Nailfold videocapillaroscopy in primary antiphospholipid syndrome (PAPS)

To evaluate microcirculatory changes (functional and morphological) in primary antiphospholipid syndrome (PAPS) patients.

Thirty-one patients were examined using nailfold videocapillaroscopy (18 PAPS patients and 13 healthy subjects). The patients were subdivided into two subgroups, with lupus anticoagulant (n = 8) and with anticardiolipin (n = 10) antibodies. Capillary morphology was determined; diameters ( micro m) and functional capillary density (FCD, number capillaries/mm2) were measured in control conditions. Blood flow velocity (CBFV, mm/s) was also evaluated at rest and after release of 60 s arterial occlusion.

The percentage of subjects with at least one morphological alteration in the observed capillaries was 77.8% for patients and 21.3% for healthy subjects. Capillary diameters ( microm) [afferent (AD), apical (APD) and efferent (ED)] were significantly smaller (mean +/- s.d.: AD-PAPS, 7.4 +/- 2.1; control, 9.1 +/- 2.6, P = 0.063; APD-PAPS, 11.6 +/- 2.3; control, 14.4 +/- 3.8, P = 0.015; ED-PAPS, 8.4 +/- 2.0; control, 10.9 +/- 3.2, P = 0.011) in PAPS patients compared with controls. FCD (PAPS, 8.5 +/- 3.2; control, 8.3 +/- 2.9, P +/- 0.862), mean resting CBFV (PAPS, 0.73 +/- 0.31; control, 0.88 +/- 0.41, P = 0.278), mean peak CBFV after occlusion (PAPS, 1.07 +/- 0.52; control, 1.59 +/- 0.91, P = 0.063) and mean time (s) to reach it (PAPS, 5.2 +/- 1.7; control, 4.6 +/- 1.8, P = 0.101) were not statistically different between the two groups.

Our results suggest that nailfold capillary morphology is altered in patients with PAPS, but these changes could not be correlated to impairment of functional parameters.