How to perform and analyse biopsies in relation to connective tissue diseases

Rheumatic and, in particular, connective tissue diseases involve many organ systems in addition to the joints. These include the skin and underlying tissues, muscles, salivary glands, nerves, kidneys and blood vessels. Biopsy specimens of these tissues can be helpful in establishing a diagnosis, assessing the extent and severity of organ involvement and monitoring therapy. This article describes the practical information on a clinical diagnosis that might indicate a need for biopsy. It outlines how to prepare the patient, how to perform the biopsy, what results are to be expected and which sequelae are possible.