Study of Ischemia-Modified Albumin as Marker of Vascular Injury in Diabetic Nephropathy

Background: Diabetes mellitus (DM) is strongly correlated to ischemia caused by stress that is involved in dysfunction of endothelium leading to angiopathy, particularly diabetic nephropathy (DN). Immediately after occlusion of an artery, free radical production paired with reduced antioxidant defensive response and related ischemia in DM result in changes in the tertiary structure of human serum albumin; therefore, it is called ischemia-modified albumin (IMA). The aim of our work was to evaluate IMA as marker of vascular injury in DN.

Patients and Methods: This trial was conducted on 25 normal individuals as a control group (I) and 75 cases with type II DM. Cases have been subdivided into Group II: 25 diabetic cases with normal albumin in urine, Group III: 25 diabetic cases with albumin in urine and glomerular filtration rate >60 ml/min/1.73m2 and Group IV: 25 diabetic cases with albuminuria and glomerular filtration rate <60ml/min/1.73m2. Medical history, clinical features and laboratory investigations which include the serum IMA have been carried out to all cases.

Results: Compared to the control group, considerably greater serum levels of IMA have been reported in Diabetic cases there had been a wide variation in IMA among the 4 groups. There were considerable +ve correlations among serum IMA and DM duration, blood urea, serum creatinine, UACR, FBS, PPBS and HBA1c. A considerable -ve correlation among serum IMA and eGFR was observed. IMA had an optimal cutoff value≥90 ng/ml with 0.92 area under ROC curve, 96% sensitivity and 92% specificity (p-value<0.001).

Conclusion: IMA could function as a glycemic control marker and a sensitive indicator for DN.