The captopril renogram test has been shown to be a sensitive test for the d
iagnosis of renal artery stenosis in native and transplanted kidneys. Most
reports have involved only stenosis of the main renal artery, Although segm
ental renal artery stenosis has been diagnosed successfully in native kidne
ys, it is not clear whether the captopril renogram test can diagnose segmen
tal renal artery stenosis in a transplanted kidney. The authors report two
cases of successful identification, by the captopril renogram test, of func
tionally significant stenosis in an intrarenal branch of a single transplan
t renal artery.