Final answer:
The first manifestation of renal nephropathy in patients with diabetes is usually microalbuminuria, a condition characterized by a small amount of protein in the urine. This symptom often goes unnoticed, as it can occur without any other signs of illness, thus routine testing is essential for early detection.
Step-by-step explanation:
Joe has had diabetes for 10 years and has been diagnosed with diabetic nephropathy, indicating damage to his kidneys due to prolonged high blood sugar levels. The first manifestation of kidney dysfunction in diabetic nephropathy often includes microalbuminuria, which is the presence of a small amount of protein in the urine. Over time, symptoms can escalate to chronic kidney disease (CKD), where kidney function progressively declines, eventually leading to the need for dialysis or a kidney transplant if it progresses to end-stage renal disease.
It's important to note that diabetic nephropathy could be asymptomatic in the initial stages and may not show any symptoms until significant damage has occurred. Routine testing for microalbuminuria is a critical part of managing diabetes to catch early signs of renal involvement. Poorly controlled blood glucose, high blood pressure, a history of cigarette smoking, and a family history of kidney problems are risk factors for developing this condition.