A new article published in Gut stated that the gut microbiome, may influence the severity of COVID-19 as well as the magnitude of the immune system response to infection.  

 

The study entailed two-hospital cohort study, wherein blood, stool and patient records were obtained from 100 patients with laboratory-confirmed SARS-CoV-2 infection. Serial stool samples were collected from 27 of the 100 patients up to 30 days after clearance of SARS-CoV-2. Gut microbiome compositions were characterized. Concentrations of inflammatory cytokines and blood markers were measured from plasma.

 

The results showed that the gut microbiome composition was significantly altered in patients with COVID-19, irrespective of whether patients had received medication. In addition, several gut commensals with known immunomodulatory potential, such as – Faecalibacterium prausnitzii, Eubacterium rectale and bifidobacteria were underrepresented in patients, and remained low in samples collected up to 30 days after disease resolution. This inconsistency in composition exhibited stratification with disease severity concordant with elevated concentrations of inflammatory cytokines and blood markers such as C reactive protein, lactate dehydrogenase, aspartate aminotransferase and gamma-glutamyl transferase.

 

It was concluded that the gut microbiome is involved in the magnitude of COVID-19 severity, which was speculated to occur through modulation of host immune responses. Furthermore, the gut microbiota dysbiosis after disease resolution could contribute to persistent symptoms.

Source: Gut microbiota composition reflects disease severity and dysfunctional immune responses in patients with COVID-19. Gut 2021;70:698-706.