ABC of Rheumatology: RAYNAUD'S PHENOMENON, SCLERODERMA, AND OVERLAP SYNDROMES

Several rheumatological conditions are linked to impaired peripheral circulation. These abnormalities may take various forms, including chilblains, acrocyanosis, and Raynaud's phenomenon. This last condition, described by the French clinician Maurice Raynaud in 1862, occurs in up to 5% of an otherwise healthy population, but may be a link between certain autoimmune rheumatic diseases. Raynaud's disease refers to the development of trophic changes as a result of microcirculatory damage and prolonged local ischaemia. Fortunately, gangrene is relatively rare, and, because patients are often young, recovery may be remarkable. #### Disturbances of peripheral circulatory system Chilblains—Painful, burning or itching erythematous lesions of hands or feet (rarely ulceration) precipitated by damp and cold (especially if inadequate clothing worn) Acrocyanosis—Persistent cold, blue, and rather sweaty appearance, usually of hands Raynaud's phenomenon—Episodic, clearly demarcated two or three phase colour change—white (ischaemia), then often blue (stasis), then red (reactive hyperaemia)–of fingers and sometimes toes (rarely nose, tongue, or ears) in response to cold or, less often, emotion Well defined blanching of skin characteristic of Raynaud's phenomenon. Over 90% of patients with Raynaud's phenomenon are female and, at the time of presentation, are often aged under 25. Up to 5% of patients presenting with the condition eventually develop an autoimmune rheumatic disease. The presence of abnormal nail fold capillaries (detected by capillaroscopy) and antinuclear antibodies are of particular value in predicting this development. View this table: Prevalence of Raynaud's phenomenon in autoimmune rheumatic diseases Primary and secondary Raynaud's phenomenon are distinguished by a combination of clinical examination and laboratory investigations. Physical examination should include assessment of peripheral pulses, measurement of blood pressure in both arms, and examination of the neck for the tenderness often associated with a cervical rib. A negative test for antinuclear antibody in an otherwise healthy patient is reassuring but does not completely exclude subsequent development of an autoimmune rheumatic disease. Different types …