Clinicopathological correlation in vasculitis: the continuing importance of biopsy in the era of biomarkers

Abstract

Vasculitis refers to autoimmune inflammatory conditions that damage blood vessel walls, causing diverse symptoms from isolated skin lesions to fatal involvement of the kidneys, lungs, nervous system, or blood vessels themselves. The increasing availability of various non-invasive biomarkers, such as ANCA profiles, complement studies, and radiographic imaging, has improved diagnostic accuracy and helped identify vasculitis at an early stage. However, these biomarkers have limitations in sensitivity and specificity and do not provide direct insight into the extent of tissue damage. Therefore, biopsy and histopathology remain unique in that they demonstrate the underlying inflammatory process within the affected vessels and surrounding tissues. Nevertheless, a biopsy has its own set of constraints. The outcome and diagnostic yield of biopsy for diagnosing vasculitis may be influenced by the appropriate choice of biopsy site, adequate tissue sampling, timing of the procedure, and prior use of corticosteroids or immunosuppressive therapy.