Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
In systemic sclerosis, a scleroderma pattern on nailfold videocapillaroscopy (NVC) (SSc) is well recognized. In idiopathic inflammatory myopathies (IIM), a scleroderma-like pattern, including giant-ramified capillaries, has been proposed. The aim of our study was to describe nailfold capillary abnormalities in IIM subsetted using newly proposed integrative criteria [1,2].
We studied IIM subjects in the Canadian Inflammatory Myopathy Study (CIMS), a cohort of subjects with early onset disease followed prospectively. NVC images were acquired using the DS MEDICA Videocap (X200 magnification). The nailfolds of the second, third, fourth and fifth fingers of both hands were photographed and scored by an experienced rheumatologist. Microhemorrhages, giant capillaries, ectasias and ramified capillaries were scored using a standardized semi-quantitative scale (0 = no, 1 = ≤33%, 2= 33–66%, and 3 = ≥66% abnormalities per linear millimeter). Capillary density was scored both semi-quantitatively (0 if ≥7, 1 if 4–6, or 2 if ≤3 capillaries/mm) and quantitatively (mean number of capillaries/mm). Each NVC parameter, as well as disorganization and giant-ramified capillaries, were also scored as present or absent. Finally, the proportion of subjects with scleroderma-like, scleroderma (SSc), non-specific, and normal patterns were compared.
38 IIM subjects were included: 18 with DM (of which 9 had myositis specific antibodies and 9 were seronegative) and 20 with OM (of which 8 had anti-synthetase syndrome). Baseline characteristics of the subjects and NVC features and patterns are presented in Tables 1-3. Capillary density was lower than normal in both DM (mean 5.5/mm) and OM (mean 6.1/mm). Giant-ramified capillaries were present in 22.2 % of DM and 25% of OM subjects. SSc-like pattern was more common in DM (50%) than OM (25%), whereas active- or late-SSc pattern was more common in OM than DM (25% vs 5.6%).
This is the first study of NVC using integrative criteria for IIM. We found differences in NVC features and patterns between DM and OM subsets. NVC may be an additional diagnostic tool in IIM. A larger study is ongoing to confirm these findings.
Benveniste et al. Curr Opin Neurol 2016;29(5):662-73.
Allenbach et al. Neuropathol Appl Neurobiol 2017;43(1):62-81.