[Diagnosis of vascular acrosyndromes].

Vascular acrosyndromes are associated with vasomotor disorders. They may be paroxysmal, like Raynaud's phenomenon, whitening of the fingers on exposure to cold, or erythromelalgia, a painful form of erythema induced by exposure to heat. Others are permanent or semi-permanent, such as acrocyanosis, chilblains, spontaneous haematoma of the fingers, acrocholose and digital ischaemia or necrosis. Diagnosis of the type of acrosyndrome at issue is based primarily on clinical examination and history-taking. Capillaroscopy and antinuclear antibody assay are key examinations essential for distinguishing between primary and secondary Raynaud's phenomenon and connective tissue disorders. Complete blood counts, screening for thyroid dysthyroidism, and antinuclear antibody assay can help distinguish between primary erythromelalgia and erythromelalgia secondary to a systemic disease, principally myeloproliferative syndrome. In the case of acrocyanosis, spontaneous digital haematomas and typical bilateral chilblains, examinations are of no value. For the other permanent and semi-permanent acrosyndromes such as digital ischaemia and purpuric or livedoid lesions, screening for arterial or thrombotic disease is necessary.