Nail fold capillaroscopy findings in patients with primary fibromyalgia.

The nail fold capillary morphology and blood flow were examined by capillaroscopy in 10 patients with primary fibromyalgia. Only slight morphological anomalies such as moderate enlargement of capillary loops and variations in calibre were found. No obvious correlation emerged between capillary morphology and the duration of the disease, smoking, or history of Raynaud's phenomenon. Three patients with a history of Raynaud's phenomenon showed sluggish capillary flow correlated with subnormal skin temperature during registration. The findings suggest that marked generalized capillary abnormality such as that often involving the nail fold capillaries in many connective tissue disorders is not a prominent feature of primary fibromyalgia.