A worldwide systematic review and meta-analysis of bacteria related to antibiotic-associated diarrhea in hospitalized patients

An ultrasensitive genosensor for detection of toxigenic and non-toxigenic Clostridioides difficile based on a conserved sequence in surface layer protein coding gene

Clostridioides difficile (C. difficile) is the most common agent of antibiotic-associated diarrhea, leading to intestinal infection through the secretion of two major toxins. Not all strains of this bacterium are toxigenic, but some of them cause infection via their accessory virulence factors, such as surface layer protein (SlpA). SlpA is conserved in both toxigenic and non-toxigenic strains of C. difficile. In the present work, an amplification-free electrochemical genosensor was designed for the detection of the slpA gene. A glassy carbon electrode coated with gold nanoparticle-reduced graphene oxide nanocomposite was used as the working electrode, and its surface was modified using a simple thiolated linear oligonucleotide as the bioreceptor. Moreover, the hexaferrocenium tri[hexa(isothiocyanato) iron(III)] trihydroxonium (HxFc) complex was used as an intercalator, and its redox signal was recorded using differential pulse voltammetry. Scan rate studies indicated a quasi-reversible adsorption-controlled process for the HxFc complex. This genosensor showed high sensitivity with a limit of detection of 0.2 fM, a linear response range of 0.46-1900 fM, and a satisfactory specificity toward the synthetic slpA target gene. Also, the genosensor indicated responses in the mentioned linear range toward the genome extracted from either toxigenic or non-toxigenic strains of C. difficile.

Interpretable machine learning models for predicting the incidence of antibiotic- associated diarrhea in elderly ICU patients

BACKGROUND

Antibiotic-associated diarrhea (AAD) can prolong hospitalization, increase medical costs, and even lead to higher mortality rates. Therefore, it is essential to predict the incidence of AAD in elderly intensive care unit(ICU) patients. The objective of this study was to create a prediction model that is both interpretable and generalizable for predicting the incidence of AAD in elderly ICU patients.

METHODS

We retrospectively analyzed data from the First Medical Center of the People's Liberation Army General Hospital (PLAGH) in China. We utilized the machine learning model Extreme Gradient Boosting (XGBoost) and Shapley's additive interpretation method to predict the incidence of AAD in elderly ICU patients in an interpretable manner.

RESULTS

A total of 848 adult ICU patients were eligible for this study. The XGBoost model predicted the incidence of AAD with an area under the receiver operating characteristic curve (ROC) of 0.917, sensitivity of 0.889, specificity of 0.806, accuracy of 0.870, and an F1 score of 0.780. The XGBoost model outperformed the other models, including logistic regression, support vector machine (AUC = 0.809), K-nearest neighbor algorithm (AUC = 0.872), and plain Bayes (AUC = 0.774).

CONCLUSIONS

While the XGBoost model may not excel in absolute performance, it demonstrates superior predictive capabilities compared to other models in forecasting the incidence of AAD in elderly ICU patients categorized based on their characteristics.

C. difficile biomarkers, pathogenicity and detection

BACKGROUND

Clostridioides difficile infection (CDI) is the main etiologic agent of antibiotic-associated diarrhea. CDI contributes to gut inflammation and can lead to disruption of the intestinal epithelial barrier. Recently, the rate of CDI cases has been increased. Thus, early diagnosis of C. difficile is critical for controlling the infection and guiding efficacious therapy.

APPROACH

A search strategy was set up using the terms C. difficile biomarkers and diagnosis. The found references were classified into two general categories; conventional and advanced methods.

RESULTS

The pathogenicity and biomarkers of C. difficile, and the collection manners for CDI-suspected specimens were briefly explained. Then, the conventional CDI diagnostic methods were subtly compared in terms of duration, level of difficulty, sensitivity, advantages, and disadvantages. Thereafter, an extensive review of the various newly proposed techniques available for CDI detection was conducted including nucleic acid isothermal amplification-based methods, biosensors, and gene/single-molecule microarrays. Also, the detection mechanisms, pros and cons of these methods were highlighted and compared with each other. In addition, approximately complete information on FDA-approved platforms for CDI diagnosis was collected.

CONCLUSION

To overcome the deficiencies of conventional methods, the potential of advanced methods for C. difficile diagnosis, their direction, perspective, and challenges ahead were discussed.

Anti-diarrheal effect of piperine possibly through the interaction with inflammation inducing enzymes: In vivo and in silico studies

Piperine is a natural alkaloid that possesses a variety of therapeutic properties, including anti-inflammatory, antioxidant, antibacterial, and anticarcinogenic activities. The present study aims to assess the medicinal benefits of piperine as an anti-diarrheal agent in a chick model by utilizing in vivo and in silico techniques. For this, castor oil was administered orally to 2-day-old chicks to cause diarrhea. Bismuth subsalicylate (10 mg/kg), loperamide (3 mg/kg), and nifedipine (2.5 mg/kg) were used as positive controls, while the vehicle was utilized as a negative control. Two different doses (25 and 50 mg/kg b.w.) of the test sample (piperine) were administered orally, and the highest dose was tested with standards to investigate the synergistic activity of the test sample. In our findings, piperine prolonged the latent period while reducing the number of diarrheal feces in the experimental chicks during the monitoring period (4 h). At higher doses, piperine appears to reduce diarrheal secretion while increasing latency in chicks. Throughout the combined pharmacotherapy, piperine outperformed bismuth subsalicylate and nifedipine in terms of anti-diarrheal effects with loperamide. In molecular docking, piperine exhibited higher binding affinities towards different inflammatory enzymes such as cyclooxygenase 1 (-7.9 kcal/mol), cyclooxygenase 2 (-8.4 kcal/mol), nitric oxide synthases (-8.9 kcal/mol), and L-type calcium channel (-8.8 kcal/mol), indicating better interaction of PP with these proteins. In conclusion, piperine showed a potent anti-diarrheal effect in castor oil-induced diarrheal chicks by suppressing the inflammation and calcium ion influx induced by castor oil.

Relationship among Chinese herb polysaccharide (CHP), gut microbiota, and chronic diarrhea and impact of CHP on chronic diarrhea

Chronic diarrhea, including diarrhea-predominant irritable bowel syndrome (IBS-D), osmotic diarrhea, bile acid diarrhea, and antibiotic-associated diarrhea, is a common problem which is highly associated with disorders of the gut microbiota composition such as small intestinal bacterial overgrowth (SIBO) and so on. A growing number of studies have supported the view that Chinese herbal formula alleviates the symptoms of diarrhea by modulating the fecal microbiota. Chinese herbal polysaccharides (CHPs) are natural polymers composed of monosaccharides that are widely found in Chinese herbs and function as important active ingredients. Commensal gut microbiota has an extensive capacity to utilize CHPs and play a vital role in degrading polysaccharides into short-chain fatty acids (SCFAs). Many CHPs, as prebiotics, have an antidiarrheal role to promote the growth of beneficial bacteria and inhibit the colonization of pathogenic bacteria. This review systematically summarizes the relationship among gut microbiota, chronic diarrhea, and CHPs as well as recent progress on the impacts of CHPs on the gut microbiota and recent advances on the possible role of CHPs in chronic diarrhea.

Molecular characteristics and phylogenetic analysis of Clostridium perfringens from different regions in China, from 2013 to 2021

Clostridium perfringens (C. perfringens) is a significant foodborne pathogen and a common cause of intestinal diseases in both animals and humans. Our study investigated MLST, phenotypic antimicrobial resistance profiles, and resistance genes among isolates from human, animal and food. 186 C. perfringens isolates were obtained from nine provinces in China between 2013 and 2021. Additionally, some specific ST complexes were analyzed by cgMLST and cgSNP to investigate genetic relatedness. MLST indicated the most prevalent STs of C. perfringens of human and animal origin were as follows: ST221 (5/147), ST62 (4/147), ST408 (4/147), and ST493 (4/147) were predominant in humans, while ST479 (5/25) was the major type in animals. Within the same ST complex, genetically unrelated relationships or potential clustering/transmission events were further recognized by cgMLST and cgSNP, illustrating that these two methods are valuable in defining outbreaks and transmission events. All tested isolates were susceptible to vancomycin and meropenem. The rates of resistance to metronidazole, penicillin, cefoxitin, moxifloxacin, and chloramphenicol were low (metronidazole: 1.08%; penicillin: 9.68%; cefoxitin: 0.54%; moxifloxacin: 6.45%; and chloramphenicol: 3.76%). Interestingly, 49.66% of human origin were clindamycin-resistant, and 18.2% were penicillin-insensitive. Importantly, the portion of MDR isolates was significantly lower than in previous reports. The study provides an overview of the epidemiological characteristics of C. perfringens with different origins and hosts in China. C. perfringens demonstrated remarkable genetic diversity and distinct molecular features compared to antibiotic-resistance profiles from other studies.

Genomic Insights into Virulence Factors and Multi-Drug Resistance in Clostridium perfringens IRMC2505A

Clostridium perfringens is a spore-forming, Gram-positive anaerobic pathogen that causes several disorders in humans and animals. A multidrug-resistant Clostridium strain was isolated from the fecal sample of a patient who was clinically suspected of gastrointestinal infection and had a recent history of antibiotic exposure and diarrhea. The strain was identified by 16s rRNA sequencing as Clostridium perfringens. The strain's pathogenesis was analyzed through its complete genome, specifically antimicrobial resistance-related genes. The Clostridium perfringens IRMC2505A genome contains 19 (Alr, Ddl, dxr, EF-G, EF-Tu, folA, Dfr, folP, gyrA, gyrB, Iso-tRNA, kasA, MurA, rho, rpoB, rpoC, S10p, and S12p) antibiotic-susceptible genetic species according to the k-mer-based detection of antimicrobial resistance genes. Genome mapping using CARD and VFDB databases revealed significant (p-value = 1 × 10^-26) genes with aligned reads against antibiotic-resistant genes or virulence factors, including phospholipase C, perfringolysin O, collagenase, hyaluronidase, alpha-clostripain, exo-alpha-sialidase, and sialidase activity. In conclusion, this is the first report on C. perfringens from Saudi Arabia that conducted whole genome sequencing of IRMC2505A and confirmed the strain as an MDR bacterium with several virulence factors. Developing control strategies requires a detailed understanding of the epidemiology of C. perfringens, its virulence factors, and regional antimicrobial resistance patterns.

Shengjiang Xiexin Decoction ameliorates antibiotic-associated diarrhea by altering the gut microbiota and intestinal metabolic homeostasis

BACKGROUND

Antibiotic-associated diarrhea (AAD) has had a significant increase in the last years, with limited available effective therapies. Shengjiang Xiexin Decoction (SXD), a classic traditional Chinese medicine formula for treating diarrhea, is a promising alternative for reducing the incidence of AAD.

PURPOSE

This study aimed to explore the therapeutic effect of SXD on AAD and to investigate its potential therapeutic mechanism by integrated analysis of the gut microbiome and intestinal metabolic profile.

METHODS

16S rRNA sequencing analysis of the gut microbiota and untargeted-metabolomics analysis of feces were performed. The mechanism was further explored by fecal microbiota transplantation (FMT).

RESULTS

SXD could effectively ameliorate AAD symptoms and restore intestinal barrier function. In addition, SXD could significantly improve the diversity of the gut microbiota and accelerate the recovery of the gut microbiota. At the genus level, SXD significantly increased the relative abundance of Bacteroides spp (p < 0.01) and decreased the relative abundance of Escherichia_Shigela spp (p < 0.001). Untargeted metabolomics showed that SXD significantly improved gut microbiota and host metabolic function, particularly bile acid metabolism and amino acid metabolism.

CONCLUSION

This study demonstrated that SXD could extensively modulate the gut microbiota and intestinal metabolic homeostasis to treat AAD.

Prevalence and molecular characterization of Clostridioides difficile infection in China over the past 5 years: a systematic review and meta-analysis

OBJECTIVES

The aim of this study was to provide an overview of the prevalence and molecular characteristics of Clostridioides difficile infection (CDI) in China in the past 5 years.

METHODS

A systematic literature review was conducted according to the preferred reporting items for systematic reviews and meta-analyses guidelines. Nine databases were searched for relevant studies published between January 2017 and February 2022. The Joanna Briggs Institute critical appraisal tool was used to assess the quality of included studies, and R software version 4.1.3 was used for data analysis. Funnel plots and Egger regression tests were also performed to assess publication bias.

RESULTS

A total of 50 studies were included in the analysis. The pooled prevalence of CDI in China was 11.4% (2696/26,852). The main circulating C. difficile strains in southern China were ST54, ST3, and ST37, consistent with the overall situation in China. However, the most prevalent genotype in northern China was ST2, which was previously underappreciated.

CONCLUSION

Based on our findings, increased awareness and management of CDI is necessary to reduce the prevalence of CDI in China.

The diarrheal mechanism of mice with a high-fat diet in a fatigued state is associated with intestinal mucosa microbiota

Growing evidence has demonstrated that fatigue and a high-fat diet trigger diarrhea, and intestinal microbiota disorder interact with diarrhea. However, the association of intestinal mucosal microbiota with fatigue and high-fat diet trigger diarrhea remains unclear. The specific pathogen-free Kunming male mice were randomly divided into the normal group (MCN), standing group (MSD), lard group (MLD), and standing united lard group (MSLD). Mice in the MSD and MSLD groups stood on the multiple-platform apparatus for four h/d for fourteen consecutive days. From the eighth day, mice in the MLD and MSLD groups were intragastric lard, 0.4 mL/each, twice a day for seven days. Subsequently, we analyzed the characteristics and interaction relationship of intestinal mucosal microbiota, interleukin-6 (IL-6), interleukin-17 (IL-17), malondialdehyde (MDA), superoxide dismutase (SOD), and secretory immunoglobulin A (sIgA). Results showed that mice in the MSLD group had an increased number of bowel movements. Compared with the MCN group, the contents of IL-17, and IL-6 were higher (p > 0.05), and the content of sIgA was lower in the MSLD group (p > 0.05). MDA and SOD increased in MLD and MSLD groups. Thermoactinomyces and Staphyloccus were the characteristic bacteria of the MSLD group. And Staphyloccus were positively correlated with IL-6, IL-17, and SOD. In conclusion, the interactions between Thermoactinomyces, Staphyloccus and intestinal inflammation, and immunity might be involved in fatigue and high-fat diet-induced diarrhea.

Non-clostridium difficile induced pseudomembranous colitis

Pseudomembranous colitis is severe inflammation of the inner lining of the colon due to anoxia, ischemia, endothelial damage, and toxin production. The majority of cases of pseudomembranous colitis are due to Clostridium difficile. However, other causative pathogens and agents have been responsible for causing a similar pattern of injury to the bowel with the endoscopic appearance of yellow-white plaques and membranes on the mucosal surface of the colon. Common presenting symptoms and signs include crampy abdominal pain, nausea, watery diarrhea that can progress to bloody diarrhea, fever, leukocytosis, and dehydration. Negative testing for Clostridium difficile or failure to improve on treatment should prompt evaluation for other causes of pseudomembranous colitis. Bacterial infections other than Clostridium difficile, Viruses such as cytomegalovirus, parasitic infections, medications, drugs, chemicals, inflammatory diseases, and ischemia are other differential diagnoses to look out for in pseudomembranous colitis. Complications of pseudomembranous colitis include toxic megacolon, hypotension, colonic perforation with peritonitis, and septic shock with organ failure. Early diagnosis and treatment to prevent progression are important. The central perspective of this paper is to provide a concise review of the various etiologies for pseudomembranous colitis and management per prior literature.

Clostridium difficile colitis and peritoneal dialysis associated peritonitis: ‘Difficile’ treatment considerations

Peritoneal dialysis (PD) associated peritonitis is the leading cause of PD discontinuation and haemodialysis transfer. Current guidelines strongly recommend prompt initiation of empiric broad-spectrum intraperitoneal antibiotics, with suspected peritonitis. Clostridium difficile colitis is one of the most common healthcare-associated infections, with increased morbidity and mortality among end-stage kidney disease patients. Clinical presentation is mainly characterised by diarrhoea of varying severity, which may eventually evolve into toxic megacolon and paralytic ileus. However, PD patients with Clostridium difficile infection (CDI) may also have colitis-triggered peritonitis, presenting challenging scenario for antibiotic treatment strategy, since broad-spectrum antibiotics against peritonitis may worsen CDI-related colitis, while inappropriate or discontinuation of antibiotic therapy may worsen peritonitis. Currently, guidelines on peritonitis management do not include such challenging clinical situations, although increasingly common. We herein describe a case of a patient, with culture-negative PD associated peritonitis and CDI, presenting with diarrhoea, abdominal pain and cloudy effluent.

Prevalence of Clostridioides difficile contamination in the healthcare environment and instruments: A systematic review and meta-analysis

Introduction

Worldwide, Clostridioides difficile infection is becoming one of the most common healthcare-associated infections. Management and control of this infection in healthcare facilities are associated with screening for environmental and instrumental C. difficile contamination. This systematic review and meta-analysis aimed to assess the overall prevalence of C. difficile in hospital settings, medical devices, and instruments.

Methods

Four main databases, PubMed, Web of Science, Google Scholar, and Scopus, were searched using the keywords Clostridioides difficile, Clostridium difficile, C. difficile, clostridia, Clostridium spp., hospital environments, antibiotic associate colitis, intensive care unit, and ward in combination as a search strategy. The PRISMA checklist was used for selecting eligible studies.

Results

A total of 11 eligible articles published between 2012 and 2021 were included. The overall pooled prevalence of C. difficile in hospital environments was 14.9%. The highest and lowest prevalence were reported for India (51.1%) and the USA (1.6%), respectively. The highest prevalence was reported for beds (46.3%). A significant heterogeneity was seen between C. difficile prevalence in hospital environments in different samples. The highest and lowest prevalence was reported for floor corners (63.2%) and privacy curtains (1.4%), respectively.

Conclusions

In conclusion, hospitals' medical devices and environmental surfaces are considered a crucial source of Clostridioides difficile infection. In this regard, we strongly recommend revising and improving the cleaning and disinfection methods in hospitals and quality control of cleaning adequacy.

Neglected Case of Human Balantidiasis: Presumed as Antibiotic-Associated Diarrhoea

Background

Balantidiasis, due to its rare human incidence and nonspecific clinical presentations often neglected from the diagnosis considerations; however, a potent pathogen. Herein, we report a case of neglected balantidiasis presumed as antibiotic-associated diarrhoea. Case Presentation. A 27-year-old policeman presented in Sindhuli Hospital, with a chief complaint of epigastric pain, nausea, decreased appetite for several days, and loose stools (3-4 episodes per day). Previously, he was under antibiotic therapy (amoxycillin) for tonsillitis. The health post clinician made a presumptive diagnosis as the side effects of the antibiotics; however, the symptoms were not resolved. Complete blood cell count (CBC) was normal; renal function test (RFT) and liver function (LFT) were within the normal ranges. Ultrasonography of the abdomen and ECG (electrocardiogram) showed normal findings. However, on routine stool actively motile trophozoites of Balantidium coli (B. coli) were seen. He was treated successfully with metronidazole 750 mg tabs orally three times daily for 5 days.

Conclusion

Protozoal infections, like balantidiasis, might be excluded from the diagnostic consideration in antibiotic-associated diarrhoea cases. Therefore, meticulous review of nonspecific clinical presentation and validation of an etiology with support of diagnostic tests are mandatory.

Use of antibiotics after lower third molar surgery - useful or harmful procedure? A randomized, double-blind, placebo-controlled trial

Introduction/Objective. The aim of the present study was to investigate the effects of moxifloxacin and cefixime in preventing postoperative infection following mandibular third molar surgery. Methods. Double-blind study was completed by 157 patients undergoing surgical removal of mandibular third molars. Patients were randomly assigned to three groups: moxifloxacin (M), cefixime (C) and placebo (P). Patients in each group were classified into two subgroups: subgroup (a) without previous history of pericoronitis and subgroup (b) with previous history of pericoronitis. All patients were evaluated at the postoperative follow-ups on the first, second and seventh postoperative day. Results. Postoperative infections were registered only in patients with history of pericoronitis. Antibiotic prophylaxis with cefixime, and moxifloxacin, reduced the occurrence of postoperative infection. Overall incidence of postoperative infections was 6.4%. All postoperative infections were registered in placebo-group, where the incidence of postoperative infection was 19.2%. Microbiological tests verified the clinically obtained results. Isolated microflora was resistant to penicillin-derived antibiotics in 50% of cases. Conclusion. Prophylactic use of antibiotics after third molar surgery should be weighted against potential risks and benefits and could be considered in cases with previous history of pericoronitis, when complicated surgical extraction is performed.