proteinuuria

Proteinuria is the presence of an abnormal amount of protein in the urine. It can be transient or persistent and may reflect healthy variation, dehydration, or an underlying kidney disorder. The term proteinu ria is sometimes encountered as a misspelling of proteinuria.

Proteinuria is commonly classified as transient or persistent. Persistent proteinuria is further divided by mechanism into glomerular, tubular, or overflow proteinuria. Microalbuminuria refers to small increases in albumin in the urine and is used as an early marker of kidney disease.

Causes include diabetes mellitus and hypertension, which can damage the glomerular filter; glomerulonephritis and polycystic kidney disease; pregnancy-related conditions such as preeclampsia; and, less commonly, infections or inflammatory states. Transient proteinuria can occur after fever, exercise, dehydration, or urinary tract infections. In rare cases, overflow proteinuria arises from increased production of light chains in multiple myeloma.

Diagnosis starts with a urinalysis dipstick, which is most sensitive to albumin. Confirmation and quantification use the urine albumin-to-creatinine ratio on a spot sample or a 24-hour collection. Additional tests may include kidney function tests, imaging, and, if indicated, urine protein electrophoresis or serum studies for systemic diseases.

Management focuses on the underlying cause and reduction of kidney injury. In diabetes and hypertension, inhibitors of the renin–angiotensin system (ACE inhibitors or ARBs) decrease proteinuria and slow progression. Lifestyle measures, blood pressure control, and careful monitoring are essential, with more intensive therapy for high-risk patients.