Testing for antineutrophil cytoplasmic antibodies (ANCA) is useful for patients with Wegener’s granulomatosis or other systemic vasculitides. When laboratories accede to all requests for ANCA testing however, the results may be difficult to interpret or irrelevant because more than half of positive tests are in patients who do not have a systemic vasculitis. In Portsmouth, UK a policy of selective testing has been in place for ten years and has resulted in more focused requesting of ANCA tests by clinicians.

The laboratory has performed ANCA testing only when the request …