**Abbreviations**

ANCA – anti-neutrophil cytoplasmic antibody, APS – antiphospholipid syndrome, CSS – Churg-Strauss syndrome, DAH – diffuse alveolar hemorrhage, GBM – glomerular basement membrane, GN - glomerulonephritis, GPA – granulomatosis with polyangiitis, GPS – Goodpasture´s syndrome, ICU – intensive care unit, IVIG – intravenous immunoglobulin, MCTD – mixed connective tissue disease, MPA – microscopic polyangiitis, MPO myeloperoxidase, NAC – N-acetylcystein, NO –nitric oxide, eNOS – endothelial nitric oxide synthase, iNOS – inducible nitric oxide synthase, PRS – pulmonary-renal syndrome, RA – rheumatoid arthritis, siRNA - small interfering ribonucleic acids, ROS – reactive oxygen species, SLE – systemic lupus erythematosus, WG – Wegener´s granulomatosis
