Here is another glomerulus with an epithelial crescent squashing the glomerular tufts from all sides. RPGN may be idiopathic or may result from SLE, post-infectious GN (as in some cases of post-infectious GN), from various types of vasculitis, and from Goodpasture syndrome.

Question: If Goodpasure syndrome is suspected, what serologic test should be obtained?

AnswerThere is likely to be detectable antiglomerular basement membrane (anti-GBM) autoantibody with Goodpasure syndrome.