Meta-analysis of the demographic and prognostic significance of gastrointestinal symptoms in COVID-19 patients.

Background and Aim: To evaluate the demographic and prognostic significance of gastrointestinal (GI) symptoms in patients with coronavirus disease 2019 (COVID-19). Methods: A systematic search of electronic information sources was conducted. Combined overall effect sizes were calculated using random-effects models for baseline demographic factors and outcomes including mortality, intensive care unit (ICU) admission, and length of hospital stay. Results: Twenty-four comparative observational studies reporting a total of 51 522 COVID-19 patients with (n = 6544) or without (n = 44 978) GI symptoms were identified. The patients with GI symptoms were of comparable age (mean difference [MD]: 0.25, 95% confidence interval [CI] -2.42 to 2.92, P = 0.86), rate of pre-existing hypertension (odds ratio [OR]: 1.11, 95% CI 0.86-1.42, P = 0.42), diabetes mellitus (OR: 1.14, 95% CI 0.91-1.44, P = 0.26), and coronary artery disease (OR: 1.00, 95% CI 0.86-1.16, P = 0.98) compared with those without GI symptoms. However, there were significantly more male patients in the GI symptoms group (OR: 0.85, 95% CI 0.75-0.95, P = 0.005). The presence of GI symptoms was associated with similar risk of mortality (OR: 0.73; 95% CI 0.47-1.13, P = 0.16), ICU admission (OR: 1.15; 95% CI 0.67-1.96, P = 0.62), and length of hospital stay (MD: 0.43; 95% CI -0.73 to 1.60, P = 0.47) when compared with their absence. Conclusion: Meta-analysis of the best possible available evidence demonstrated that GI symptoms in COVID-19 patients do not seem to affect patients with any specific demographic patterns and may not have any important prognostic significance. Although no randomized studies can be conducted on this topic, future high-quality studies can provide stronger evidence to further understand the impact of GI symptoms on outcomes of COVID-19 patients.

Multi-modality detection of SARS-CoV-2 in faecal donor samples for transplantation and in asymptomatic emergency surgical admissions.

Background: Faecal transplantation is an evidence-based treatment for Clostridioides difficile. Patients infected with SARS-CoV-2 have been shown to shed the virus in stool for up to 33 days, well beyond the average clearance time for upper respiratory tract shedding. We carried out an analytical and clinical validation of reverse-transcriptase quantitative (RT-qPCR) as well as LAMP, LamPORE and droplet digital PCR in the detection of SARS-CoV-2 RNA in stool from donated samples for faecal microbiota transplantation (FMT), spiked samples and asymptomatic inpatients in an acute surgical unit.  Methods: Killed SARS-CoV-2 viral lysate and extracted RNA was spiked into donor stool & FMT and a linear dilution series from 10 -1 to 10 -5 and tested via RT-qPCR, LAMP, LamPORE and ddPCR against SARS-CoV-2. Patients admitted to the critical care unit with symptomatic SARS-CoV-2 and sequential asymptomatic patients from acute presentation to an acute surgical unit were also tested. Results: In a linear dilution series, detection of the lowest dilution series was found to be 8 copies per microlitre of sample. Spiked lysate samples down to 10 -2 dilution were detected in FMT samples using RTQPCR, LamPORE and ddPCR and down to 10 -1 with LAMP. In symptomatic patients 5/12 had detectable SARS-CoV-2 in stool via RT-qPCR and 6/12 via LamPORE, and in 1/97 asymptomatic patients via RT-qPCR. Conclusion: RT-qPCR can be detected in FMT donor samples using RT-qPCR, LamPORE and ddPCR to low levels using validated pathways. As previously demonstrated, nearly half of symptomatic and less than one percent of asymptomatic patients had detectable SARS-CoV-2 in stool.

A novel tool for noninvasive diagnosis and tracking of patients with inflammatory bowel disease.

BACKGROUND: The pathogenesis of inflammatory bowel disease (IBD) involves the role of bacteria. These bacteria ferment nonstarch polysaccharides in the colon producing a fermentation profile that through altered gut permeability can be traced in urine. We proposed to track the resultant volatile organic compounds or gases that emanate from urine using noninvasive real-time tools, specifically by electronic nose and Field Asymmetric Ion Mobility Spectrometer (FAIMS) instruments. The aim of this study was to determine the utility of electronic nose and FAIMS instruments to detect and track the fermentation profile of patients with IBD. METHODS: Sixty-two individuals were recruited, 48 individuals with IBD (24 with Crohn's disease and ulcerative colitis, respectively) and 14 controls. The disease activity was recorded, and urine samples were collected. The headspace (the air above the sample) was analyzed using the electronic nose and FAIMS instruments. RESULTS: Electronic nose data analysis was conducted through (1) Principal Component Analysis (data were analyzed together without previous categorization); and (2) Discriminant Function Analysis (samples were precategorized [clinical groups]). The FAIMS data were processed by Fisher's Discriminant Analysis (precategorized [clinical groups]). Both technologies consistently showed the ability to separate those with IBD and controls with a >75% accuracy; P < 0.001. In a smaller subgroup (n = 24), we also demonstrated that the electronic nose and FAIMS instruments can distinguish between active disease and those in remission. CONCLUSIONS: The fermentation profile or fermentome is disparate in those with IBD compared with controls--a reflection of the bacterial diversity in health and disease. This profile also changes (and was tracked) as the disease is induced into remission. Thus, the electronic nose and FAIMS instruments offer the potential of a noninvasive real-time diagnostic tool for point of care clinical use.

Assessment of pulmonary neutrophilic inflammation in emphysema by quantitative positron emission tomography.

RATIONALE: Neutrophilic inflammation is understood to be of pathogenetic importance in chronic obstructive pulmonary disease (COPD) and may be quantified using 18-fluorodeoxyglucose positron emission tomography-computed tomography ((18)FDG PET-CT) as a noninvasive, spatially informative biomarker. OBJECTIVES: To assess the potential usefulness of (18)FDG PET-CT as a surrogate measure of pulmonary neutrophilic inflammation in patients with usual COPD and α(1)-antitrypsin deficiency (AATD). METHODS: (18)FDG PET-CT imaging was performed in 10 patients with usual COPD, 10 patients with AATD, and 10 healthy control subjects. Pulmonary (18)FDG uptake was estimated by three-dimensional Patlak graphical analysis as an indicator of pulmonary neutrophilic glycolytic activity. Patients with AATD were treated with 12 weekly intravenous infusions of AAT augmentation therapy before repeat imaging. (18)FDG uptake, lung physiology, lung density, and systemic markers of inflammation were compared for all groups at baseline and, in patients with AATD, at baseline and on treatment. MEASUREMENTS AND MAIN RESULTS: (18)FDG uptake in the upper lung of patients with usual COPD was greater compared with the healthy control group (P = 0.009) and correlated with measures of disease severity (FEV(1)% predicted, r = -0.848, P = 0.001; FEV(1)/FVC, r = -0.918, P < 0.001; Kco% predicted, r = -0.624, P = 0.027; 15th percentile point, r = -0.709, P = 0.011). No significant difference was observed between measurements at baseline and on treatment in patients with AATD. CONCLUSIONS: Quantitative (18)FDG PET-CT has a potential role as an imaging biomarker in mechanistic and interventional studies in patients with usual COPD. The data support previous evidence of distinct functional characteristics of neutrophils in COPD. Clinical trial registered with https://eudract.ema.europa.eu/index.html (EudraCT 2007-004869-18).