My son has hydronephrosis of his right kidney and has had two surgeries when he was 1 year old. He is now 8 and had a renal scan and the results state that he ha significant pelvicalyceal retention on the right which clears following lasix administration. Should we be concerned with the findings?
Hi, Thanks for writing in. Your son might have had congenital HY Chat Doctor.  The present renal scan at 8 years shows that the kidney is bulging out due to urine in the collecting system, but this becomes normal when there is increased force in the kidney after giving lasix which is a diuretic. Las ix administration is a method to study real and apparent swelling of the renal collecting system. Since the swelling in pelvicalyceal system disappears after taking lasix, it is conclusive that he does not have any real obstruction in the kidney collecting system and the swelling that is apparent on the scan is temporary in nature. It will be good to do blood tests for kidney functions regularly as advised by his doctors to make sure the kidneys are working fine and serum creatinine and blood urea values are in the normal range.