What is an early screening marker for diabetic nephropathy?

• A. Microalbuminuria (e.g., 30–300 mg/day)
• B. Macroalbuminuria (>300 mg/day)
• C. Serum Creatinine Rise
• D. GFR Decrease

Answer: (A)

An early screen for diabetic nephropathy looks for microalbuminuria, which signals initial glomerular damage from diabetes. Microalbuminuria is defined as about 30–300 mg of albumin excreted in urine per day (or an albumin-to-creatinine ratio in the same range). It appears before overt protein leakage and before the filtration rate begins to fall, so it is the earliest detectable sign of diabetic kidney involvement. In contrast, macroalbuminuria (>300 mg/day) reflects established nephropathy, and rises in serum creatinine or decreases in GFR tend to occur later in the disease. Detecting microalbuminuria allows earlier intervention—better glycemic and blood pressure control and use of ACE inhibitors or ARBs—to slow progression.