Mechanistic insights into bone remodelling dysregulation by human viral pathogens.

Bone-related diseases (osteopathologies) associated with human virus infections have increased around the globe. Recent findings have highlighted the intricate interplay between viral infection, the host immune system and the bone remodelling process. Viral infections can disrupt bone homeostasis, contributing to conditions such as arthritis and soft tissue calcifications. Osteopathologies can occur after arbovirus infections such as chikungunya virus, dengue virus and Zika virus, as well as respiratory viruses, such as severe acute respiratory syndrome coronavirus 2 and enteroviruses such as Coxsackievirus B. Here we explore how human viruses dysregulate bone homeostasis, detailing viral factors, molecular mechanisms, host immune response changes and bone remodelling that ultimately result in osteopathologies. We highlight model systems and technologies to advance mechanistic understanding of viral-mediated bone alterations. Finally, we propose potential prophylactic and therapeutic strategies, introduce 'osteovirology' as a research field highlighting the underestimated roles of viruses in bone-related diseases, and discuss research avenues for further investigation.

Breakthrough SARS-CoV-2 Infections in Patients With Immune-Mediated Disease Undergoing B Cell-Depleting Therapy: A Retrospective Cohort Analysis.

OBJECTIVE: Patients with immune-mediated inflammatory diseases (IMIDs) receiving B cell-depleting therapy (BCDT) are among the most vulnerable to severe COVID-19, as well as the most likely to suboptimally respond to SARS-CoV-2 vaccines. However, little is known about the frequency or severity of breakthrough infection in this population. We retrospectively analyzed a large group of vaccinated IMID patients undergoing BCDT in order to identify breakthrough COVID-19 infections and assess their outcomes. METHODS: In this retrospective cohort study, the pharmacy records and COVID-19 registry at the Cleveland Clinic were searched using specific International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes to identify IMIDs patients who 1) received treatment with BCDT, 2) were vaccinated against SARS-CoV-2, and 3) experienced breakthrough infections. Each electronic medical record was reviewed to extract clinical data and outcomes. Univariate and multivariable logistic/proportional odds regression models were used to examine the risk factors for severe outcomes. RESULTS: Of 1,696 IMID patients receiving BCDT, 74 developed breakthrough COVID-19 prior to December 16, 2021. Outcomes were severe, with 29 patients hospitalized (39.2%), 11 patients requiring critical care (14.9%), and 6 deaths (8.1%). Outpatient anti-SARS-CoV-2 monoclonal antibodies were used to treat 21 patients, with 1 hospitalization and no deaths. A comparator analysis examining 1,437 unvaccinated IMID patients receiving BCDT over the same time period identified 57 COVID-19 cases (4.0%), with 28 requiring hospitalization (49.1%), including 7 deaths (12.3%). CONCLUSION: IMID patients receiving BCDT regardless of vaccine status appear to be vulnerable to infection with SARS-CoV-2, and use of BCDT is frequently associated with severe outcomes. Outpatient use of anti-SARS-CoV-2 monoclonal antibody therapy appears to be associated with enhanced clinical outcomes.

The Risk of Progressive Multifocal Leukoencephalopathy in the Biologic Era: Prevention and Management.

Progressive multifocal leukoencephalopathy (PML) is a rare, typically fatal, demyelinating central nervous system infection caused by reactivation of the John Cunningham virus that generally occurs in immunosuppressed patients. With an evolving understanding of a greater clinical heterogeneity of PML and significant implications for therapy, PML should be considered in the differential diagnosis of neurologic presentations of rheumatic diseases. Increased awareness of PML among rheumatologists is required, as earlier diagnosis and restoration of immune function may improve the otherwise grim prognosis associated with PML.