Incidence of persistent SARS-CoV-2 gut infection in patients with a history of COVID-19: Insights from endoscopic examination.
Level 4 - case-series / case-control
Prospective cross-sectional tissue study without an uninfected control group
PubMed 38188925 · doi:10.1055/a-2180-9872
What was done
Endoscopic mucosal biopsies were prospectively collected from patients with a history of COVID-19 undergoing upper gastrointestinal endoscopy (UGE) or lower gastrointestinal endoscopy (LGE). Immunohistochemistry was used to detect the presence of persistent SARS-CoV-2 nucleocapsid proteins and compare findings by clinical characteristics.
What was found
A total of 166 UGEs and 83 LGEs were analyzed. Positive immunostaining was significantly more frequent in UGE biopsies than in LGE biopsies (37.34% vs. 16.87%, P = 0.002). Positivity was significantly higher among smokers across the overall cohort and in both UGE and LGE subgroups (P < 0.001). Patients with diabetes also had higher positivity overall (P = 0.002) and in the UGE subgroup (P = 0.022), with a similar trend in the LGE subgroup (P = 0.055). No significant differences were seen based on number of prior infections, time since last infection, symptoms, or vaccination status.
Why it matters
These findings suggest that gastrointestinal mucosal tissue can act as a persistent viral reservoir for months after initial COVID-19 infection, with increased retention observed in smokers and individuals with diabetes.
Limits
The study relied on a convenience sample of patients clinically referred for endoscopy, introducing potential selection bias. Viral persistence was assessed only via immunohistochemistry for nucleocapsid protein, which does not confirm replication-competent virus. The abstract does not report a non-COVID-19 control group to exclude nonspecific background staining.
Cited by
- supports Replicating SARS-CoV-2 virus persists in the bodies of individuals months or years after recovery from acute infection, contributing to long COVID.