Glomerular Basement Membrane Antibodies, IgG, Serum
Evaluating patients with rapid onset renal failure or pulmonary hemorrhage, as an aid in the diagnosis of Goodpasture syndrome
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Antibodies to glomerular basement membrane (GBM) antigens cause glomerulonephritis, Goodpasture syndrome (glomerulonephritis, often with rapid onset renal failure, and pulmonary hemorrhage), and, less commonly, pulmonary hemosiderosis.(1) Nephrogenic GBM antigens are associated with the noncollagenous carboxyl extension of type IV procollagen. The immunologic stimuli that elicit production of GBM antibodies are not known. There is some evidence of a genetic association with HLA-DR2.
GBM antibody-mediated glomerulonephritis and Goodpasture syndrome occur with a bimodal age distribution primarily in males ages 20 to 40 and in patients older than age 50. Glomerulonephritis without pulmonary involvement is more common in the older age group, and shows a female predominance.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
<1.0 U (negative)
> or =1.0 U (positive)
Reference values apply to all ages.
Positive results are consistent with Goodpasture syndrome. Glomerular basement membrane antibodies detected by immunoassay have been reported to be highly specific for Goodpasture syndrome. The sensitivity of this test approaches 87% in untreated patients with systemic disease.(1)
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
A positive test for glomerular basement membrane (GBM) antibodies cannot be relied upon exclusively to establish the diagnosis of a disease mediated by GBM antibodies. Weakly-positive test results may occur in other immune-mediated diseases, and renal or lung biopsy is often required to establish the diagnosis.
If patient is being evaluated for autoimmune skin disease, order CIFS / Cutaneous Immunofluorescence Antibodies (IgG), Serum for evaluation of anti-intercellular substance (ICS) and antibasement membrane zone (BMZ) antibodies.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Pusey CD: Anti-glomerular basement membrane disease. Kidney Int 2003;64:1535-1550