Microscopic polyangiitis is an ill-defined autoimmune disease which usually presents with pulmonary bleeding and anemia. Laboratory tests show an increased sedimentation rate, reduced red blood count, antineutrophil cytoplasmic antibodies (ANCA) directed against myeloperoxidase (a constituent of neutrophil granules). and protein and red blood cells in the urine. The test for anti-glomerular basement membrane antibody (GBM), which is positive in Goodpasture's syndrome, is negative. more...
This condition, the clinical picture of which may include many features of systemic lupus erythematosis, has been reported to have been caused by antibiotics and also by certain infections.
The customary treatment involves long term dosage of prednisone, alternated or combined with cytotoxic drugs, such as cyclophosphamide or azathioprine.
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