Journal of Neurology

, Volume 266, Issue 1, pp 27–36 | Cite as

Infectious agents and amyotrophic lateral sclerosis: another piece of the puzzle of motor neuron degeneration

  • David Castanedo-Vazquez
  • Pilar Bosque-Varela
  • Arancha Sainz-Pelayo
  • Javier RianchoEmail author


Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disease affecting motor neurons (MN). This fatal disease is characterized by progressive muscle wasting and lacks an effective treatment. ALS pathogenesis has not been elucidated yet. In a small proportion of ALS patients, the disease has a familial origin, related to mutations in specific genes, which directly result in MN degeneration. By contrast, the vast majority of cases are though to be sporadic, in which genes and environment interact leading to disease in genetically predisposed individuals. Lately, the role of the environment has gained relevance in this field and an extensive list of environmental conditions have been postulated to be involved in ALS. Among them, infectious agents, particularly viruses, have been suggested to play an important role in the pathogenesis of the disease. These agents could act by interacting with some crucial pathways in MN degeneration, such as gene processing, oxidative stress or neuroinflammation. In this article, we will review the main studies about the involvement of microorganisms in ALS, subsequently discussing their potential pathogenic effect and integrating them as another piece in the puzzle of ALS pathogenesis.


ALS Amyotrophic lateral sclerosis Bacteria Fungi Infection Microorganisms Parasites Viruses 


Compliance with ethical standards

Conflicts of interest

All authors declare that they have no conflict of interests.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • David Castanedo-Vazquez
    • 1
  • Pilar Bosque-Varela
    • 2
  • Arancha Sainz-Pelayo
    • 3
  • Javier Riancho
    • 1
    • 4
    Email author
  1. 1.Service of NeurologyHospital Sierrallana-IDIVALTorrelavegaSpain
  2. 2.Service of NeurologyUniversity Hospital Marques de ValdecillaSantanderSpain
  3. 3.Service of NeurologyUniversity Hospital of BasurtoBilbaoSpain
  4. 4.CIBERNEDMadridSpain

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