What is the hallmark of diabetic nephropathy, and an early marker?

• A. Albuminuria; microalbuminuria (30-300 mg/day) as an early marker
• B. Hematuria; proteinuria (300-1000 mg/day)
• C. Reduced GFR; creatinine clearance decreased
• D. Proteinuria without albuminuria

Answer: (A)

Diabetic nephropathy is defined by the kidney’s filter becoming leaky to albumin, so albumin shows up in the urine. That albuminuria is the hallmark feature. Within that window, the earliest detectable stage is microalbuminuria, a small but abnormal amount of albumin in the urine that requires a sensitive test to pick up. Catching microalbuminuria early matters because it flags kidney involvement from diabetes and offers a chance to slow progression with interventions like good blood pressure and blood sugar control and treatments that reduce albumin loss. As the disease progresses, protein in the urine increases to larger amounts (macroalbuminuria), and kidney function declines later on. Hematuria is not typical of diabetic nephropathy and suggests other kidney issues. Proteinuria without albuminuria doesn’t fit the usual pattern here, since albumin is the primary protein involved in this condition.