Systemic vasculitis

Routine laboratory tests are useful for monitoring the untoward effects of therapy for systemic vasculitis. Many immunosuppressive agents also affect the bone marrow, so routine complete blood count monitoring is essential to ensure that patients do not become anemic or leukopenic.

For patients at risk for glomerulonephritis, routine renal function monitoring by urinalysis may provide early detection of a disease flare. The frequency of laboratory testing may vary from once every few weeks to once every few months, depending on the patient's baseline indices and previous response to immunosuppressive agents.

After a diagnosis has been established, repeat biopsies are generally not warranted unless the patient is deteriorating or resistant to treatment. In patients with large-vessel vasculitis, serial imaging can be useful to assess disease progression.