Prevalence of human norovirus and Clostridium difficile coinfections in adult hospitalized patients

Epidemiology and Economic Burden of Acute Infectious Gastroenteritis Among Adults Treated in Outpatient Settings in US Health Systems

INTRODUCTION

Acute infectious gastroenteritis (AGE) is a common reason for outpatient visits and hospitalizations in the United States. This study aimed to understand the demographic and clinical characteristics, common pathogens detected, health care resource utilization (HRU), and cost among adult outpatients with AGE visiting US health systems.

METHODS

A retrospective cohort study was conducted using one of the largest hospital discharge databases (PINC AI Healthcare Database) in the United States. Adult patients (aged ≥18 years) with a principal diagnosis of AGE during an outpatient visit between January 1, 2016, and June 30, 2021, were included. Pathogen detection analysis was performed in those with microbiology data available.

RESULTS

Among 248,896 patients, the mean age was 44.3 years (range 18-89+ years), 62.9% were female, and 68.5% were White. More than half (62.0%) of the patients did not have any preexisting comorbidity, and only 18.3% underwent stool workup at the hospital. Most patients (84.7%) were seen in the emergency department, and most (96.4%) were discharged home. Within 30 days of discharge, 1.0% were hospitalized, and 2.8% had another outpatient visit due to AGE. The mean cost of the index visit plus 30-day AGE-related follow-up was $1,338 per patient, amounting to $333,060,182 for the total study population. Among patients with microbiology data available (n = 12,469), common pathogens detected were Clostridioides difficile (32.2%), norovirus (6.3%), and Campylobacter spp. (4.0%).

DISCUSSION

AGE is a common and costly disease affecting adults of all ages and more females than males, including individuals with or without baseline conditions in a hospital-based outpatient setting. C. difficile was the most common pathogen detected.

Bacteria Associated with Healthcare-Associated Infections on Environmental Samples Obtained from Two Fire Departments

(1) Background: Firefighters spend about 64% of their time responding to medical emergencies and providing medical care without a patient history, which can render them vulnerable to healthcare-associated infections (HAI). Infection prevention, control, and surveillance systems have been instituted at hospitals. However, the prevalence of firefighters’ exposure to HAI is unknown. The objective of this study was to document evidence of HAI on surfaces in fire stations and engines to inform disinfection procedures and identify which pathogens might contribute to occupational exposures. (2) Methods: High-touch or high-use surfaces of two fire departments were sampled during five separate occasions. One fire station from one fire department was sampled over a 4-week period, whereas four fire stations were sampled from a different fire department only once. Sampled surfaces included: entryway floor, washing machine, medical bag, back seat of engine, keyboard of reporting computer, engine console, and uniform pants. (3) Results: Multiple statistical models determined that bacterial contamination was similar between the two fire departments and their stations. Keyboards were the most contaminated surface for all fire stations and departments, E. coli was the most common bacteria detected, and C. difficile was the least detected bacteria. Adjustments for rates of contamination found that contamination rates varied between fire stations. (4) Conclusions: Comprehensive environmental sampling and clinical studies are needed to better understand occupational exposures of firefighters to HAI.

Norovirus in Cancer Patients: A Review

Norovirus (NoV) is the leading cause of viral-related diarrhea in cancer patients, in whom it can be chronic, contributing to decreased quality of life, interruption of cancer care, malnutrition, and altered mucosal barrier function. Immunosuppressed cancer patients shed NoV for longer periods of time than immunocompetent hosts, favoring quasispecies development and emergence of novel NoV variants. While nucleic acid amplification tests (NAATs) for NoV diagnosis have revolutionized our understanding of NoV burden of disease, not all NAATs provide information on viral load or infecting genotype. There is currently no effective antiviral or vaccine for chronic NoV infections. Screening for inhibitors of NoV replication in intestinal organoid culture models and creation of NoV-specific adoptive T cells are promising new strategies to develop treatments for chronic NoV in immunosuppressed patients. Herein we summarize data on the epidemiology, clinical manifestations, diagnostic challenges, and treatment of NoV infection in patients with cancer.

Clostridioides difficile Infection: The Challenge, Tests, and Guidelines

Clostridioides difficile is a dangerous human pathogen because it can grow to high numbers in the intestine, cause colitis with its potent toxins, and persist as spores. C. difficile infection (CDI) is the primary hospital-acquired infection in North America and Europe, and it now is a global disease. Even with newer laboratory tests, there still is confusion on accurately diagnosing this disease. Three guidelines from three different healthcare-affiliated societies have recently been published. Consensus consolidated recommendations from these guidelines should be recognized by healthcare professionals, who need to understand why this disease continues to be difficult to diagnose and need a clear understanding of the advantages and limitations of current tests. Hopefully, these combined efforts will lead to an improvement in the recognition of this pathogen and a reduction in the suffering and economic loss caused by CDI.

Evaluation of viral co-infections among patients with community-associated Clostridioides difficile infection

We assessed viral co-infections in 155 patients with community-associated Clostridioides difficile infection in five U.S. sites during December 2012–February 2013. Eighteen patients (12%) tested positive for norovirus (n = 10), adenovirus (n = 4), rotavirus (n = 3), or sapovirus (n = 1). Co-infected patients were more likely than non-co-infected patients to have nausea or vomiting (56% vs 31%; p = 0.04), suggesting that viral co-pathogens contributed to symptoms in some patients. There were no significant differences in prior healthcare or medication exposures or in CDI complications.

Molecular characteristics of Clostridium difficile in children with acute gastroenteritis from Zhejiang

Background

Clostridium difficile infection (CDI) has an increasing pediatric prevalence worldwide. However, molecular characteristics of C. difficile in Chinese children with acute gastroenteritis have not been reported.

Methods

A five-year cross-sectional study was conducted in a tertiary children’s hospital in Zhejiang. Consecutive stool specimens from outpatient children with acute gastroenteritis were cultured for C. difficile, and isolates then were analyzed for toxin genes, multi-locus sequence type and antimicrobial resistance. Diarrhea-related viruses were detected, and demographic data were collected.

Results

A total of 115 CDI cases (14.3%), and 69 co-infected cases with both viruses and toxigenic C. difficile, were found in the 804 stool samples. The 186 C. difficile isolates included 6 of toxin A-positive/toxin B-positive/binary toxin-positive (A⁺B⁺CDT⁺), 139 of A⁺B⁺CDT⁻, 3 of A⁻B⁺CDT⁺, 36 of A⁻B⁺CDT⁻ and 2 of A⁻B⁻CDT⁻. Sequence types 26 (17.7%), 35 (11.3%), 39 (12.4%), 54 (16.7%), and 152 (11.3%) were major genotypes with significant differences among different antimicrobial resistances (Fisher's exact test, P < 0.001). The A⁻B⁺ isolates had significantly higher resistance, compared to erythromycin, rifampin, moxifloxacin, and gatifloxacin, than that of the A⁺B⁺ (χ² = 7.78 to 29.26, P < 0.01). The positive CDI rate in infants (16.2%) was significantly higher than that of children over 1 year old (10.8%) (χ² = 4.39, P = 0.036).

Conclusions

CDI has been revealed as a major cause of acute gastroenteritis in children with various genotypes. The role of toxigenic C. difficile and risk factors of CDI should be emphatically considered in subsequent diarrhea surveillance in children from China.

Characterization of Circulating Clostridium difficile Strains, Host Response and Intestinal Microbiome in Hospitalized Children With Diarrhea

BACKGROUND

Clostridium difficile is capable of causing severe enterocolitis in adults. The significance of toxin-producing C. difficile in children with diarrhea is unclear and practice differs on whether to institute treatment. We aimed to characterize the microbiome in relation to the presence of C. difficile and co-infection with other pathogens and to describe host response to infection.

METHODS

Participants were children with acute diarrhea, 0-16 years of age, from whom stool samples had been submitted to the hospital laboratory for routine microbiology/virology. Convenience sampling was used for 50 prospective and 150 retrospective samples. No participants were treated for C. difficile. Rates of culture positivity for C. difficile, presence of toxin and PCR-ribotype were compared between age groups. Presence of other potential pathogens, comorbidities and complications were recorded. Microbiotal diversity was measured by 16S profiling.

RESULTS

Nineteen of 77 (25%) children <2 years of age and 13 of 119 (11%) children >2 years of age were C. difficile positive, of whom 10 (53%) and 9 (69%), respectively, carried toxigenic strains. Increased Shannon diversity was seen in children carrying C. difficile, with altered milieu. Presence of C. difficile was not associated with adverse clinical outcomes. In stools containing both Norovirus and C. difficile, there was increased relative abundance of verrucomicrobia.

CONCLUSIONS

Children with diarrhea regularly carried toxigenic and non-toxigenic strains of C. difficile, demonstrating enhanced microbiotal diversity, and change in milieu, without apparent morbidity. This unexpected finding is contrary to that seen in adults with C. difficile disease.

Effects of co-infection on the clinical outcomes of Clostridium difficile infection

Background

Clostridium difficile (C. difficile) is a spore-forming, Gram-positive rod that is known to be associated with antibiotic use. It is one of the leading causes of nosocomial diarrhea in the industrialized world and therefore warrants further study of its nature. It isn't clear if co-infection by other organisms can affect the outcome of C. difficile infection (CDI).

Methods

A single center retrospective study was done and it used inclusion criteria of 18 years of age and being tested positive for CDI on FilmArray® multiplex gastro-intestinal (GI) panel. Exclusion criteria were a GI panel performed on an outpatient basis, recurrent CDI, and the presence of end-stage renal disease, cirrhosis, or a non-GI infection. The stool sample for all patients were collected within 48 h of presentation to the hospital. There were 235 of 2576 GI panels selected for a retrospective chart review based on the above criteria. Among these 235 patients, 38 had a co-infection (CDI+ another GI infection = group A or cases) and the rest had only CDI (group B or controls). Group A was compared with group B for CDI severity, its response to treatment, recurrence, and length of the hospital stay, using 0.05 as the alpha criterion.

Results

Most patients with CDI were female and above the age of 60 years. Co infection did not increase the severity of CDI based both on the American College of Gastroenterology criteria (p 0.16) as well as Infectious Disease Society of America criteria (p 0.77). Co infection group also didn't have significantly different CDI related treatment failure rate (p 0.23), or CDI recurrence rate (p 0.49). Co-infection was also not associated with lengthier hospital stay (p 0.41).

Conclusion

Our study suggests that co-infection doesn't affect the severity of CDI or can cause treatment failures. Additionally, there was no significant increase in hospital stay, or increase in CDI recurrence associated with co-infection. Therefore, if CDI is the leading clinical diagnosis and a patient is tested positive for co-infection in addition to CDI on FilmArray® multiplex GI panel, this co-infection shouldn't change the management for CDI. Limitations of this study (including retrospective nature of the study, small sample size, single site study, not including all microbiome and non-inclusion of race) should also be taken into account, while considering the applicability of the results of this study.

Recurrent community-acquired Clostridium(Clostridioides)difficile infection in Serbianchildren

Information on recurrent Clostridium difficile infections (rCDI) in children is rare and limited, especially community acquired (CA-CDI).This study was designed to identify risk factors for rCA-CDI in Serbian pediatric population. The study group included 71 children (aged from 1 to 14 years) with a first episode of CDI. Data were collected from 56 (78.87%) children with only one episode of CA-CDI and from 15 (21.13%) children with rCA-CDI were mutually compared. The following parameters were found to be statistically significantly more frequent in the children with rCA-CDI group (p < 0.05); leukemia as underlying disease, treatment with immunosuppressive and-or cytostatic drugs, and treatment with antibiotics. Similarly, previously visits to outpatient facilities, daycare hospitals and hospitals were also associated with rCDI. Analysis of clinical symptoms and laboratory parameters, revealed a statistically significant association of the severity of the first episode of CDI (determined by an increase in body temperature, higher maximum WBC and higher CRP) with development of a rCDI. Ribotype (RT) 027 was more common in children with rCA-CDI (66.7%, p = 0.006). During the seven-year research period, we found a rate of rCA-CDI rate in children of 21.13%. Our study identified several parameters statistically significantly more frequently in children with rCA-CDI. The obtained results will serve as a basis for future larger studies, but new prospective, studies are necessary to build a prediction model of rCDI in children that can be used to guide the treatment to prevent rCDI.

Microbiological Characterization and Clinical Outcomes After Extended-Pulsed Fidaxomicin Treatment for Clostridioides difficile Infection in the EXTEND Study

Background

Clostridioides (Clostridium) difficile infection (CDI) is diagnosed using clinical signs and symptoms plus positive laboratory tests. Recurrence of CDI after treatment is common, and coinfection with other enteric pathogens may influence clinical outcomes.

Methods

We aimed to assess rates of C difficile positivity, by enzyme-linked immunosorbent assay (ELISA) toxin A/B and BioFire FilmArray, and the effect of enteric coinfection on clinical outcomes, using samples from the EXTEND study of extended-pulsed fidaxomicin (EPFX) versus standard vancomycin.

Results

All 356 randomized and treated patients tested positive for C difficile toxin A/B by local tests; a majority (225 of 356, 63.2%) also tested positive by both ELISA and BioFire. Most stool samples taken at screening tested positive for C difficile only using BioFire (EPFX: 112 of 165, 69.7%; vancomycin: 118 of 162, 72.8%). Of the 5 patients who failed treatment and had stool samples available, all (1) had tested negative for C difficile by BioFire at screening and (2) were negative by ELISA at time of treatment failure. When analyzed by BioFire results at screening, rates of sustained clinical cure at 30 days after end of treatment were numerically higher with EPFX than with vancomycin for almost all patients, except for those who tested negative for C difficile but positive for another pathogen. However, these outcome differences by presence of coinfection did not reach statistical significance. Whole-genome sequencing analysis determined that 20 of 26 paired samples from patients with recurrence were reinfections with the same C difficile strain.

Conclusions

Testing for presence of copathogens in clinical trials of antibiotics could help to explain clinical failures.

Gastrointestinal Organoids: Understanding the Molecular Basis of the Host-Microbe Interface

In recent years, increasing attention has been devoted to the concept that microorganisms play an integral role in human physiology and pathophysiology. Despite this, the molecular basis of host-pathogen and host-symbiont interactions in the human intestine remains poorly understood owing to the limited availability of human tissue, and the biological complexity of host-microbe interactions. Over the past decade, technological advances have enabled long-term culture of organotypic intestinal tissue derived from human subjects and from human pluripotent stem cells, and these in vitro culture systems already have shown the potential to inform our understanding significantly of host-microbe interactions. Gastrointestinal organoids represent a substantial advance in structural and functional complexity over traditional in vitro cell culture models of the human gastrointestinal epithelium while retaining much of the genetic and molecular tractability that makes in vitro experimentation so appealing. The opportunity to model epithelial barrier dynamics, cellular differentiation, and proliferation more accurately in specific intestinal segments and in tissue containing a proportional representation of the diverse epithelial subtypes found in the native gut greatly enhances the translational potential of organotypic gastrointestinal culture systems. By using these tools, researchers have uncovered novel aspects of host-pathogen and host-symbiont interactions with the intestinal epithelium. Application of these tools promises to reveal new insights into the pathogenesis of infectious disease, inflammation, cancer, and the role of microorganisms in intestinal development. This review summarizes research on the use of gastrointestinal organoids as a model of the host-microbe interface.