Glomerular Basement Membrane Antibodies, IgG
Label Mnemonic: GBM
Epic Lab Code: LAB1255
Downtime Form: A-1a General Laboratory Requisition
Chemistry
6240 RCP
356-3527
Specimen(s):
Serum
Collection Medium:
Red top tube 5 mL (Clot Activator)
Minimum:
Adult - 5 mL; red top tube Pediatric - 2 mL; red top tube
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
3 hours (upon receipt in laboratory)
Reference Range:
Negative: < 0.4 antibody index (AI)
Equivocal: 0.4-0.9
Positive: 1.0 AI or greater
Interpretive Data:
Glomerular basement membrane (GBM) antibodies are used for evaluating with rapid onset renal failure or pulmonary hemorrhage and as an aid in the diagnosis of Goodpasture syndrome in conjunction with clinical history and physical examination. Positive results for GBM antibodies are consistent with Goodpasture syndrome. GBM antibodies are highly specific for Goodpasture syndrome. The sensitivity of this test is approximately 87% in untreated patients with systemic disease.
Comments:
Assay methodology and reference ranges changed February 5, 2013.

References:
Pusey CD. Anti-glomerular basement membrane disease. Kidney Int 2003; 64:1535-1550.
Methodology:
Multiplex flow immunoassay
CPT Code:
83520