Raynaud's phenomenon in undifferentiated connective tissue disease (UCTD)

The aim of this study was to ascertain which clinical and immunological factors are associated with Raynaud’s phenomenon (RP) in patients with undifferentiated connective tissue disease (UCTD) and to investigate microvascular involvement. A total of 78 patients were evaluated. They all showed symptoms suggestive of a connective tissue disorder (CTD), but did not fulfil the criteria for any of the defined CTDs. They all had a disease duration of at least 1 year. Nailfold capillaroscopy (NC) was performed using a computerised videomicroscope. We diagnosed RP in 52.5% of our patients. Patients with RP showed a higher occurrence of oesophageal dysmotility (p=0.001) and anti-ribonucleoprotein (RNP) antibodies (p=0.004) than those without RP. The distinguishing capillaroscopic characteristics of UCTD patients with RP were widened and irregularly enlarged loops (75 and 55%, respectively), giant capillaries (35%), and less than two haemorrhages per finger (40%). The combination of features indicative of a ‘slow’ scleroderma pattern was present in 18 of 40 patients with UCTD and RP (p=0.0003). Only 3 of the original 78 patients (3.8%) developed a definite CTD. In none of our patients did we observe avascular areas or changes from the original capillaroscopic pattern during follow-up examination. Our study indicates that patients with UCTD would seem to have a benign form of RP, since they show the absence of cutaneous complications, the existence of a mild microvascular damage and a stable nailfold capillary pattern. Further examinations of these patients will be required in order to confirm our findings.