Search Results (33)

Background/Objectives: Clostridioides difficile is a “One Health” pathogen and a cause of antibiotics-associated diarrhea and pseudomembranous colitis. Mobile genetic elements (MGEs) have been documented in the genomes of clinical C. difficile strains; however, the presence of MGEs in environmental strains remains poorly characterized. Thus, the present study was conducted with the objective of identifying the prevalence of MGEs, including mobilizable transposons (MTns), conjugative transposons (CTns), plasmids, and insertion sequences, in whole genome sequences (WGSs) of environmental C. difficile isolates. Methods: The analysis of MGEs was conducted using 166 WGSs obtained from C. difficile strains isolated from various environmental sources contaminated with feces. The MGEs were identified using bioinformatic tools. Results: A total of 48.2% (80/166) of the studied genomes were identified to harbor nine transposons, including Tn916, Tn6194-like, Tn5397, Tn6215, Tn4001, Tn6073, Tn6110, Tn6107, or Tn5801-like. The majority of MTns and CTns could be found within C. difficile sequence types ST11, ST3, and ST35. The results demonstrated close genetic relatedness among the studied genomes, the array of antimicrobial resistance (AMR) genes, such as tetM, ermB, and aac(6′)-aph(2″), and the presence of CTns. Furthermore, the analysis revealed that 24.7% (41/166) of the genome sequences of isolates were associated with various predominant plasmid groups, including pCD6, pCD-ECE4-6, pCD-WTSI1-4, pCDBI1, and pCd1_3, which belonged to 16 different sequence types. Furthermore, several plasmids were identified as harboring the prophage phiCDHM19. Conclusions: The results of the current study suggest that the identified plasmids are abundant and may encode functions that are relevant to C. difficile physiology. The genomes of C. difficile strains examined contain closely related CTns, suggesting that horizontal transfer of AMR is important in this species or other bacterial species. Further research is required to ascertain the effect of these genetic elements and their transferability on the biology of C. difficile. Full article

Introduction: Clostridioides difficile (C. difficile) is primarily associated with colonic disease, including pseudomembranous colitis. However, in rare instances, it may cause extraintestinal infectious and non-infectious manifestations, particularly in immunocompromised patients or those with significant underlying conditions. Search Methods: A literature review was performed using PubMed, Embase, and Researchgate databases up to 15 February 2025. The following search strings were used: “extraintestinal manifestations”, “extracolonic manifestations”, “extraintestinal infections”, “extracolonic infections”, “Clostridium difficile”, and “Clostridioides difficile”. Results: Extraintestinal manifestations of C. difficile appear to represent fewer than 1% of all reported infections. The most frequently reported infectious complications include bacteremia and abdominopelvic infections and abscesses, often involving polymicrobial cultures, with the isolation of C. difficile alongside microorganisms typically found in the normal intestinal microbiota. Rare non-infectious cases, such as reactive arthritis, have also been described. The underlying pathogenetic mechanism is believed to involve disruption of the intestinal barrier and translocation of bacteria or toxins to sterile sites. Conclusions: Though rare, extraintestinal C. difficile manifestations pose important clinical challenges. Better understanding of their mechanisms is essential for early recognition and appropriate management. Further research is warranted to define potential mechanisms and therapeutic approaches. Full article

Clostridioides difficile infection (CDI), the most common cause of nosocomial diarrhea, presents with a wide spectrum of clinical manifestations, ranging from mild diarrhea to severe, life-threatening conditions such as pseudomembranous colitis and toxic megacolon. In recent years, both the incidence and severity of CDI have increased, leading to a significant burden in terms of morbidity, mortality, and healthcare costs. We conducted a single-center, retrospective cohort study for 30 months at “Sf. Parascheva” Infectious Diseases Clinical Hospital Iași, in North Eastern Romania, aiming to assess the clinical and laboratory characteristics of CDI, as well as treatment approaches and their association with patient outcomes. A total of 534 patients were included during the study period, of whom 484 had favorable outcomes, while 50 have died of the disease. Fever (p = 0.007) and age over 65 (p = 0.001) were associated with prolonged hospitalization. Patients positive for both A and B toxins and GDH had the highest risk of recurrence (p = 0.020). Among comorbidities, obesity was the only condition significantly linked to recurrence (p = 0.001). In female patients over 65 years old, the probability of survival drops below 60% after 21 days of hospitalization, highlighting a critical risk factor in this population. These results underscore the importance of comprehensive risk assessment in CDI, particularly focusing on advanced age and comorbidities, to guide early therapeutic interventions, optimize patient management, and improve clinical outcomes among high-risk populations. Full article

Inflammatory bowel disease (IBD) in animals, a multifactorial gastrointestinal disorder marked by chronic inflammation, has increasingly been linked to Clostridioides difficile infections. Recognized for its pathogenic role in human pseudomembranous colitis, C. difficile is now emerging as a critical agent in veterinary medicine, particularly in livestock (e.g., cattle, pigs), companion animals (dogs, cats), and wildlife. Over the past five years, evidence has highlighted its association with IBD-like syndromes in animals, driven by toxin-mediated mechanisms (TcdA/TcdB), antibiotic-induced dysbiosis, and environmental spore transmission. This opinion article synthesizes recent findings on C. difficile’s zoonotic potential, diagnostic ambiguities (e.g., distinguishing colonization from active infection), and therapeutic challenges, including antibiotic resistance. We emphasize the urgent need for integrated One Health strategies to mitigate risks to animal and human health, advocating for improved surveillance, novel therapies, and interdisciplinary research. Full article

Clostridioides difficile Infection (CDI) continues to be a major cause of antibiotic-associated diarrhea and pseudomembranous colitis, fueled in large measure by virulence factors TcdA and TcdB. These giant glucosyltransferase toxins interfere with host cytoskeletal integrity and inflammatory signaling by inhibiting Rho GTPase; however, the detailed structural dynamics, receptor selectivity, and subcellular trafficking mechanisms remain in part unspecified. This review integrates recent insights from cryo-electron microscopy (cryo-EM) and X-ray crystallography to describe the quaternary architecture of TcdA/B, emphasizing conformational changes key to pore formation and endosomal escape. We also examine the genomic heterogeneity of hypervirulent C. difficile strains (e.g., ribotype 027), correlating toxin gene polymorphisms (e.g., tcdC mutations) with increased toxin production and virulence. Mechanistic explanations of toxin-driven inflammasome activation and epithelial barrier dysfunction are situated within host immune evasion mechanisms, including microbiota-derived bile acid regulation of toxin stability. Subsequent innovative therapeutic strategies, encompassing the utilization of engineered neutralizing antibodies that specifically target the autoprocessing domain alongside structure-guided small-molecule inhibitors, are subjected to a rigorous evaluation. By integrating structural biology, systems-level omics, and clinical epidemiology, this review establishes a comprehensive framework for understanding C. difficile toxin pathogenesis and guiding next-generation precision antimicrobials. Full article

Clostridioides difficile became one of the main causes of nosocomial infections in all clinical settings worldwide, especially among patients undergoing antibiotic therapy. The incidence and severity of C. difficile infections, from mild diarrhea to life-threatening pseudomembranous colitis, correlate with the spread of the hypervirulent binary toxin (CDT)-producing strains. The use of the real-time HRM-PCR method enables the identification of hypervirulent C. difficile strains directly in the diarrheal stool samples of patients suspected of being infected with this bacterium. For this purpose, the cdtA and cdtB genes encoding CDT subunits, as well as the species-specific gluD gene, were detected to identify the presence of this bacterium in the tested samples. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of the established method were also assessed. The obtained results were compared with the results of eazyplex^® C. difficile complete test (AmplexDiagnostics GmbH) based on the LAMP method, used in standard microbiological diagnostics. The values of the assessed diagnostic parameters for the detected genes ranged from 58.82% to 98.85%. The lowest value (58.82%) was obtained for the PPV of cdtB and the highest (98.85%) for the NPV of this gene. The real-time HRM-PCR method enables fast and simple detection of the investigated genes of hypervirulent C. difficile strains and, after careful optimization, may demonstrate high potential for usefulness in routine microbiological diagnostics. Full article

Clostridioides difficile is the main causative agent of antibiotic-associated diarrhea (AAD) in hospitals in the developed world. Both infected patients and asymptomatic colonized individuals represent important transmission sources of C. difficile. C. difficile infection (CDI) shows a large range of symptoms, from mild diarrhea to severe manifestations such as pseudomembranous colitis. Epidemiological changes in CDIs have been observed in the last two decades, with the emergence of highly virulent types and more numerous and severe CDI cases in the community. C. difficile interacts with the gut microbiota throughout its entire life cycle, and the C. difficile’s role as colonizer or invader largely depends on alterations in the gut microbiota, which C. difficile itself can promote and maintain. The restoration of the gut microbiota to a healthy state is considered potentially effective for the prevention and treatment of CDI. Besides a fecal microbiota transplantation (FMT), many other approaches to re-establishing intestinal eubiosis are currently under investigation. This review aims to explore current data on C. difficile and gut microbiota changes in colonized individuals and infected patients with a consideration of the recent emergence of highly virulent C. difficile types, with an overview of the microbial interventions used to restore the human gut microbiota. Full article

Clostridioides difficile, a Gram-positive anaerobic bacterium, is the leading cause of hospital-acquired antibiotic-associated diarrhea worldwide. The severity of C. difficile infection (CDI) varies, ranging from mild diarrhea to life-threatening conditions such as pseudomembranous colitis and toxic megacolon. Central to the pathogenesis of the infection are toxins produced by C. difficile, with toxin A (TcdA) and toxin B (TcdB) as the main virulence factors. Additionally, some strains produce a third toxin known as C. difficile transferase (CDT). Toxins damage the colonic epithelium, initiating a cascade of cellular events that lead to inflammation, fluid secretion, and further tissue damage within the colon. Mechanistically, the toxins bind to cell surface receptors, internalize, and then inactivate GTPase proteins, disrupting the organization of the cytoskeleton and affecting various Rho-dependent cellular processes. This results in a loss of epithelial barrier functions and the induction of cell death. The third toxin, CDT, however, functions as a binary actin-ADP-ribosylating toxin, causing actin depolymerization and inducing the formation of microtubule-based protrusions. In this review, we summarize our current understanding of the interaction between C. difficile toxins and host cells, elucidating the functional consequences of their actions. Furthermore, we will outline how this knowledge forms the basis for developing innovative, toxin-based strategies for treating and preventing CDI. Full article

Clostridioides difficile is a causative agent of antibiotic-associated diarrhea as well as pseudomembranous colitis. So far, all known bacteriophages infecting these bacteria are temperate, which means that instead of prompt lysis of host cells, they can integrate into the host genome or replicate episomally. While C. difficile phages are capable of spontaneous induction and entering the lytic pathway, very little is known about the regulation of their maintenance in the state of lysogeny. In this study, we investigated the properties of a putative major repressor of the recently characterized C. difficile phiCDKH01 bacteriophage. A candidate protein belongs to the XRE family and controls the transcription of genes encoding putative phage antirepressors, known to be involved in the regulation of lytic development. Hence, the putative major phage repressor is likely to be responsible for maintenance of the lysogeny. Full article

Clostridioides difficile infection (CDI) is an intestinal infection that causes morbidity and mortality and places significant burden and cost on the healthcare system, especially in recurrent cases. Antibiotic overuse is well recognized as the leading cause of CDI in high-risk patients, and studies have demonstrated that even short-term antibiotic exposure can cause a large and persistent disturbance to human colonic microbiota. The recovery and sustainability of the gut microbiome after dysbiosis have been associated with fewer CDI recurrences. Fecal microbiota transplantation (FMT) refers to the procedure in which human donor stool is processed and transplanted to a patient with CDI. It has been historically used in patients with pseudomembranous colitis even before the discovery of Clostridioides difficile. More recent research supports the use of FMT as part of the standard therapy of recurrent CDI. This article will be an in-depth review of five microbiome therapeutic products that are either under investigation or currently commercially available: Rebyota (fecal microbiota, live-jslm, formerly RBX2660), Vowst (fecal microbiota spores, live-brpk, formerly SER109), VE303, CP101, and RBX7455. Included in this review is a comparison of the products’ composition and dosage forms, available safety and efficacy data, and investigational status. Full article

Background: Clostridioides difficile infections (CDI) vary in severity from mild diarrhea to life-threatening conditions like pseudomembranous colitis or toxic megacolon, often leading to sepsis and death. The COVID-19 pandemic prompted changes in healthcare practices, potentially affecting CDI incidence, though reported data are inconclusive. We studied factors influencing CDI incidence and outcomes at a university hospital throughout the COVID-19 pandemic years. Methods: We conducted a retrospective study on all adult hospitalized CDI cases from 1 January 2020 to 31 December 2022 in Hospital Universitari de Sant Joan in Reus. We collected demographic information, comorbid conditions, and concurrent infections. Results: While overall CDI and COVID-19 rates decreased in 2022, a notable increase in CDI infections was observed among oncological patients and those undergoing some aggressive treatments, such as colonoscopies or gastroscopies. The prevalence of comorbidities remained unmodified, and there were declines in prior gastrointestinal surgeries and proton pump inhibitor prescriptions. Factors associated with patient fatality or prolonged hospitalization included older age, cancer, chronic kidney disease, higher Charlson and McCabe indices, elevated C-reactive protein, and low albumin concentrations. Conclusions: Our study shows the evolving landscape of CDI during the COVID-19 pandemic and emphasizes the impact of delayed diagnoses and treatments exacerbated by telemedicine adoption. Identified risk factors for CDI-related mortality or prolonged hospital stays underscore the importance of targeted interventions in high-risk populations. Full article

Clostridioides difficile is a bacterium responsible for a healthcare-associated gastrointestinal infection, primarily affecting people who have undergone prolonged antibiotic treatment or who have compromised immune systems. The CD is of particular concern due to its high recurrence rates and the potential for serious outcomes, including life-threatening conditions such as pseudomembranous colitis, septic shock, and all associated conditions. Since this infection is a disease associated with other health conditions, a general vision of the problems is necessary which aims to obtain a general overview of the manifestations that generally correlate with care. Clinical reasoning following the disease-clustering method is able to produce a categorization process by grouping the possible correlations of the various conditions or factors underlying diseases on the basis of certain similarities or common models. The clustering process is performed using data analysis techniques which, by statically correlating each other, give an exact dimension of all the information related to a particular disease. In the case of CD, reasoning based on disease clustering has better clarified the practices, appropriateness in infection control, judicious use of antibiotics, and research into therapeutic and preventive strategies. This review, taking advantage of the clustering strategy, aimed to analyze the contingent conditions of the infection under examination, to reduce the incidence and impact of CD, having as its mission the improvement of the results deriving from the contrast of all those correlated pathological conditions to healthcare for the improvement of public health. Full article

Clostridioides difficile (C. difficile), responsible for 15–25% of gastrointestinal infections, causes health problems mainly due to the toxic activity of toxins A and B (Tcds). These are responsible for its clinical manifestations, including diarrhea, pseudomembranous colitis, toxic megacolon and death, with a mortality of 5–30% in primary infection, that increase following relapses. Studies on Tcd-induced cell death have highlighted a key role of caspases, calpains, and cathepsins, with involvement of mitochondria and reactive oxygen species (ROS) in a complex signaling pathway network. The complex response in the execution of various types of cell death (apoptosis, necrosis, pyroptosis and pyknosis) depends on the amount of Tcd, cell types, and Tcd receptors involved, and could have as initial/precocious event the alterations in calcium homeostasis. The entities, peculiarities and cell types involved in these alterations will decide the signaling pathways activated and cell death type. Calcium homeostasis alterations can be caused by calcium influx through calcium channel activation, transient intracellular calcium oscillations, and leakage of calcium from intracellular stores. These increases in cytoplasmic calcium have important effects on all calcium-regulated molecules, which may play a direct role in several cell death types and/or activate other cell death effectors, such as caspases, calpains, ROS and proapoptotic Bcl-2 family members. Furthermore, some support for the possible role of the calcium homeostasis alteration in Tcd-induced cell death originates from the similarity with cytotoxic effects that cause pore-forming toxins, based mainly on calcium influx through plasma membrane pores. Full article

Clostridioides difficile infections cause severe symptoms ranging from diarrhea to pseudomembranous colitis due to the secretion of AB-toxins, TcdA and TcdB. Both toxins are taken up into cells through receptor-mediated endocytosis, autoproteolytic processing and translocation of their enzyme domains from acidified endosomes into the cytosol. The enzyme domains glucosylate small GTPases such as Rac1, thereby inhibiting processes such as actin cytoskeleton regulation. Here, we demonstrate that specific pharmacological inhibition of Hsp70 activity protected cells from TcdB intoxication. In particular, the established inhibitor VER-155008 and the antiemetic drug domperidone, which was found to be an Hsp70 inhibitor, reduced the number of cells with TcdB-induced intoxication morphology in HeLa, Vero and intestinal CaCo-2 cells. These drugs also decreased the intracellular glucosylation of Rac1 by TcdB. Domperidone did not inhibit TcdB binding to cells or enzymatic activity but did prevent membrane translocation of TcdB’s glucosyltransferase domain into the cytosol. Domperidone also protected cells from intoxication with TcdA as well as CDT toxin produced by hypervirulent strains of Clostridioides difficile. Our results reveal Hsp70 requirement as a new aspect of the cellular uptake mechanism of TcdB and identified Hsp70 as a novel drug target for potential therapeutic strategies required to combat severe Clostridioides difficile infections. Full article

Clostridioides difficile infection (CDI) is one of the most common hospital-acquired infections. Its incidence has increased during the last decade in the community among individuals with no previous risk factors; however, morbidity and mortality are still considered high in elderly patients. Oral Vancomycin and Fidaxomicin are the first lines of treatment for CDI. The systemic bioavailability of oral Vancomycin is thought to be undetectable due to its poor absorption in the gastrointestinal tract; therefore, routine monitoring is not warranted. Only 12 case reports were found in the literature that described adverse reactions associated with oral Vancomycin and its related risk factors. We present a case of a 66-year-old gentleman with severe CDI and acute renal failure who was started on oral Vancomycin upon admission. On day five of treatment, he developed leukocytosis associated with neutrophilia, eosinophilia, and atypical lymphocytes, with no evidence of active infection. Three days later, he developed a pruritic maculopapular rash in more than 50% of his body surface area. Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) was ruled out since the patient only had three inclusion criteria for this diagnosis. No clear inciting agent was found. Oral Vancomycin was stopped and supportive treatment was supplied for a presumed Vancomycin-induced allergic reaction. The patient had an excellent response, with complete resolution of the rash and leukocytosis in less than 48 h. By reporting this case, we want to raise awareness among clinicians to remember that, albeit rare, oral Vancomycin can be the cause of adverse drug reactions in patients with severe illnesses. Full article