ABSTRACT
Introduction: Increased inflammatory cytokines has been observed in COVID-19 patients and there is evidence showing an alteration in gut-microbiota composition. SARS-CoV-2 can cause gastrointestinal symptoms, such as diarrhea. Evidence of an altered gut-microbiota composition and cytokines levels in COVID-19 diarrhea patients is lacking. Objectives: To compare serum cytokine levels and gut microbiota between COVID-19 diarrhea (D-COVID- 19) and non-diarrhea (NonD-COVID-19) patients and non- COVID-19 controls (HC). Material and methods: We included 143 hospitalized COVID-19 patients (positive quantitative reverse transcription PCR) in a single University Hospital, and 53 ambulatory HC (negative rapid serological test) were included. Blood and stool samples were collected at hospital admission in COVID-19 patients and at the time of HC recruitment. 27- pro and anti-inflammatory cytokines (Bio-Plex Pro™, Bio- Rad) were measured. Gut microbiota composition and diversity profiles were characterized by sequencing the 16S rRNA gene V3-V4 region amplified using DNA extracted from stool samples. Bioinformatics analysis was performed with QIIME2 software. First, we compare cytokine levels between COVID- 19 and HC and then COVID-19 with and without diarrhea. All comparisons were adjusted for age, sex, and BMI with linear regression. Results: The mean age in COVID-19 patients was 54 +/- 15 years (F=50%) and 52 +/- 8 (F=62%) for HC. Diarrhea was present in 19 (13.29%) of COVID-19 patients. COVID-19 patients had significative higher levels of: IL- 1ra, IL-2, IL-6, IL-7, IL-8, IL-13, IP-10 and PDGF-bb. Significant lower values of: IL-9, FGF -basic, MIP-1β, TNF-α were observed in D-COVID-19 compared to NonD-COVID-19. COVID-19 patients had a significant reduction of bacterial species (p=0.0001), and diversity and complexity of the bacterial community (Shannon's index) (p=0.0001) compared to the HC. There was no difference between D-COVID-19 and NonD-COVID-19. There were also changes in the composition of the microbiota associated with COVID-19. At the phylum level, COVID-19 patients showed a significant decrease in Actinobacteria and Firmicutes, and an increase in Bacteroidetes. At species level, an increase of 4 species of the genus Bacteroides was observed in COVID-19 patients. 31 very diverse bacterial species were found, all decreased in D-COVID-19. Conclusions: An alteration in serum cytokine levels was observed between COVID-19 and HC. D-COVID-19 had a decrease in some proinflammatory cytokines. A significant decrease in richness and species diversity of gutmicrobiota was observed in COVID-19 patients compared to HC, but no significant differences were observed between D-COVID-19 and NonD-COVID-19. However, in D-COVID- 19, a decrease in some bacterial species was observed.(Table Presented)(Figure Presented)
ABSTRACT
INTRODUCTION: There is evidence that the gut microbiota and its relationship with the immune system could be involved in the pathogenesis of COVID-19. SARS-CoV-2 can cause gastrointestinal symptoms during the early phases of the disease. Intestinal dysfunction induces changes in intestinal microbes, and an increase in inflammatory cytokines. Therefore, microbiota modulation could play a role in COVID-19 treatment. Tannins have been shown to work as prebiotics on the gastrointestinal microbiota. In particular, quebracho and chestnut tannins have shown to regulate the immune response and decrease in vitro-cytokines production, through microbiota fermentation-secondary metabolites, such as quercetin and SCFAs. OBJECTIVE: To evaluate the efficacy and the effect on cytokine levels of a tannin specific natural extract in COVID-19 patients. MATERIAL AND METHODS: This prospective, doubleblind, and randomized study was approved by the Hospital de Clínicas, José de San Martín (Buenos Aires, Argentina). Blood and stool samples were collected at baseline (Day 0) and after treatment (Day 14) during July-October 2020, with final follow-up in November 2020. We randomly assigned 124 RT-PCR confirmed COVID-19 cases (>18 years) to receive oral dry extracts of quebracho and chestnut tannins (240 mg) and B12 vitamin (0.72 μg) or placebo, twice daily for 14 days as adjunct treatment to their standard of care management. 27-pro and anti-inflammatory cytokines were measured on day 0 and 14 (Bio-Plex Pro™, Bio-Rad). Final enrollment of 140 patients with matched fecal microbiome characterization (16S, WGS and metabolites) is expected. RESULTS. Of 124 patients who were randomized (mean age 55+/-15, 63 [50.81%] male), 121 (97.58%) completed the trial. No adverse events were observed in the tannin group. Patients presenting with diarrhea (13%) had a trend to have elevated blood MIP-1α levels, which were significantly reduced by tannin treatment (Table 1). At baseline, higher levels of MIP-1α were also associated with diagnosis of pneumonia (Fig. 1), which was maintained after adjusting for confounders (age, sex, diabetes;p=0.04). Moreover, at baseline there was a positive correlation between MIP-1 α and IL-1ra, IL-2, MIP-1b and TNF-α, with all of these cytokines decreasing mostly with tannin treatment. CONCLUSION: To our knowledge, this clinical trial represents the first study to target the gut microbiome in hospitalized COVID-19 patients. Oral tannins as adjunct treatment with standard-of-care management of these patients significantly reduced proinflammatory cytokine levels that are generally associated with poor predictive outcomes, i.e. pneumonia and diarrhea. Further, our prospective studies will determine which microbiome-mediated mechanisms may attenuate the cytokine storm that is evident in COVID-19 disease pathogenesis. (Table presented) (Figure presented)
ABSTRACT
This retrospective descriptive study analyzes the clinical and epidemiological characteristics, the disease evolution and its association with laboratory markers of poor prognosis of the first 100 patients with COVID-19 admitted to internal medicine wards at the Hospital de Clínicas José de San Martín, University of Buenos Aires. Thirty-one patients were nursing home residents, the most common clinical manifestations were fever, cough and odynophagia. Regarding comorbidities, obesity was the most frequent one and hypertension was the most prevalent in patients with pneumonia. The most important predictors of mortality were age and pneumonia. Patients older than 70 years had higher acute phase reactants showing an exaggerated inflammatory response. Mortality was high (13%), compared to most reports (5%), probably because of the advanced age of our population and the unfavorable clinical conditions they presented at admission. Se analiza, en un estudio descriptivo retrospectivo, las características clínicas y epidemiológicas, la evolución de la enfermedad y su asociación con los marcadores del laboratorio de mal pronóstico, en los primeros 100 pacientes internados en clínica médica con COVID-19 en el Hospital de Clínicas José de San Martín de la Universidad de Buenos Aires. El 31% de los pacientes provenían de geriátricos, las manifestaciones clínicas más comunes fueron fiebre, tos y odinofagia. En relación a las comorbilidades, la obesidad fue la más frecuente y la hipertensión arterial la más prevalente en los pacientes con neumonía. La edad y la presencia de neumonía fueron los predictores más importantes de mortalidad. Los pacientes mayores de 70 años presentaron reactantes de fase aguda más elevados mostrando una respuesta inflamatoria exagerada. La mortalidad fue elevada (13%), en comparación con la mayoría de las comunicaciones (5%), probablemente como consecuencia de la edad avanzada de nuestra población y las condiciones clínicas desfavorables que presentaron a su ingreso.