Bedside Assessment of Immune Function in Patients With Covid-19

Covid-19 is a global pandemic causing unprecedented morbidity and mortality in the general population. It appears to have a greater effect on the elderly or those with underlying health problems but is not exclusively confined to these groups. As people age, particularly toward the end of their lives, the response of the immune system begins to drop away, an occurrence known as immunosenescence. It is known that there exist a group of people that do not respond to immune stimulation in a normal way but who may to observers be considered fit and healthy. The leukocyte immune test (LIT) relies upon the supramaximal stimulation of white cells outside of the body to determine their reactiveness when stimulated. It is intended to study patients admitted to Barts Health with diagnosed Covid-19. 4 ml blood will be taken of which 10microlitres will be used for the LIT. The remainder will be used for measurement of antibody levels previously associated with poor outcome following cardiac surgery. The patients will be followed up to see the proportion that progress to requirement for critical care, advanced ventilatory support, renal failure and in-hospital mortality. If a link can be established between a poor outcome following admission to hospital with Covid-19 and the immune response on admission, as predicted by means of the LIT, then it may enable better formulation of potential treatment strategies. Being able to measure at point of admission the responsiveness of someone's immune system may mean that treatment strategies such as the administration of passive immunization either via convalescent plasma or gammaglobulin will be better guided. If the LIT proves able to identify those people at risk of severe disease it may be able to identify individuals amongst healthcare workers that may benefit from passive immunisation or avoidance of high-risk exposure to Covid-19.