Laboratory tests may reveal an increased sedimentation rate, elevated CRP, anemia and elevated creatinine due to kidney impairment. An important diagnostic test is the presence of perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) with myeloperoxidase specificity (a constituent of neutrophil granules), and protein and red blood cells in the urine. In patients with neuropathy, electromyography may reveal a sensorimotor peripheral neuropathy. Differential diagnosis The signs and symptoms of<unk>  may resemble those of granulomatosis with<unk>  (GPA) (another form of small-vessel vasculitis) but typically lacks the significant upper respiratory tract involvement (e.g., sinusitis) frequently seen in people affected by GPA.
Microscopic polyangiitis
Granulomatosis with polyangiitis
Polyarteritis nodosa
Lupus vasculitis
Eosinophilic granulomatosis with polyangiitis
Thromboangiitis obliterans
Transplant glomerulopathy
Thin basement membrane disease