Roadmap to vasculitis: a rheumatological treasure hunt: Part III. Laboratory evaluation and imaging

In the third part of this four part review, we already have the stop sign and our three road signs pointing to secondary vasculitides, pseudovasculitides and primary vasculitides behind our back and we have also passed the first milestone, where “patient history and physical examination” was written with large black block letters. GP can get far with simple blood, urine and stool tests and routine X-rays (second milestone). Almost all vasculitides of clinical significance are characterized by increased ESR and raised C-reactive protein levels and often also by normocytic normochromic anaemia, leucocytosis, eosinophilia and thrombocytosis. Urine test may demonstrate haematuria, proteinuria and cylindruria, X-ray of the paranasal cavities chronic sinusitis and chest X-ray shadowing and cavitations. Serological tests may disclose an unexpected hepatitis B or C or perhaps ANCA. The possibilities described form such a cornucopia that we need to have our patient history and physical examination right for the right picks. This is even more pertinent when we take to the sledgehammer in the referral centres (third milestone) and deal with the histopathology of vasculitides as hopefully seen in biopsies rather than autopsies or perform invasive radiology. High resolution colour Doppler ultrasound offers a useful, non-invasive method for the diagnosis and guidance of an eventual biopsy site in temporal arteritis and is helpful in the diagnosis of Takayasu's arteritis and Kawasaki disease. Aortic arch, mesenteric, splanchnic or renal angiographies, MRI, contrast-enhanced CT, gadolinium-enhanced magnetic resonance angiography and positron emission tomography are dealt with but require the right patient and the right “doctor decision maker” not to cause harm and to avoid waste of scant resources.