THE SYNDROME OF LUNG HEMORRHAGE AND NEPHRITIS IS USUALLY AN ANCA-ASSOCIATED CONDITION

Background: In the absence of evidence of arteritis or Wegener's granu lomatosis, the syndrome of lung hemorrhage and nephritis has been comm only associated with anti-glomerular basement membrane (GBM) antibodie s. However, it has been increasingly recognized that many cases are as sociated with antineutrophil cytoplasmic antibodies (ANCAs). Objective : To review available clinical and pathologic findings to determine th e diseases accounting for lung hemorrhage and nephritis. Methods: We s tudied the records of 750 patients from whom serum samples were sent t o our laboratory for anti-GEM antibody assays between 1981 and 1993 an d found 88 patients with evidence of lung hemorrhage and nephritis. Se rum samples were retested, using current methods, for anti-GEM antibod ies (against noncollagenous 1 domain of the alpha 3 chain of type IV c ollagen) and for antibodies to proteinase 3 and myeloperoxidase-the tw o types of ANCA of diagnostic value. Results: Of 88 patients with evid ence of lung hemorrhage and nephritis, 48 had ANCAs, six had anti-GBM antibodies, and seven had both. In 48 patients with ANCAs, the patholo gic findings that accounted for the pulmonary renal syndrome were pauc i-immune necrotizing and crescentic glomerulonephritis and pulmonary c apillaritis. Only eight had convincing evidence (during life) of Wegen er's granulomatosis and only one other had documented arteritis. In 27 patients without ANCAs or anti-GBM antibodies, a variety of unrelated renal and pulmonary diseases were found. Conclusions: The largest gro up of patients who present with the syndrome of lung hemorrhage and ne phritis have ANCAs and not anti-GBM antibodies. Appropriate tests for antibodies to proteinase 3, antibodies to myeloperoxidase, and anti-GB M antibodies provide reliable guides for making a diagnosis in patient s with this pulmonary renal syndrome.