In a patient with hematuria and pulmonary hemorrhage, which finding supports Goodpasture syndrome?

In a patient with hematuria and pulmonary hemorrhage, which finding supports Goodpasture syndrome?

• A. RBC casts on urinalysis
• B. Elevated anti-GBM antibodies in serum
• C. Crescent formation on kidney biopsy only
• D. Crescent formation on biopsy with positive anti-GBM antibodies in kidney and lung alveoli

Answer: (D)

Goodpasture syndrome occurs when autoantibodies attack the type IV collagen in basement membranes of both the kidneys and the lungs, causing rapidly progressive glomerulonephritis with crescents and pulmonary hemorrhage. The strongest evidence is finding crescents on kidney biopsy together with anti-GBM antibodies present in the basement membranes of both kidney and lung alveoli. This combination shows that the same autoantibody is driving injury in both organs, matching the dual blood-tinged presenting features. RBC casts can appear in many glomerular diseases and aren’t specific; finding anti-GBM antibodies in serum supports the diagnosis but isn’t definitive without demonstrating organ involvement. Crescent formation alone points to severe glomerular injury but not the underlying cause. The concurrent crescents in the kidney and anti-GBM antibody activity in the lung alveoli best identifies Goodpasture.

Goodpasture syndrome occurs when autoantibodies attack the type IV collagen in basement membranes of both the kidneys and the lungs, causing rapidly progressive glomerulonephritis with crescents and pulmonary hemorrhage. The strongest evidence is finding crescents on kidney biopsy together with anti-GBM antibodies present in the basement membranes of both kidney and lung alveoli. This combination shows that the same autoantibody is driving injury in both organs, matching the dual blood-tinged presenting features.

RBC casts can appear in many glomerular diseases and aren’t specific; finding anti-GBM antibodies in serum supports the diagnosis but isn’t definitive without demonstrating organ involvement. Crescent formation alone points to severe glomerular injury but not the underlying cause. The concurrent crescents in the kidney and anti-GBM antibody activity in the lung alveoli best identifies Goodpasture.