Study design Literature review. Objectives Describe the implications of post-COVID syndrome due to neurological sequelae including treatment and the differences that may exist between this group of patients and those who present these events not associated with COVID-19. Methods A non-systematic review of the literature was carried out in PubMed and Science Direct databases, using the keywords “Post-acute COVID-19 syndrome”; “Neurological complications”; “Neurologic Manifestations” “COVID-19″ and ”Rehabilitation“, as well as synonyms, which were combined with the operators ”AND“ and ”OR“. Results The COVID-19 viral caustive agent, SARS-CoV-2, has a high affinity for human angiotensin-converting enzyme 2 receptor on type II pneumocytes. This receptor is also expressed in neurons and glial cells. Based on the foregoing and other not so clear mechanisms, it is stated that SARS-CoV-2 has tropism for the nervous system, being evident through the neurological manifestations observed in patients with mild, moderate and severe phenotype of the disease such as anosmia, ageusia, headache, cerebrovascular accidents, Guillain-Barré syndrome, seizures, and encephalopathy. This can generate severe sequelae and even fatal outcomes in those affected. Conclusions Neurological complications caused by COVID-19 are frequent and represent a risk that compromises the functional capacity and the life of patients. The suspicion of these conditions, the strict control of metabolic alterations and cardiovascular risk factors, the effective and safe treatment of these entities, are a current challenge throughout the pandemic. The rehabilitation process in these patients is a challenge. This is due to the limitations generated by multi-organ damage, as well as risk of brain death.

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.

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disease affecting motor neurons (MNs). Although a small percentage of ALS has a familial origin, the vast majority of cases are sporadic in which genetic factors and environment interact with each other leading to disease onset in genetically predisposed individuals. In the current model of the disease, each individual has a determined genetic load, some degree of cell degeneration related to age and several risky environmental exposures. In this scenario, MN degeneration would occur when the sum of these factors reach a certain threshold. To date, an extensive list of environmental factors has been associated to ALS, including different categories, such as exposure to heavy metals and other toxicants, cyanotoxins or infectious agents. In addition, in recent years, lifestyle and other demographic parameters are gaining relevance in the genesis of the disease. Among them, physical activity, nutrition, body mass index, cardiovascular risk factors, autoimmune diseases and cancer are some of the conditions which have been related to the disease. In this review, we will discuss the potential mechanisms of environmental conditions in motor neuron degeneration. Understanding the role of each one of these factors as well as their interactions appears as a crucial step in order to develop new preventive, diagnostic and therapeutic approaches for ALS patients.