The Effect of Helicobacter pylori on the Presentation and Clinical Course of Coronavirus Disease 2019.

Reply: We have read with interest the letter by Papagni et al (1), which includes their praise and views on our article.

In our study, we based the diagnosis of Helicobacter pylori on the stool antigen test because it has a high specificity-sensitivity (2) and we believe that is the safest test in terms of transmission risk under extraordinary conditions. We consider that this approach is appropriate for exceptional cases, since every diagnostic procedure to be performed while diagnosing H pylori infection will put healthcare workers at greater risk. Eradication treatments were applied to our patients after the coronavirus disease 2019 (COVID-19) infection process finished.

H pylori has been reported to play a role in the pathogenesis of diseases by increasing the expression of angiotensin-converting enzyme-2 receptors in the gastrointestinal tract (3). We found no difference between patients with and without comorbid disease in terms of the course of the disease and the type of symptoms. Therefore, we think that the frequency of diarrhea and abdominal pain complaints is associated with H pylori.

We planned our study with 31 experimental subjects and 77 control subjects. Our data indicated that the probability of abdominal pain among H pylori negative cases is 2.6%. When the true probability of abdominal pain among H pylori positive cases is 19.4%, the null hypothesis is rejected with the probability (power) 0.69. On the other hand, our data also indicated that the probability of diarrhea among H pylori negative cases is 9.1%. When the true probability of diarrhea among H pylori positive cases is 32.3%, the null hypothesis is rejected with the probability (power) 0.73. The Type I error probability associated with this test of this null hypothesis is 0.05. We used a continuity-corrected chi-squared statistic or Fisher exact test to evaluate this null hypothesis.

This study is very valuable academically because it is the first study to investigate the relationship between the world's most common infectious disease and pandemic, and it pioneers studies in this field; however, as we mentioned in the article, there is a need for more comprehensive studies (where virulent elements of H pylori such as VacA can be examined one by one) in which more patients participated. Although our results show that diarrhea and abdominal pain are more common in H pylori positive patients during the course of COVID-19, it shows that the presence of H pylori does not affect the clinical outcome of COVID-19 infection. In conclusion, considering that the presence of H pylori does not affect the course of COVID-19, it is obvious that the presence of H pylori will not actually bring an additional burden to hospitals in this critical period.