AUTHOR=Huang Linlin , Zhu Wenbo , Ye Yan , Wu Xiaoping , Yan Qingran , Wang Zhiqing , Lin Yanwei , Chen Sheng TITLE=Association of Cytomegalovirus Infection With Anti-MDA5 Antibody-Positive Dermatomyositis: A Prospective Cohort Study JOURNAL=Frontiers in Medicine VOLUME=8 YEAR=2021 URL=https://www.frontiersin.org/journals/medicine/articles/10.3389/fmed.2021.740154 DOI=10.3389/fmed.2021.740154 ISSN=2296-858X ABSTRACT=

Objectives: To investigate whether cytomegalovirus (CMV) infection plays a role in the pathogenesis and prognosis of idiopathic inflammatory myopathy (IIM), particularly in anti-MDA5 antibody-positive (anti-MDA5⁺) dermatomyositis (DM).

Methods: A prospective cohort of 204 newly diagnosed IIM patients and 50 healthy individuals were enrolled in the study. CMV-IgM and CMV-IgG antibody concentrations and lymphocyte counts were analyzed. Differences in categorical data were compared using Fisher's exact test and the chi-square test. One-year survival rates were analyzed in MDA5⁺ DM patients with and without CMV infection.

Results: In IIM patients, the median CMV-IgM level was significantly higher than in healthy controls (6 U/mL vs. 0 U/mL, p < 0.05) as was the median CMV-IgG level (114 U/mL vs. 105 U/mL, p < 0.05). The percentage of recent CMV infections in the MDA5⁺ DM group was much higher than it was in the MDA5⁻ IIM group (19.1% vs. 7.0%, p = 0.009). MDA5⁺ DM patients with CMV DNA-emia had poorer 1 year survival than the CMV-DNA⁻ group (33.3% vs. 86.3%, p = 0.010). CMV-IgM-positive (CMV-IgM⁺) MDA5⁺ DM patients had lower CD4⁺ T cell counts (245.7 cells/μL vs. 420.5 cells/μL, p < 0.05) and CD19⁺ B cell counts (97.3 cells/μL vs. 240.6 cells/μL, p < 0.05).

Conclusion: The number of CMV infections was significantly higher in IIM patients, particularly in MDA5⁺ DM patients. Lower CD4⁺ T cells and CD19⁺ B cells were observed in CMV-IgM⁺ MDA5⁺ DM patients. CMV infection may have an important role in the pathogenesis and prognosis of MDA5⁺ DM by disrupting immunity.