Thermography and nailfold capillaroscopy as noninvasive measures of circulation in children with Raynaud's phenomenon.

OBJECTIVE: To determine in a pilot study the feasibility of noninvasive techniques of (a) measurement of rewarming response after a standard cold challenge test (using thermographic imaging) and (b) measurement of nailfold capillary dimensions using video capillaroscopy, in the assessment of children presenting with Raynaud's phenomenon (RP).

METHODS: Ten children with RP and 10 age matched healthy controls were studied. No child had definite evidence of underlying connective tissue disease.

RESULTS: Children with RP had abnormal rewarming curves. The gradient of the rewarming curve was significantly lower in children with RP (median 1.5 vs 5.0 degrees C/min in controls; p = 0.015), and there was a trend for the lag time (the interval between the end of the cold challenge and the onset of rewarming) to be increased in children with RP (median 4.7 vs 0.5 min in controls; p = 0.08). Capillary dimensions were measured in 7 of the children with RP, and were similar to those of healthy controls.

CONCLUSION: Thermography and nailfold capillaroscopy are feasible in children and should be further evaluated.