Demonstration of anti-GBM antibodies in the blood and biopsy specimens is diagnostic of Goodpasture syndrome.
Tests that indicate the presence of Goodpasture syndrome are:
- The pH of the coughed up blood should be checked. Blood coughed up from the lungs is not acidic. If it is acidic, the blood has most likely come from the stomach and not the lungs
- The diffusion capacity of carbon monoxide test is increased if bleeding is present in the lungs
- Lung function tests show a decrease in alveolar gas volume, total lung capacity and vital capacity
- Chest x-rays and CT scan may also help to diagnose lung disease
- Bronchoscopy (a procedure in which a tube is introduced to examine the lungs) may be used to check the degree of lung involvement and rule out other causes of bleeding
- Confirmation of the diagnosis may be done by immunofluorescence of lung tissue to detect the antibodies, and electron micrograph studies
- Urine examination may show the presence of protein, blood and casts in the urine (casts are tiny cylindrical particles that are present in the urine in certain disease conditions).
- Blood tests show an increase in blood urea nitrogen and creatinine levels. They also show the presence of circulating antibodies to glomerular basement membrane.
- A kidney biopsy helps to diagnose the condition. It shows the linear deposits of the antibody IgG with crescent formation.
- Other blood tests:
- A complete blood routine examination may be done to detect the presence of anemia
- Laura Bergs. Goodpasture Syndrome. Crit Care Nurse 2005;25:50-58