination and the serum creatinine test be conducted for infants showing poor body weight gain or oligohydramnios at age ≤ 7 months.