Diarrhoea and preadmission antibiotic exposure in COVID-19: a retrospective cohort study of 1153 hospitalised patients.

OBJECTIVE: The aims of this study were to describe community antibiotic prescribing patterns in individuals hospitalised with COVID-19, and to determine the association between experiencing diarrhoea, stratified by preadmission exposure to antibiotics, and mortality risk in this cohort. DESIGN/METHODS: Retrospective study of the index presentations of 1153 adult patients with COVID-19, admitted between 1 March 2020 and 29 June 2020 in a South London NHS Trust. Data on patients' medical history (presence of diarrhoea, antibiotic use in the previous 14 days, comorbidities); demographics (age, ethnicity, and body mass index); and blood test results were extracted. Time to event modelling was used to determine the risk of mortality for patients with diarrhoea and/or exposure to antibiotics. RESULTS: 19.2% of the cohort reported diarrhoea on presentation; these patients tended to be younger, and were less likely to have recent exposure to antibiotics (unadjusted OR 0.64, 95% CI 0.42 to 0.97). 19.1% of the cohort had a course of antibiotics in the 2 weeks preceding admission; this was associated with dementia (unadjusted OR 2.92, 95% CI 1.14 to 7.49). After adjusting for confounders, neither diarrhoea nor recent antibiotic exposure was associated with increased mortality risk. However, the absence of diarrhoea in the presence of recent antibiotic exposure was associated with a 30% increased risk of mortality. CONCLUSION: Community antibiotic use in patients with COVID-19, prior to hospitalisation, is relatively common, and absence of diarrhoea in antibiotic-exposed patients may be associated with increased risk of mortality. However, it is unclear whether this represents a causal physiological relationship or residual confounding.

Regulation, risk and safety of Faecal Microbiota Transplant.

From its origins as a left-field, experimental, and even "maverick" intervention, faecal microbiota transplantation (FMT) is now a well-recognised, accepted, and potentially life-saving therapeutic strategy, for the management of recurrent Clostridiodes difficile infection (rCDI). It is being investigated as a treatment for a growing number of diseases including hepatic encephalopathy and eradication of antimicrobial resistant organisms, and the list of indications will likely expand in the future. There is no universally accepted definition of what FMT is, and its mechanism of action remains incompletely understood; this has likely contributed to the breadth of approaches to regulation depending on interpretation. In the UK FMT is considered a medicinal product, in North America, a biological product, whereas in parts of Europe, it is considered a human cell/tissue product. Regulation seeks to improve quality and safety, however, lack of standardisation creates confusion, and overly restrictive regulation may hamper widespread access and discourage research using FMT. FMT is generally considered safe, especially if rigorous donor screening and testing is conducted. Most short-term risks are associated with the delivery method (e.g. colonoscopy). Longer term risks are less well described but longitudinal follow-up of treated cohorts is in place to assess for this, and no signal towards harm has been found to date. Rarely it has been associated with adverse outcomes including the transmission of antibiotic resistant bacteria, and even death. It is vital patients undergoing FMT are well informed to the currently appreciated risks and benefits before proceeding.