Pseudomembranous Colitis in a Coronavirus Disease 19 positive patient : not a simple issue. (preprint)

Since its emergence, Coronavirus Disease (Covid-19) rapidly spread worldwide and was responsible for a global pandemic. Although it was initially considered a respiratory disease, recent studies have evidenced that Covid-19 had serious systemic adverse effects involving major organs, including those of the digestive system. Histological lesions associated with these manifestations have rarely been reported. We, herein, present a singular case of pseudomembranous colitis (PMC), proven histologically, in a 73-year-old Covid-19 positive female patient. We aim to study the clinico-pathological characteristics of this association. A 73-year-old Covid positive patient was intubated and put on intravenous antibiotherapy after the deterioration of her respiratory function. Ten days after admission, the patient presented abdominal distension and melena. An abdominal tomography scan showed a left mesenteric infarction related to a thrombosis at the origin of the left mesenteric artery. A left hemicolectomy was performed in emergency. Macroscopic examination of the hemicolectomy specimen showed an edematous colonic mucosa, with multiple ulcerations covered by a whitish necrotic coating reminiscent of false membranes. Histological examination confirmed the diagnosis of PMC. The patient presented a septic shock and died six days after the operation. The PMC could have resulted from the use of antibiotics. However, the direct involvement of Covid-19 in the occurrence of this PMC cannot be excluded. Further studies are needed to evaluate the direct correlation between Covid-19 and PMC.

Clostridioides difficile infection in coronavirus disease 2019 (COVID-19): an underestimated problem?

INTRODUCTION: The use of antibiotics and possibility of microbiota disruption during the coronavirus disease 2019 (COVID­19) pandemic have raised questions about the incidence of Clostridioides difficile infection (CDI). OBJECTIVES: This study aimed to assess the frequency of and risk factors for CDI in patients with COVID­19. PATIENTS AND METHODS: We conducted a retrospective, single­center evaluation study on the frequency of and risk factors for CDI in patients with COVID­19 and in the prepandemic era. The analysis included 441 patients with severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) infection and 2961 pa­ tients hospitalized before the pandemic. RESULTS: A significant increase in the incidence of CDI was noted during the COVID­19 pandemic compared with the prepandemic period: 10.9% versus 2.6%, P <0.001. Risk factors for CDI in patients with COVID­19 included: age, length of hospital stay, occurrence of diarrhea during hospitalization, use of antibiotics other than azithromycin, and coexistence of nervous system disease or chronic kidney disease-all of these factos had a weak association with CDI development. The multivariable logistic regression model indicated other unassessed variables that had an impact on the CDI incidence rate. CONCLUSIONS: We observed a higher incidence of CDI in patients with COVID­19. Antibiotic therapy was a relevant risk factor for CDI, although its effect was weak. Other drugs used during the pandemic were not found to have an impact on disease development. Possible causes of CDI may include fecal microbiota disruption by SARS­CoV­2 infection, but further research is needed to validate this hypothesis.

Necrotising Vasculitis in Covid-19: watch out for bowel perforation (preprint)

Introduction: SARS-Cov-2 infection can be asymptomatic, greatly impair respiratory function and, sometimes, affect other organs. Gastro-enteric involvement seems to be not so rare and many patients suffered for abdominal pain, anorexia, nausea and vomiting, diarrhoea or jaundice. Case presentation: Here we report a case of a Covid-19 patient who developed a right colon perforation due to a pseudomembranous colitis without Clostridium Difficile toxins finding associated to a necrotising vasculitis. In this patient a PCR test performed on gastric fluid showed SARS-CoV-2 enteric replication. Discussion: Necrotizing vasculitis is an anatomopathological typical findings in Covid-19. It has been documented in several organs and tissues. In our case, evident foci of necrotizing vasculitis with intravascular obliteration by fibrin thrombi with macrophagic cells infiltration are anatomopathological findings of a CD toxins free pseudomembranous colitis leading to bowel perforation. Conclusions: Bowel perforation due to necrotizing vasculitis leading to pseudomembranous colitis could be a SARS-Cov-2 related clinical finding.

Development and implementation of a customised rapid syndromic diagnostic test for severe pneumonia (preprint)

Background The diagnosis of infectious diseases has been hampered by reliance on microbial culture. Cultures take several days to return a result and organisms frequently fail to grow. In critically ill patients this leads to the use of empiric, broad-spectrum antimicrobials and mitigates against stewardship. Methods Single ICU observational cohort study with contemporaneous comparator group. We developed and implemented a TaqMan array card (TAC) covering 52 respiratory pathogens in ventilated patients undergoing bronchoscopic investigation for suspected pneumonia. The time to result was compared against conventional culture, and sensitivity compared to conventional microbiology and metagenomic sequencing. We observed the clinician decisions in response to array results, comparing antibiotic free days (AFD) between the study cohort and comparator group. Findings 95 patients were enrolled with 71 forming the comparator group. TAC returned results 61 hours (IQR 42-90) faster than culture. The test had an overall sensitivity of 93% (95% CI 88-97%) compared to a combined standard of conventional culture and metagenomic sequencing, with 100% sensitivity for most individual organisms. In 54% of cases the TAC results altered clinical management, with 62% of changes leading to de-escalation, 30% to an increase in spectrum, and investigations for alternative diagnoses in 9%. There was a significant difference in the distribution of AFDs with more AFDs in the TAC group (p=0.02). Interpretation Implementation of a customised syndromic diagnostic for pneumonia led to faster results, with high sensitivity and measurable impact on clinical decision making. Funding Addenbrookes Charitable Trust, Wellcome Trust and Cambridge NIHR BRC