Incidence and clinical presentation of terminal renal failure in diabetic patients

Background: In all Western countries there is a dramatic increase of diabet ic patients who need renal replacement therapy. Very different figures for incidence and prevalence have been reported. There is a strong suspicion th at the epidemiological dimension of the problem has been underestimated in many of the statistics. Methods: In a retrospective analysis we assessed all patients admitted to t he Department Internal Medicine Heidelberg from January 1(st) 1998 - Decemb er 31(st), 2000 for renal replacement therapy, i.e. hemodialysis or CAPD, b ecause of acute or chronic renal failure. We counted the number of known di abetic patients (i) with signs of classical diabetic nephropathy (enlarged kidneys, proteinuria > 1 g/24h +/- retinopathy), (ii) with atypical renal c hanges (contracted kidneys, proteinuria < 1 g/24 h) and (iii) diabetic pati ents with (coincident) primary chronic renal disease as well as (iv) the pr oportion of patients in whom the diagnosis of diabetes had been unknown whe n uremia had supervened. Results: Dialysis treatment was started in 568 patients for acute (ARF; n = 341) or chronic (CRF; n = 227) renal failure. 95/341 (28%) patients with A RF had diabetes. ARF occured in no less than 12/95 (13%) of the diabetic pa tients after cardiological intervention. Diabetes was present in 111/227 pa tients with CRF (7 type 1, 104 type 2); in 12/111 patients the diagnosis of diabetes was established only after admission. Only 67/111 of the diabetic patients (60%) had classical signs of diabetic nephropathy, in 14/111 (13% ) patients the classical signs of diabetic nephropathy were absent and in 3 0/111 (27%) non-diabetic primary chronic renal disease was present. Conclusion: The study illustrates the importance of diabetes for the epidem iology of renal failure. A sizeable proportion of patients with acute renal failure have diabetes, typically patients with pre-existing nephropathy in whom this complication supervenes during diagnosis and treatment of late d iabetic complications. In diabetic patients with chronic renal failure the presentation is frequently atypical and non-diabetic primary renal disease is present more frequently than expected by chance. In a sizeable proportio n of patients diabetes had not been diagnosed by the time chronic renal fai lure occurred.