Infections and spinal cord injury: Covid-19 and beyond

Spinal cord injuries cause not only a loss of mobility and sensibility, but also numerous chronic disorders such as: immunosuppression, higher rates of hypertension, neurogenic bladder, blood circulation impairments, and at T8 or above levels of injury, respiratory muscle weakness that can lead to breathing failure. All these conditions make chronic patients susceptible to infections due to a lowered immune system. The aim of this chapter is to analyze the clinical presentation of Covid-19 in patients with spinal cord injury. The authors pretend to make pause to understand if this emergent disease, which is deadly hitting our general population, behaves in the same way in these special patients, to understand if the spinal cord injury condition is acting as a risk factor for morbidity or not, and why. For this purpose, we want to explore the role that the immune system plays in causing infection in patients with spinal cord injury. Some spinal cord-injured patients develop a dysregulation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, which negatively affects all immune processes. Therefore, the combination of this situation with other locally impaired conditions provide the suitable environment for developing an infection, as it occurs in urinary tract infections, the most frequent infection in these patients, because of the presence of a neurogenic bladder and the use of catheters to facilitate its voiding; or in pulmonary infections, the severest ones, because of the respiratory muscle weakness, dysphagia disorders, pulmonary edema, and the use of ventilators to assist with breathing. The physiopathology of these infections helps us to understand its appropriate diagnosis, treatment, and methods of prevention. Most of the published studies show a tendency of milder initial symptoms and a less severe evolution of the Covid-19 disease in spinal cord-injured patients, but currently further validation is needed to support or reject it. The altered immune response could play a critical role in the clinical presentation of these patients. Close observation of neurofunctional outcomes, especially with the help of the International Standards for Neurological Classification of the Spinal Cord Injury (ISNCSCI) Worksheet, is needed to conclude if this infection produces sensory and motor deficits in these patients. Telemedicine has demonstrated to be a useful and effective tool to provide access to medical healthcare to these chronically affected patients, especially under pandemic restriction.