Is the Sars-CoV-2 virus a possible trigger agent for the development of achalasia?

BACKGROUNDPrevious studies have suggested that achalasia is an autoimmune disease whose probable causal agent is a neurotropic virus that chronically infects the myenteric plexus of the esophagus and, in a genetically susceptible host, induces the disease. The association between achalasia and coronaviruses has not been reported in the literature.AIMSTo evaluate the presence of the SARS-CoV-2 virus, the ACE2 expression, the tissue architecture, and immune response in the lower esophageal sphincter muscle (LESm) of achalasia patients who had SARS-CoV-2 (achalasia-COVID-19) infection before laparoscopic Heller myotomy (LHM) and compare the findings with type II achalasia patients and transplant donors (controls) without COVID-19.METHODSThe LESm of 7 achalasia-COVID-19 patients (diagnosed by PCR), ten achalasia patients, and ten controls without COVID-19 were included. The presence of the virus was evaluated by in situ PCR and immunohistochemistry. ACE2 receptor expression and effector CD4 T cell and regulatory subsets were determined by immunohistochemistry.RESULTSCoronavirus was detected in 6/7 patients-COVID-19. The SARS-CoV-2 was undetectable in the LESm of the achalasia patients and controls. The ACE2 receptor was expressed in all the patients and controls. One patient developed achalasia type II post-COVID-19. The percentage of Th22/Th17/Th1/pDCreg was higher in achalasia and achalasia-COVID-19 pre-HLM vs. controls. The Th2/Treg/Breg cell percentages were higher only in achalasia vs. controls.CONCLUSIONThe presence of the SARS-CoV2 and its receptor in the LESm of type II achalasia-COVID-19 patients but not in the controls suggests that it could affect the myenteric plexus. Unlike achalasia, patients-COVID-19 have an imbalance between effector CD4 T cells and the regulatory mechanisms.