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.