[en] Dynamic scintigraphy with computer renography (¹³¹I-hippuran, ¹²⁵I-hippuran, sup(99m)Tc-DTPA), indirect angiography (sup(99m)Tc-albumin), static scintigraphy (¹⁹⁷Hg-promeran, sup(99m)Tc-citrate, sup(99m)Tc-calcium-gluconate, sup(99m)Tc-sulphuric colloid) and RIA determination of plasma renin activity were carried out in 105 patients with complications after renal transplantation. In the diagnosis of the specific complications the most valuable methods were the following: indirect angiography in the diagnosis of renal arterial thrombosis; dynamic scintigraphy in the case of ureteral occlusion; static scintigraphy (¹⁹⁷Hg-promeran) in infarction, carbuncle or abscess of the transplantatum. The methods applied provided ''good'' information in the following cases: indirect angiography in venous thrombosis and acute tubular necrosis; dynamic scintigraphy in venous and arterial thrombosis, ureteral occlusion, and acute renal failure; static scintigraphy with sup(99m)Tc-citrate in infarction and abscessus, with sup(99m)Tc-calcium-gluconate in ureteral occlusion, with sup(99m)Tc-sulphuric colloid in acute tubular necrosis; RIA determination of plasma renin activity in acute tubular necrosis. In the different pathological conditions the examinations not mentioned above gave poor or negative results. (L.E.)