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Background Despite advances in the understanding and diagnosis of Clostridioides difficile infection (CDI), clinical distinction within the colonization–infection continuum remains an unmet need. Methods By measuring stool cytokines and antitoxin antibodies in well-characterized cohorts of CDI (diarrhea, nucleic acid amplification test [NAAT] positive), non-CDI diarrhea (NCD; diarrhea, NAAT negative), asymptomatic carriers (ASC; no diarrhea, NAAT positive) and hospital controls (CON; no diarrhea, NAAT negative), we aim to discover novel biological markers to distinguish between these cohorts. We also explore the relationship of these stool cytokines and antitoxin antibody with stool toxin concentrations and disease severity. Results Stool interleukin (IL) 1β, stool immunoglobulin A (IgA), and immunoglobulin G (IgG) anti–toxin A had higher (P <.0001) concentrations in CDI (n = 120) vs ASC (n = 43), whereas toxins A, B, and fecal calprotectin did not. Areas under the receiver operating characteristic curve (ROC-AUCs) for IL-1β, IgA, and IgG anti–toxin A were 0.88, 0.83, and 0.83, respectively. A multipredictor model including IL-1β and IgA anti–toxin A achieved an ROC-AUC of 0.93. Stool IL-1β concentrations were higher in CDI compared to NCD (n = 75) (P <.0001) and NCD + ASC+ CON (CON, n = 75) (P <.0001), with ROC-AUCs of 0.83 and 0.86, respectively. Stool IL-1β had positive correlations with toxins A (ρA = +0.55) and B (ρB = +0.49) in CDI (P <.0001) but not in ASC (P >.05). Conclusions Stool concentrations of the inflammasome pathway, proinflammatory cytokine IL-1β, can accurately differentiate CDI from asymptomatic carriage and NCD, making it a promising biomarker for CDI diagnosis. Significant positive correlations exist between stool toxins and stool IL-1β in CDI but not in asymptomatic carriers. [ABSTRACT FROM AUTHOR]

Background Stool toxin concentrations may impact Clostridioides difficile infection (CDI) severity and outcomes. We correlated fecal C difficile toxin concentrations, measured by an ultrasensitive and quantitative assay, with CDI baseline severity, attributable outcomes, and recurrence. Methods We enrolled 615 hospitalized adults (≥18 years) with CDI (acute diarrhea, positive stool nucleic acid amplification testing, and decision to treat). Baseline stool toxin A and B concentrations were measured by single molecule array. Subjects were classified by baseline CDI severity (4 scoring methods) and outcomes within 40 days (death, intensive care unit stay, colectomy, and recurrence). Results Among 615 patients (median, 68.0 years), in all scoring systems, subjects with severe baseline disease had higher stool toxin A+B concentrations than those without (P <.01). Nineteen subjects (3.1%) had a severe outcome primarily attributed to CDI (group 1). This group had higher median toxin A+B (14 303 pg/mL [interquartile range, 416.0, 141 967]) than subjects in whom CDI only contributed to the outcome (group 2, 163.2 pg/mL [0.0, 8423.3]), subjects with severe outcome unrelated to CDI (group 3, 158.6 pg/mL [0.0, 1795.2]), or no severe outcome (group 4, 209.5 pg/mL [0.0, 8566.3]) (P =.003). Group 1 was more likely to have detectable toxin (94.7%) than groups 2–4 (60.5%–66.1%) (P =.02). Individuals with recurrence had higher toxin A+B (2266.8 pg/mL [188.8, 29411]) than those without (154.0 pg/mL [0.0, 5864.3]) (P <.001) and higher rates of detectable toxin (85.7% versus 64.0%, P =.004). Conclusions In CDI patients, ultrasensitive stool toxin detection and concentration correlated with severe baseline disease, severe CDI-attributable outcomes, and recurrence, confirming the contribution of toxin quantity to disease presentation and clinical course. [ABSTRACT FROM AUTHOR]

Background To optimize utility of laboratory testing for Clostridiodes difficile infection (CDI), the 2017 Infectious Diseases Society of America–Society for Healthcare Epidemiology of America (IDSA-SHEA) clinical practice guidelines recommend excluding patients from stool testing for C. difficile if they have received laxatives within the preceding 48 hours. Sparse data support this recommendation. Methods Patients with new-onset diarrhea (≥3 bowel movements in any 24-hour period in the 48 hours before stool collection) and a positive stool C. difficile nucleic acid amplification test were enrolled. Laxative use within 48 hours before stool testing, severity of illness (defined by 4 distinct scoring methods), and clinical outcomes were recorded. Results 209 patients with CDI were studied, 65 of whom had received laxatives. There were no significant differences in the proportion of patients meeting severe CDI criteria by 4 severity scoring methods in patients receiving versus not receiving laxatives (66.2% vs 56.3%, respectively; P =.224) by IDSA-SHEA, the primary scoring system. Similar rates of serious outcomes attributable to CDI, including death, intensive care unit admission, and colectomy, were observed in the laxative and no laxative groups. Conclusions Our study found similar rates of severe CDI and serious CDI-attributable clinical outcomes in CDI-diagnosed patients who did or did not receive laxatives. Precluding recent laxative users from CDI testing, as proposed by the IDSA-SHEA guideline, carries a potential for harm due to delayed diagnosis and treatment. [ABSTRACT FROM AUTHOR]

The article examines biomarkers of innate and adaptive immunity in adult inpatients diagnosed with Clostridioides difficile infections (CDI), asymptomatic carriage, or diarrhea not caused by CDI. It states that CDI patients had positive nucleic acid amplification testing and clinically significant diarrhea and were treated for CDI, while those with asymptomatic carriage had positive nucleic acid amplification testing but no diarrhea. It talks about interleukin values in CDI patients.

Fine particulate matter (PM2.5) was collected in situ from peat smoke during the 2015 El Niño peat fire episode in Central Kalimantan, Indonesia. Twenty-one PM samples were collected from 18 peat fire plumes that were primarily smoldering with modified combustion efficiency (MCE) values of 0.725-0.833. PM emissions were determined and chemically characterized for elemental carbon (EC), organic carbon (OC), water-soluble OC, water-soluble ions, metals, and organic species. Fuel-based PM2.5 mass emission factors (EFs) ranged from 6.0 to 29.6 g kg-1 with an average of 17.3 ± 6.0 g kg-1. EC was detected only in 15 plumes and comprised ~1% of PM mass. Together, OC (72%), EC (1%), water-soluble ions (1%), and metal oxides (0.1%) comprised 74 ± 11% of gravimetrically measured PM mass. Assuming that the remaining mass is due to elements that form organic matter (OM; i.e., elements O, H, N) an OM-to-OC conversion factor of 1.26 was estimated by linear regression. Overall, chemical speciation revealed the following characteristics of peat-burning emissions: high OC mass fractions (72%), primarily water-insoluble OC (84 ± 11%C), low EC mass fractions (1%), vanillic to syringic acid ratios of 1.9, and relatively high n-alkane contributions to OC (6.2%C) with a carbon preference index of 1.2-1.6. Comparison to laboratory studies of peat combustion revealed similarities in the relative composition of PM but greater differences in the absolute EF values. The EFs developed herein, combined with estimates of the mass of peat burned, are used to estimate that 3.2-11 Tg of PM2.5 was emitted to atmosphere during the 2015 El Niño peatland fire event in Indonesia. Combined with gas-phase measurements of CO2, CO, CH4, and volatile organic carbon from Stockwell et al. (2016), it is determined that OC and EC accounted for 2.1 and 0.04% of total carbon emissions, respectively. These in situ EFs can be used to improve the accuracy of the representation of Indonesian peat burning in emission inventories and receptor-based models. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM2.5) was collected in situ from peat smoke during the 2015 El Niño peat fire episode in Central Kalimantan, Indonesia. Twenty-one PM samples were collected from 18 peat fire plumes that were primarily smoldering with modified combustion efficiency (MCE) values of 0.725-0.833. PM emissions were determined and chemically characterized for elemental carbon (EC), organic carbon (OC), water-soluble OC, water-soluble ions, metals, and organic species. Fuel-based PM2.5 mass emission factors (EF) ranged from 6.0-29.6 g kg-1 with an average of 17.3 ± 6.0 g kg-1. EC was detected only in 15 plumes and comprised ~ 1 % of PM mass. Together, OC (72 %), EC (1 %), water-soluble ions (1 %) and metal oxides (0.1 %) comprised 74 ± 11 % of gravimetrically-measured PM mass. Assuming that the remaining mass is due to elements that form organic matter (OM; i.e. elements O, H, N) an OM to OC conversion factor of 1.26 was estimated by linear regression. Overall, chemical speciation revealed the following characteristics of peat burning emissions: high OC mass fractions (72 %), primarily water-insoluble OC (84 ± 11 % C), low EC mass fractions (1 %), vanillic to syringic acid ratios of 1.9, and relatively high n-alkane contributions to OC (6.2 % C) with a carbon preference index of 1.2-1.6. Comparison to laboratory studies of peat combustion revealed similarities in the relative composition of PM, but greater differences in the absolute EF values. The EF developed herein, combined with estimates of the mass of peat burned, are used to estimate that 3.2-11 Tg of PM2.5 was emitted to atmosphere during the 2015 El Niño peatland fire event in Indonesia. Combined with gas-phase measurements of CO2, CO, CH4 and VOC from Stockwell et al. (2016), it is determined that OC and EC account for 2.1 % and 0.04 % of total carbon emissions, respectively. These in situ EFs can be used to improve the accuracy of the representation of Indonesian peat burning in emission inventories and receptor-based models. [ABSTRACT FROM AUTHOR]

Inflammatory Bowel Disease (IBD) is a chronic condition that affects approximately 1.6 million Americans. While current polyphenols for treating IBD can be expensive and cause unwanted side effects, there is an opportunity regarding a new drug/polymer formulation using silymarin and an electrospray procedure. Silymarin is a naturally occurring polyphenolic flavonoid antioxidant that has shown promising results as a pharmacological agent due to its antioxidant and hepatoprotective characteristics. This study aims to produce a drug-polymer complex named the SILS100-Electrofiber complex, using an electrospray system. The vertical set-up of the electrospray system was optimized at a 1:10 of silymarin and Eudragit ® S100 polymer to enhance surface area and microfiber encapsulation. The SILS100-Electrofiber complex was evaluated using drug release kinetics via UV Spectrophotometry, Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Differential Scanning Calorimetry (DSC). Drug loading, apparent solubility, and antioxidant activity were also evaluated. The study was successful in creating fiber-like encapsulation of the silymarin drug with strand diameters ranging from 5-7 μm, with results showing greater silymarin release in Simulated Intestinal Fluid (SIF) compared to Simulated Gastric Fluid (SGF). Moving forward, this study aims to provide future insight into the formulation of drug-polymer complexes for IBD treatment and targeted drug release using electrospray and microencapsulation.

Background: Despite advances in the understanding and diagnosis of Clostridioides difficile infection (CDI), clinical distinction within the colonization-infection continuum remains an unmet need., Methods: By measuring stool cytokines and antitoxin antibodies in well-characterized cohorts of CDI (diarrhea, nucleic acid amplification test [NAAT] positive), non-CDI diarrhea (NCD; diarrhea, NAAT negative), asymptomatic carriers (ASC; no diarrhea, NAAT positive) and hospital controls (CON; no diarrhea, NAAT negative), we aim to discover novel biological markers to distinguish between these cohorts. We also explore the relationship of these stool cytokines and antitoxin antibody with stool toxin concentrations and disease severity., Results: Stool interleukin (IL) 1β, stool immunoglobulin A (IgA), and immunoglobulin G (IgG) anti-toxin A had higher (P < .0001) concentrations in CDI (n = 120) vs ASC (n = 43), whereas toxins A, B, and fecal calprotectin did not. Areas under the receiver operating characteristic curve (ROC-AUCs) for IL-1β, IgA, and IgG anti-toxin A were 0.88, 0.83, and 0.83, respectively. A multipredictor model including IL-1β and IgA anti-toxin A achieved an ROC-AUC of 0.93. Stool IL-1β concentrations were higher in CDI compared to NCD (n = 75) (P < .0001) and NCD + ASC+ CON (CON, n = 75) (P < .0001), with ROC-AUCs of 0.83 and 0.86, respectively. Stool IL-1β had positive correlations with toxins A (ρA = +0.55) and B (ρB = +0.49) in CDI (P < .0001) but not in ASC (P > .05)., Conclusions: Stool concentrations of the inflammasome pathway, proinflammatory cytokine IL-1β, can accurately differentiate CDI from asymptomatic carriage and NCD, making it a promising biomarker for CDI diagnosis. Significant positive correlations exist between stool toxins and stool IL-1β in CDI but not in asymptomatic carriers., Competing Interests: Potential conflicts of interest. C. D. A. has received grant support from Merck (investigator-initiated award, paid to institution); consulting fees for advisory board from Cidara Therapeutics, Merck, and Prime Meridian Group (on behalf of AiCuris); and honoraria for presentations from the American Society of Healthcare Pharmacists. A. B. reports being an employee of bioMérieux. M. M. reports being an employee of bioMérieux and a holder of patent (Susceptibility to C. difficile infection and Fecal Immunoglobulins; bioMérieux). C. P. K. has acted as a paid consultant to Artugen, Facile Therapeutics, Ferring, First Light Biosciences, Finch, Janssen (J&J), Milky Way Life Sciences, Pfizer, Seres, Summit, RVAC Medicines, and Vedanta; has received grant support from Milky Way Life Sciences; reports participation on a data and safety monitoring board or advisory board from Finch Therapeutics (payments to self); has served as Secretary (unpaid) for the Society for the Study of Celiac Disease; and holds stock or stock options from First Light. K. W. G. has received grant support paid to the University of Houston from Acurx, Summit, Paratek Pharmaceuticals, Tetraphase Pharmaceuticals, and Seres Health, and reports consulting fees from Acurx and Summit Pharmaceuticals. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)