Session Information
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose:
To assess microvascular structure and function in patients with adult dermatomyositis (DM) and juvenile dermatomyositis (JDM), we have designed and built a mobile, high-resolution Nailfold Video Capillaroscopy (NFVC) installation for clinical use, and correlated the results with both laboratory and clinical measures in patients.
Methods:
We quantified nailfold capillary features in patients with DM (n=28) and JDM (n=17) with median age of 16.1 yrs (IQR 10.5 – 42.8) and median disease duration of 2.95 yrs (IQR 1.1 – 10.2) (74% females and 59% Caucasian) and healthy control subjects (n=18) with similar demographics. Capillary structural markers, including capillary density, tortuosity, interlimb distance, and functional markers, including local blood velocity in arterial (BVA) and venous (BVV) segments of capillaries, were measured. Left ring finger imaging of the nailfold area was performed with a motorized stereomicroscope (Leica M205C) equipped with a video camera (Hamamatsu ORCA-Flash4.0) at 25x overall magnification, providing 1 µm resolution and up to 100 Hz acquisition rate. Spearman rank correlation coefficients and p-values were calculated to determine correlations between NFVC markers and clinical data.
Results:
Capillary density (p<0.01), BVA (p < 0.05), and BVV (p < 0.05) are significantly lower in patients with DM and JDM than healthy subjects. Interlimb distance and capillary tortuosity were higher in DM or JDM than healthy controls (p<0.01). Capillary density and capillary interlimb distance (r= -0.65, p <0.001) correlated inversely, and BVA and BVV strongly correlated (r=0.95, p <0.001). There were no significant differences in any of these NFVC parameters between DM and JDM. NFVC markers correlated with myositis activity and damage measures and laboratory data from the combined DM/JDM group. Skin disease activity scores (DAS skin) negatively correlated with capillary density (r= -0.46, p <0.01) and positively with capillary interlimb distance (r=0.48, p<0.01). Extramuscular Myositis Disease Activity Assessment Tool (MDAAT) correlated with capillary tortuosity (r=0.35, p<0.05). Gastrointestinal (GI) MDAAT scores correlated negatively with BVA and BVV (r= -0.62 – -0.58, p<0.01), whereas manual muscle testing correlated with BVA and BVV (r=0.50-0.53, p<0.05). Among laboratory measures, ESR correlated with interlimb distances (r=0.41, p < 0.05) and negatively correlated with BVA and BVV (r= -0.47 – -0.48, p<0.05), and white blood cell count correlated with capillary tortuosity (r=0.55, p <0.001). Muscle enzymes and von Willebrand factor related antigen levels did not correlate with NFVC parameters. Among damage measures, MD global damage and muscular and skeletal damage in the Myositis Damage Index (MDI) correlated with capillary tortuosity (r=0.36 – 0.37, p<0.05), and GI MDI scores correlated negatively with BVA and BVV (r= -0.57 – -0.63, p<0.05).
Conclusion:
Structrual and functional NFVC markers correlate with disease activity and damage measures in muscle and extramuscular organs in children and adults with DM. Functional parameters of NFVC, including tortuosity and blood velocity, reveal new dimensions of the utility of NFVC in myositis assessment.
To cite this abstract in AMA style:
Prakash H, Song D, Lichy D, Rao P, Jain M, Shrader J, Miller FW, Schiffenbauer A, Gorbach A, Rider LG. Quantitative Nailfold Video Capillaroscopy Parameters Correlate with Dermatomyositis Activity and Damage [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/quantitative-nailfold-video-capillaroscopy-parameters-correlate-with-dermatomyositis-activity-and-damage/. Accessed .« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/quantitative-nailfold-video-capillaroscopy-parameters-correlate-with-dermatomyositis-activity-and-damage/