ABSTRACT
These uncommon diseases are characterised by an inflammatory cell infiltrate into the blood vessel wall. The vasculitis leads to blockage of vascular supply and necrosis of tissues distal to the obstruction. Vasculitis occurs secondary to a variety of inflammatory rheumatic diseases, such as SLE, systemic sclerosis, dermatomyositis, and Sjögren’s syndrome. However the primary vasculitides are less common with a more serious form, such as Wegener’s granulomatosis and microscopic polyarteritis being fatal if untreated. The aetiology of all these diseases remains unclear but hepatitis B
Figure 11.1 Pattern for vascular involvement in vasculitides
and C are commonly involved where these viruses are endemic. In any instance the key to the diagnosis is one widespread multi-system involvement, usually with severe constitutional symptoms with the size of blood vessel involvement dictating the symptoms and defining the disease character (Figure 11.1). In some vasculitides there are circulating antibodies directed against neutrophil cytoplasmic antigens (ANCA) (Figure 11.7 and 11.11). It is probably wise to refer all potential cases because of the difficulty in confirming the diagnosis.
