Contrast Media Induced Nephropathy in Diabetic Renal Disease

Abstract

Diabetes mellitus has been incriminated as a risk factor for radiocontrast-induced nephropathy (CIN) since the 1960’s [39]. Two decades later, the precise risk to the diabetic kidney is still debated with incidence rates ranging from less than 1% to over 30% [31,50,52], especially when complicated by chronic renal failure (CRF). Almost 100% of diabetics with a serum creatinine level (SCr) greater than 400 μmol/l (4.5 mg/dl) can develop CIN after contrast exposure [22,52]. Dialysis is needed in 25–50% of all patients who develop CIN [23,29,49] but in 40–50% of diabetics [16,54], a few permanently [54]. Few studies are confined to diabetic patients and most do not report on diabetic subtypes yet differences in outlook between older and younger diabetics and various subtypes of diabetes almost certainly exist — perhaps Type II diabetic patients are less likely to develop CIN than type 1 patients [22,46]. Methodologic differences between studies and variability in contrast dosages exist. Diagnostic increases in SCr vary between 20% [26] and 50% [12,19,37] over baseline, whereas absolute increases may be as little as 26 μmol/l (0.3 mg/dl) [26] or as liberal as 177 μmol/1 (2.0 mg/dl) [8,9]. A rise in SCr of at least 50% [12,19,38] or 88 μmol/1 (1 mg/dl) [14,19,22,51,52,54] within 48 hours of contrast administration seems acceptable. Furthermore, the applicability of »low osmolality« or »nonionic« radiocontrast materials to the diabetic kidney is unclear. These issues will be addressed in this chapter.