03/17/2026
Proteinuria is not a diagnosis. It’s a starting point.
In this first episode of the series, I break down how I approach proteinuria clinically and how to categorize it before jumping to conclusions.
Think in three buckets:
• Pre-renal – often transient and related to systemic factors like stress, fever, inflammation, hypertension, corticosteroid exposure, or in rare cases overflow proteinuria from gammopathies
• Post-renal – inflammation, infection, hemorrhage, or contamination distal to the kidney
• Renal – intrinsic kidney disease, most commonly glomerular
A urine dipstick is just a screening tool. If you see protein, confirm and quantify with a urine protein:creatinine ratio, ideally using pooled samples collected over multiple days. Always interpret in the context of sediment, blood pressure, and baseline lab work.
Clinical pearl: if total protein is low but globulins are normal and albumin is decreased, start thinking renal loss over GI loss.
Proteinuria matters because persistent protein loss accelerates kidney damage, even in patients that appear clinically stable.
Next week we’ll narrow the focus to renal proteinuria and protein-losing nephropathy.
Save this for your next proteinuric case and let me know what questions you have below.
