In patients with Raynaud's phenomenon (RP), the role of medical history, capillaroscopy, and autoantibodies in order to provide an early diagnosis of connective tissue disease (CTD) were examined. 115 consecutive adults with uni-, bi-, or triphasic colour changes of the fingers were studied. RP was bilateral in 92.7% of patients. The middle finger was significantly more affected. A lack of association between fingers affected by RP and fingers with capillary abnormalities was observed OR = 0.75 (0.34-1.66). RP with the cyanotic phase had a higher risk at capillaroscopy to have hemorrhages OR = 4.46 (1.50-13.30) and giant capillaries OR = 24.85 (1.48-417.44). The thumb and triphasic involvement have an OR of 1.477 and 1.845, respectively. RP secondary to systemic sclerosis (SSc) had greater value of VAS pain (p = 0.011). The presence of anti-centromere antibodies was significantly associated with a higher risk of SSc (p < 0.001). 44.3% of subjects had uniphasic blanching of the fingers, and among these, 27% was diagnosed as having an overt or suspected CTD. Markers of a potential development of CTDs include severe RP symptoms, positive autoantibodies, and capillary abnormalities. These data support the proposal to not discharge patients with uniphasic blanching of the fingers to avoid missing the opportunity of an early diagnosis.