Infections in patients with multiple sclerosis treated with disease-modifying therapies: A comparative risk assessment cohort study

  • Mohammad Reza Fattahi Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Amir Valizadeh Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Amirreza Azimi Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Abdorreza Naser Moghadasi Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Moein Ghasemi Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Samira Navardi Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Rozita Doosti Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
  • Zahra Hemmati Department of Stroke, Epsom and St Helier University Hospitals, Epsom, KT18 7EG, UK
  • Ali Zare-Dehnavi Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Arad Iranmehr Neurosurgery Department, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Sara Hamtaei-Gashti Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
  • Mohammad Ali Sahraian Multiple Sclerosis Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
Keywords: Multiple Sclerosis; Infections; Interferons; Fingolimod; Rituximab; Azathioprine

Abstract

Background: The major treatment regimens for multiple sclerosis (MS) are disease-modifying therapies (DMTs). Fungal, viral, and bacterial infections are common complications of these drugs. Also, MS itself is an immune-related chronic disease that can compromise their subjects to infections. Therefore, MS can be a risk factor for infectious complications.

Methods: This paper is a retrospective cohort study conducted from February 2020 to January 2022 using prospectively collected data from every patient registered at the Multiple Sclerosis Referral Research Center in Tehran, Iran. We inducted patients with MS who were diagnosed based on McDonald's criteria and exposed to DMTs for at least 6 months prior to this study. Being under 18 years of age, diagnosis change during the study, and mortality were the exclusion criteria of this study.

Results: We inducted a total of 979 patients into this study. Rituximab and natalizumab were associated with a higher risk of urinary tract infection (UTI) and bacterial vaginitis. Moreover, rituximab, glatiramer acetate, and dimethyl fumarate were associated with HSV-associated ulceration. None of the investigated DMTs were associated with an altered risk of COVID-19.

Conclusion: The use of DMTs can result in an increased risk of infections in patients. The selection of these DMTs should be based on their efficacy and risk of complications. Healthcare providers should familiarize themselves with these complications to select the appropriate DMTs with the highest efficacy.

 

Published
2026-01-04
Section
Articles