Impaired protein tolerance test as a marker of early renal dysfunction in type 2 diabetes mellitus

Background: Protein tolerance test measures renal functional reserve that augments during stressful conditions. Aim: This was a clinical study on evaluation of protein tolerance test as marker for early renal dysfunction in Type 2 Diabetes mellitus. The study also compared progression of renal dysfunction with age and duration of Type 2 Diabetes mellitus. Method: Total 104 cases - 54 study group, 50 control group were included. Patients with Type 2 diabetes mellitus were included in the study. Fifty healthy, age and sex matched controls without diabetes or its complications were also included in the study for comparison. Observation: It was found that renal failure was more in patients over 60 years 86% as compared to 16% in the 51-60 years group and 8% in the 41-50 years group. It was found that normal functioning kidney would be able to reduce urine protein after protein tolerance, whereas in patients with renal dysfunction, 17% found to have renal risk and 21% have renal failure. It was demonstrated that normal functioning kidney responded to protein tolerance by increasing eGFR unlike in renal failure cases, eGFR declined after protein tolerance. After protein tolerance normal functioning kidney increased GFR unlike in renal failure cases, serum creatinine levels raised. Prolonged duration of Type II Diabetes mellitus increases risk of renal failure. Conclusion: Patients with renal failure had more persistent elevation of serum creatinine and sustained decrease in GFR as compared to patients with normal renal function or those with mild renal dysfunction.