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Proteinuria Differential  -  Outlines in Clinical Medicine on Physicians' Online 2001

A. Tubular Proteinuria

  1. Little albumin in UPEP analysis
  2. Low molecular weight compounds including ß2-microglobulin, lysozyme, Ig Light Chains
  3. Urinary protein in 24 hours usually 1-3gm
  4. Usually due to hereditary tubular defects, other tubular damage
  5. In absence of casts or hematuria, usually benign
  6. Medications toxic to tubules (or interstitium): gold, NSAIDs, heavy metals
  7. Bence-Jones Proteins are immunoglobulin light chains, usually due to multiple myeloma

B. Glomerular Proteinuria

1.  Significant quantities of albumin in urine signify glomerular damage

2.  Nephrotic Range Protein Excretion:
a.>3.5gm protein / 24 hour urine in person with normal serum albumin
b.With abnormal >0.4mg protein/mmol (3.5gm/dL) creatinine

3.  Microalbuminuria
a.Urinary albumin excertion 20-199µg/min
b.Also defined as >25µg/dL of glomerular filtration rate

4.  Non-Nephrotic Glomerular Proteinuria
a.Absence of hematuria, casts, azotemia
b.Hereditary Syndromes (usually benign)
c.Diabetes mellitus
e.Rheumatoid Arthritis

5.  Primary Glomerular Diseases
a.Membranous Glomerulonephritis
b.Proliferative Glomerulonephritis
c.Minimal Change Disease (mostly children)
d.Focal and Segmental Sclerosing Glomerulonephritis (FSGS)

6.  Glomerular Dysfunction Secondary to Multisystem Disease
a.Diabetes Mellitus
b.Hypertension, hypercholesterolemia, smoking tobacco [1]
c.Immune Complex Diseases: Systemic Lupus Erythematosus, Polyarteritis Nodosa
d.Infection: Bacterial, Viral including HIV
e.Malignancy: Leukemia, Lymphoma, Carcinoma
f.Allergic Reactions

7.  Renal Vein Thrombosis

8.  Primary and Scleroderma Renal Crisis (hypertensive emergency)

9.  Proteinuria is a weak risk factor for all cause mortality and for cardiovascular disease


1.Cirillo M, Senigalliesi L, Laurenzi M, et al. 1998. Arch Intern Med. 158(17):1933

2.Culleton BF, Larson MG, Parfrey PS, et al. 2000. Am J Med. 109(1):1