[Microalbuminuria: theoretical bases and new applications]

Area of Science:

• Nephrology and Clinical Biochemistry
• Urine protein analysis
• Biomarker discovery

Context:

• Historically, "clinical proteinuria" (≥300 mg/dl) was the primary indicator of renal disease.
• Traditional biochemical tests lacked sensitivity to detect lower protein levels.
• Advancements in detection technology revealed "microproteinuria" below traditional limits.

Purpose:

• To redefine the diagnostic significance of urinary protein excretion.
• To evaluate the pathophysiologic, diagnostic, and prognostic role of microproteinuria.
• To explore microproteinuria as an early marker for diabetic nephropathy and cardiovascular diseases.

Summary:

• Microproteinuria, defined as urinary protein excretion between physiological and clinical levels, is a critical early indicator.
• In diabetics, it predicts nephropathy, renal failure, and macroangiopathic complications.
• It also serves as a sensitive marker for cardiovascular diseases in hypertensive and non-hypertensive individuals.

Impact:

• Challenges the traditional view of proteinuria onset in diabetic nephropathy.
• Establishes microproteinuria as a crucial early warning sign for kidney and cardiovascular health.
• Opens new avenues for research into non-diabetic glomerulopathies and broader clinical applications.