Background. Candida species commonly cause urinary tract infection in infants admitted to neonatal intensive care units. The purpose of this study was to describe the natural history of renal candidiasis as evidenced by sonography in infants with candiduria.
Methods. The medical records of all infants who developed candiduria during their neonatal intensive care hospitalization between 1982 and 1993 were reviewed. Candiduria was defined as the isolation of Candida from (1) one or more specimens obtained by bladder catheterization or suprapubic aspiration, (2) one or more voided specimens and concurrent positive cultures from another sterile body site or (3) one or more voided specimens and changes on renal ultrasound consistent with renal candidiasis. Renal ultrasounds were retrospectively reviewed by one pediatric radiologist. Nonshadowing echogenic foci were considered evidence of renal fungus balls.
Results. Forty-one infants with candiduria were identified. Thirty-six infants underwent 1 or more renal imaging studies (ultrasonography, 35; computerized tomography, 1). The incidence of renal candidiasis in neonates with candiduria, defined as renal fungus balls or renal fungal abscess, was 42%. Of the 13 patients who had sonographic abnormalities suggestive of renal fungus balls, 7 had abnormalities on the first ultrasound obtained after the discovery of candiduria, whereas 6 patients developed abnormalities between 8 and 39 days later.
Conclusions. Serial renal ultrasounds are required to reliably detect late appearing renal fungus balls in neonates with candiduria. Complications requiring surgical intervention, like urinary tract obstruction, were uncommon.