Infectious Risk Mitigation in Patients with Multiple Sclerosis under Disease-Modifying Therapies - the Experience of a Collaborative Neurology-Infectious Diseases Approach

Background Multiple sclerosis treatment has changed in the last years with the emergence of new disease-modifying therapies (DMTs). Despite a better efficacy profile, these drugs raise concerns about infectious risk, which needs to be mitigated. Objective To analyze the results of a systematic collaborative approach between Neurology and Infectious Diseases (ID) Departments in the management of infectious risk and complications in MS patients treated with DMT. Methods Retrospective collection of MS patients' demographic and clinical data from clinical records of MS and ID outpatient clinics (2011-2017). Results We included 149 patients: most had evidence of previous contact with Herpesviridae, and half of them were not immune to hepatitis A and B viruses (HAV and HBV). Vaccines for HAV, HBV, and Streptococcus pneumoniae were administered in 91%, 78%, and 88% of non-immune patients, respectively. JC virus serology monitoring prevented natalizumab (NTZ) initiation or prompted its switch in 34/122 patients. Forty patients had latent tuberculosis, in which 88% were treated. Infectious events occurred in 33 patients, mostly mild urinary, respiratory, and herpes virus group infections. Only three patients required inpatient care. Conclusion Facing the expansion of the new DMT, we highlight the benefits of an interdisciplinary approach for safer use of the chosen treatment.