Nephrosonography and renal scintigraphy in evaluation of newborn with renomegaly

Prompt diagnosis of renomegaly in the newborn is necessary for appropriate medical or surgical management to insure maximal recovery of renal function. To investigate both renal structure and function without iodinated contrast infusion, combined ultrasonography and nuclear scintigraphy were evaluated in 17 newborns with renomegaly and 6 infants with cystic renal abnormalities detected in utero. In 18 patients, intravenous pyelography (IVP) and/or voiding cystourethrography (VCUG) were performed subsequently. While ultrasonography or scintigraphy alone provided the major diagnosis in 48 per cent and 30 per cent of cases, respectively, the combination of both studies yielded the major diagnosis in 87 per cent. Subsequent IVP was less informative than combined sonography and scintigraphy in 5 of 15 patients, and VCUG confirmed the final diagnosis in 4 of 13 patients. We conclude that initial evaluation of the newborn with renomegaly should comprise ultrasonography followed by nuclear scintigraphy. This combination of studies provides adequate information to determine subsequent management in nearly 90 per cent of cases without subjecting infants to the risks of contrast infusion or higher doses of diagnostic levels of radiation.