Elemental diets in treatment of acute Crohn's disease.

seven kidneys (5 %), however, showed severe arterial beading of the type previously reported in rejectionl 2; and in another nine kidneys (7 %) there were irregularities in the small renal arteries ranging from minor variations in vessel calibre and course to obvious segments of constriction or dilatation with abrupt terminations to the vessels. All the transplanted kidneys demonstrating these vascular abnormalities were undergoing rejection. One of the patients in whom aneurysms were demonstrated had arteriography of the transplanted kidney performed on two occasions; the first arteriogram showed normal intrarenal vessels, the second study one year later showed multiple small aneurysms which had developed during the course of rejection of the kidney. There was considerable overlap between the different types of arteriographic abnormality seen in rejecting transplant kidneys; the 20 kidneys comprising the three groups described above demonstrated a spectrum of vascular changes ranging from mild variations in vessel calibre at one extreme to multiple aneurysms at the other. In summary, multiple intrarenal aneurysms or severe preaneurysmal beading were demonstrated in 8 % of 136 arteriograms performed on malfunctioning transplanted kidneys. In a total series of 918 renal arteriograms rejection of a transplant was second only to polyarteritis nodosa as a cause of this type of aneurysm. Many causes of renal aneurysm are known,3 but the aneurysms seen in transplant rejection are most similar in their arteriographic appearance to those occurring in polyarteritis nodosa3 or drug abuse.4