Captopril challenge test

In medicine, the captopril challenge test, also CCT, is a non-invasive test used to help diagnose renal artery stenosis.

The CCT, in adults, has a high sensitivity, but a low specificity. A better test for diagnosing renal artery stenosis is subtraction renal angiography.

How it is done
The CCT is performed by measuring the renin prior to and following the administration of captopril, an angiotensin converting enzyme inhibitor. A CCT is considered positive if the renin levels increase substaintially or the baseline renin level is abnormally high.

Use of the CCT in children
The CCT has not been found to be very useful in children.