Clostridium Septicum Research Articles

Fatal course of afulminant gas gangrene of the right hemithorax

The full clinical picture of agas gangrene infection is an absolute rarity. The mechanism of development can be either traumatic or spontaneous (e.g., hematogenous seeding in occult colon carcinoma). In particular, the rare pathogen Clostridium septicum appears to be associated with spontaneously occurring gas gangrene. Diabetes mellitus is asignificant risk factor. The mortality rate of the disease is around 50%, even with maximum therapeutic efforts, and the course of the disease is fulminant in the majority of cases. Initial symptoms are unspecific and make early diagnosis difficult. Treatment consists of high-dose antibiotics in combination with radical surgical debridement and, if necessary, supplementary hyperbaric oxygen therapy.

Gas gangrene with Clostridium septicum in a neutropenic patient.

Gas gangrene is a rare presentation of a necrotizing fasciitis, caused by Clostridium perfringens, C. septicum and other clostridial species. With its rapid progression it is a potentially life-threatening infection, that poses as a challenge in the clinical management requiring an interdisciplinary approach.Here we present a 62-year-old woman, who developed neutropenic fever while undergoing chemotherapy for triple negative breast cancer. She presented with a high fever, reporting little pain in her left thigh accompanied by redness and induration locally. Subsequently the patient developed pain and redness of the back of the left hand. The initial findings suggested cellulitis and immediate empiric treatment with intravenous meropenem was started. Despite the antibiotic treatment the patient rapidly developed septic shock along with progression of the local infection. Emergency surgical debridement revealed extensive necrosis of the soft tissues including extensive myonecrosis of the thigh. On the left hand an extensive debridement was performed, the left lower limb could not be preserved and exarticulation of the left hip was required. Microbiologically C. septicum was isolated in different samples, confirming gas gangrene. As there was no local entry portal on the skin, hematogenous seeding from intestinal translocation in this neutropenic patient was suspected. The empiric antibiotic treatment was tailored to intravenous penicillin and complemented with clindamycin for toxin inhibition. Following radical debridement and antibiotic treatment, the patient could be stabilized. After repetitive debridement wound closure was achieved and the patient was discharged for rehabilitation. Antibiotic treatment was continued for four weeks.This rare case of gas gangrene in a neutropenic patient shows the complexity in the diagnostic and therapeutic management of necrotizing soft tissue infections in immunocompromised patients. It particularly highlights the importance of an interdisciplinary management with fast recognition of the disease and rapid, if needed radical, surgical debridement as well as tailored antibiotic treatment for a successful outcome.

S2751 A Case of Clostridium septicum Endophthalmitis as the First Presenting Sign of Colon Cancer

S2751 A Case of Clostridium septicum Endophthalmitis as the First Presenting Sign of Colon Cancer

Periaortic gas and signs of dissection of amycotic aneurysm in the descending thoracic aorta due to Clostridium septicum

The case of 92-year-old male with ahistory of sepsis due to Clostridium septicum is described. Since the bacteria were also found at the site of joint aspiration, the patient underwent knee prosthesis removal. Due to the association between colorectal cancer and Clostridium septicum, acolonoscopy was performed. An adenocarcinoma was extracted in situ. At 5months, the patient presented again with shortness of breath, acute retrosternal pain and fever. CT revealed amycotic aneurysm of the descending aorta with StanfordB dissection and periaortic gas. Due to the fragility of the patient, conservative treatment was initiated.

Exotoxins secreted by Clostridium septicum induce macrophage death: Implications for bacterial immune evasion mechanisms at infection sites

The induction of macrophage death is considered a potential mechanism by which components secreted by Clostridium septicum are used to evade the innate immune response and cause tissue damage. This study aimed to determine the effects of partially purified fractions of extracellular proteins secreted by C. septicum on the death of mouse peritoneal macrophages. Elicited mouse peritoneal macrophages were incubated with partially purified fractions of proteins secreted by C. septicum into the culture medium. After incubation, the protein fraction with a molecular weight ≥100 kDa caused significant cell death in macrophages, altered cell morphology, increased the expression of markers of apoptosis and autophagy, and increased the expression (protein and mRNA) of IL-10 and TNFα. Our data suggest that the proteins secreted by C. septicum (MW, ≥100 kDa) induce cell death in macrophages by promoting autophagy-triggered apoptosis. This study may contribute to our understanding of the molecular mechanism of immune evasion by C. septicum at the infection site.

Clostridium septicum manifests a bile salt germinant response mediated by Clostridioides difficile csp gene orthologs

Clostridium septicum infections are highly predictive of certain malignancies in human patients. To initiate infections, C. septicum spores must first germinate and regain vegetative growth. Yet, what triggers the germination of C. septicum spores is still unknown. Here, we observe that C. septicum germinates in response to specific bile salts. Putative bile salt recognition genes are identified in C. septicum based on their similarity in sequence and organization to bile salt-responsive csp genes in Clostridioides difficile. Inactivating two of these csp orthologs (cspC-82 and cspC-1718) results in mutant spores that no longer germinate in the presence of their respective cognate bile salts. Additionally, inactivating the putative cspBA or sleC genes in C. septicum abrogates the germination response to all bile salt germinants, suggesting that both act at a convergent point downstream of cspC-82 and cspC-1718. Molecular dynamics simulations show that both CspC-82 and CspC-1718 bear a strong structural congruence with C. difficile’s CspC. The existence of functional bile salt germination sensors in C. septicum may be relevant to the association between infection and malignancy.

Colorectal cancer and association with anaerobic bacteraemia: A Danish nationwide population-based cohort study

We aimed to identify specific anaerobic bacteria causing bacteraemia and a subsequent diagnosis of colorectal cancer. A nationwide population-based cohort study, which included all episodes of defined specific anaerobic bacteraemia from 2010 (5,534,738 inhabitants) through 2020 (5,822,763 inhabitants) and all cases of colorectal cancer diagnosed from 2010 through 2021 in Denmark. We calculated the incidence and risk of colorectal cancer after bacteraemia with specific anaerobic bacteria using Escherichia coli bacteraemia as reference. Nationwide data on colorectal cancer and specific anaerobic bacteraemia (100% complete, representing 11,124 episodes). The frequencies of colorectal cancer within one year following anaerobic bacteraemia were higher for species, which almost exclusively reside in the colon, such as Phocaeicola vulgatus/dorei (5.5%), Clostridium septicum (24.2%), and Ruminococcus gnavus (4.6%) compared to 0.6% in 50,650 E. coli bacteraemia episodes. Bacteroides spp. had a subhazard ratio for colorectal cancer of 3.9 (95% confidence interval [CI], 3.0 to 5.1) and for Clostridium spp. it was 8.9 (95% CI, 6.7 to 11.8, with C. septicum 50.0 [95% CI, 36.0 to 69.5]) compared to E. coli (reference). This nationwide study identified specific colorectal cancer-associated anaerobic bacteria, which almost exclusively reside in the colon. Bacteraemia with these bacteria could be an indicator of colorectal cancer.

Confinement energy landscape classification reveals membrane receptor nano-organization mechanisms

The cell membrane organization has an essential functional role through the control of membrane receptor confinement in micro- or nanodomains. Several mechanisms have been proposed to account for these properties, although some features have remained controversial, notably the nature, size, and stability of cholesterol- and sphingolipid-rich domains or lipid rafts. Here, we probed the effective energy landscape acting on single-nanoparticle-labeled membrane receptors confined in raft nanodomains— epidermal growth factor receptor (EGFR), Clostridium perfringens ε-toxin receptor (CPεTR), and Clostridium septicum α-toxin receptor (CSαTR)—and compared it with hop-diffusing transferrin receptors. By establishing a new analysis pipeline combining Bayesian inference, decision trees, and clustering approaches, we systematically classified single-protein trajectories according to the type of effective confining energy landscape. This revealed the existence of only two distinct organization modalities: confinement in a quadratic energy landscape for EGFR, CPεTR, and CSαTR (A), and free diffusion in confinement domains resulting from the steric hindrance due to F-actin barriers for transferrin receptor (B).The further characterization of effective confinement energy landscapes by Bayesian inference revealed the role of interactions with the domain environment in cholesterol- and sphingolipid-rich domains with (EGFR) or without (CPεTR and CSαTR) interactions with F-actin to regulate the confinement energy depth. These two distinct mechanisms result in the same organization type (A). We revealed that the apparent domain sizes for these receptor trajectories resulted from Brownian exploration of the energy landscape in a steady-state-like regime at a common effective temperature, independently of the underlying molecular mechanisms. These results highlight that confinement domains may be adequately described as interaction hotspots rather than rafts with abrupt domain boundaries. Altogether, these results support a new model for functional receptor confinement in membrane nanodomains and pave the way to the constitution of an atlas of membrane protein organization.

Immunization of turkeys with Clostridium septicum alpha toxin-based recombinant subunit proteins can confer protection against experimental Clostridial dermatitis.

Clostridial dermatitis (CD), caused by Clostridium septicum, is an emerging disease of increasing economic importance in turkeys. Currently, there are no effective vaccines for CD control. Here, two non-toxic domains of C. septicum alpha toxin, namely ntATX-D1 and ntATX-D2, were identified, cloned, and expressed in Escherichia coli as recombinant subunit proteins to investigate their use as potential vaccine candidates. Experimental groups consisted of a Negative control (NCx) that did not receive C. septicum challenge, while the adjuvant-only Positive control (PCx), ntATX-D1 immunization (D1) and ntATX-D2 immunization (D2) groups received C. septicum challenge. Turkeys were immunized subcutaneously with 100 μg of protein at 7, 8 and 9 weeks of age along with an oil-in-water nano-emulsion adjuvant, followed by C. septicum challenge at 11 weeks of age. Results showed that while 46.2% of birds in the PCx group died post-challenge, the rate of mortality in D1- or D2-immunization groups was 13.3%. The gross and histopathological lesions in the skin, muscle and spleen showed that the disease severity was highest in PCx group, while the D2-immunized birds had significantly lower lesion scores when compared to PCx. Gene expression analysis revealed that PCx birds had significantly higher expression of pro-inflammatory cytokine genes in the skin, muscle and spleen than the NCx group, while the D2 group had significantly lower expression of these genes compared to PCx. Peripheral blood cellular analysis showed increased frequencies of activated CD4+ and/or CD8+ cells in the D1 and D2-immunized groups. Additionally, the immunized turkeys developed antigen-specific serum IgY antibodies. Collectively, these findings indicate that ntATX proteins, specifically the ntATX-D2 can be a promising vaccine candidate for protecting turkeys against CD and that the protection mechanisms may include downregulation of C. septicum-induced inflammation and increased CD4+ and CD8+ cellular activation.

Development of real-time PCR assay for quantitative detection of Clostridium septicum

Cellulitis is an important disease in commercial turkey farms associated with significant economic loss. Although the etiology of cellulitis is not fully elucidated, Clostridium septicum (C. septicum) is one of the main causes of this infectious disease. In this study, we report the development of a quantitative real-time PCR (qRT PCR) assay targeting the alpha-toxin gene (csa), which involves a prior 15-cyle PCR using a nested pair of primers to increase the detection sensitivity. Additionally, the TaqMan probe was employed to increase the target-specificity of the assay. The performance of our nested qRT-PCR assay was evaluated using Clostridium isolates from turkey farms, representing both septicum and non-septicum species, as well as sponge swab samples from turkey farms. Our step-by-step development of the assay showed that the csa gene is a suitable target for specific detection of C. septicum strains and that the inclusion of nested PCR step significantly increased the detection sensitivity of the final qRT PCR assay. The performance of the assay was also validated by a high correlation of the threshold cycle numbers of the qRT PCR assay with the relative abundance of C. septicum read counts in 16S rRNA gene microbiota profiles of the C. septicum-containing samples from turkey farms.

16s RNA-based metagenomics reveal previously unreported gut microbiota associated with reactive arthritis and undifferentiated peripheral spondyloarthritis.

Reactive arthritis (ReA) provides a unique opportunity to comprehend how a mucosal infection leads to inflammatory arthritis at a distant site without the apparent invasion of the pathogen. Unfortunately, conventional stool cultures after ReA provide limited information, and there is a dearth of metagenomic studies in ReA. The objective of this study was to identify gut microbiota associated with the development of ReA. Patients with ReA or undifferentiated peripheral spondyloarthritis (UpSpA) were included if they presented within 4 weeks of the onset of the current episode of arthritis. Metagenomic DNA was extracted from the stools of these patients and of 36 age- and sex-similar controls. Sequencing and analysis were done using a standard 16S ribosomal pipeline. Of 55 patients, there was no difference between the gut microbiota of postdiarrheal ReA(n = 20) and of upSpA (n = 35). Comparing the gut microbiota of patients vs healthy controls, the patients had significantly higher alpha and beta diversity measures. After stringency filters, Proteobacteria had high abundance while Firmicutes had lesser as compared with the controls. Six families were overexpressed in patients, while another five were overexpressed in controls. Sixteen genera and 18 species were significantly different between patients and controls. At the species level there was strong association of Staphylococcus aureus, Clostridium septicum Klebsiella pneumoniae, Escherichia coli, Empedobacter brevis, Roseburia hominis, Bacillus velezensis, and Crassaminicella with ReA. The microbiota of classical gut-associated ReA and upSpA is similar. Patients have higher diversities in their gut microbiota compared with healthy controls. Both known and previously unreported species associated with ReA/upSpA were identified.

Characterization of immune responses and immunopathology in turkeys experimentally infected with clostridial dermatitis-producing strains of Clostridium septicum

Clostridium septicum is one of the major causative agents of clostridial dermatitis (CD), an emerging disease of turkeys, characterized by sudden deaths and necrotic dermatitis. Despite its economic burden on the poultry industry, the immunopathological changes and pathogen-specific immune responses are poorly characterized. Here, we used three strains of C. septicum, namely Str. A1, Str. B1 and Str. C1, isolated from CD field outbreaks, to experimentally infect turkeys to evaluate local (skin and muscle) and systemic (spleen) pathological and immunological responses. Results showed that while all three strains produced an acute disease, Str. A1 and B1 caused significantly higher mortality when compared to Str. C1. Gross and histopathology evaluation showed that birds infected with Str. A1 and B1 had severe inflammatory, edematous, granulomatous and necrotic lesions in the skin, muscle and spleen, while these lesions produced by Str. C1 were relatively less severe and mostly confined to skin and/or muscle. Immune gene expression in these tissues showed that Str. B1-infected birds had significantly higher expression of interleukin (IL)−1β, IL-6 and interferon (IFN)γ genes compared to uninfected control, suggesting a robust inflammatory response both locally as well as systemically. The transcription of IL-1β and IFNγ in the muscle or spleen of Str. A1-infected birds and IL-1β in the skin of Str. C1-infected group was also significantly higher than control. Additionally, Str. A1 or B1-infected groups also had significantly higher IL-4 transcription in these tissues, while birds infected with all three strains developed C. septicum-specific serum antibodies. Furthermore, splenic cellular immunophenotyping in the infected turkeys showed a marked reduction in CD4+ cells. Collectively, it can be inferred that host responses against C. septicum involve an acute inflammatory response along with antibody production and that the disease severity seem to depend on the strain of C. septicum involved in CD in turkeys.

Genome sequence of Clostridium septicum strain WW106, isolated from influent wastewater at a research center with multiple-species research animal facilities.

Clostridium septicum is an anaerobic Gram-positive rod-shaped bacterial pathogen known as a lethal causative agent of progressive gas gangrene in animals and humans. We report the 3.43-Mbp genome sequence of C. septicum strain WW106, isolated from influent wastewater at a research center with multiple-species laboratory animal facilities.

Bacteria Associated with Kitchen Surface in Some Selected Areas in Sokoto State, Nigeria

Contamination of kitchen utensils and their role as a source or microbial reservoir is now becoming a major concern in addressing food hygiene and safety. This study was carried out to isolate and identify bacteria associated with kitchen surfaces in some selected areas in Sokoto State, Nigeria. The swab sticks were collected from the Kitchen surface in Arkilla, Lowcoast, Mabera, Minnanata and Runjin Sambo. Samples collected were isolated and characterized using microscopy and biochemical tests. The most frequently isolated bacteria were Citrobacter freundi with (16%), followed by Staphylococcus cohnii with (12%). Clostridium fallax, Bacillus cereus, Salmonella sp., Staphylococcus saccharolyticus, Clostridium botulinum and vibrio cholera, had (8%) each. Clostridium septicum, Staphylococcus haemolyticus, Lactobacillus acidophilus, Staphylococcus intermedius, Salmonella para typhi A, Shigella specie, Staphylococcus xerosis, Clostridium butyricum had (4%) each. Also, the highest mean count of 1.18x105cfu/ml/50cm2 was observed from bacteria isolated in Arkilla area. The implication of this finding is that potentially pathogenic bacteria like Staphylococcus, Salmonella, Shigella and Vibrio species may be of public health concern. The need for disinfection of kitchen and covering the utensils use in kitchen is now very important.

Immune-mediated hematological disease in dogs is associated with alterations of the fecal microbiota: a pilot study

BackgroundThe dog is the most popular companion animal and is a valuable large animal model for several human diseases. Canine immune-mediated hematological diseases, including immune-mediated hemolytic anemia (IMHA) and immune thrombocytopenia (ITP), share many features in common with autoimmune hematological diseases of humans. The gut microbiome has been linked to systemic illness, but few studies have evaluated its association with immune-mediated hematological disease. To address this knowledge gap, 16S rRNA gene sequencing was used to profile the fecal microbiota of dogs with spontaneous IMHA and ITP at presentation and following successful treatment. In total, 21 affected and 13 healthy control dogs were included in the study.ResultsIMHA/ITP is associated with remodeling of fecal microbiota, marked by decreased relative abundance of the spirochete Treponema spp., increased relative abundance of the pathobionts Clostridium septicum and Escherichia coli, and increased overall microbial diversity. Logistic regression analysis demonstrated that Treponema spp. were associated with decreased risk of IMHA/ITP (odds ratio [OR] 0.24–0.34), while Ruminococcaceae UCG-009 and Christensenellaceae R-7 group were associated with increased risk of disease (OR = 6.84 [95% CI 2–32.74] and 8.36 [95% CI 1.85–71.88] respectively).ConclusionsThis study demonstrates an association of immune-mediated hematological diseases in dogs with fecal dysbiosis, and points to specific bacterial genera as biomarkers of disease. Microbes identified as positive or negative risk factors for IMHA/ITP represent an area for future research as potential targets for new diagnostic assays and/or therapeutic applications.

Characteristics of the intestinal microbiota in patients with colorectal cancer

AIM: to study the intestinal microbiota and identify its characteristic features in patients with colorectal cancer.PATIENTS AND METHODS: in this study, the composition of the intestinal microbiota in patients with colorectal cancer was analyzed, while the comparison group consisted of patients with non-inflammatory bowel diseases.RESULTS: previous studies have shown the possible role of enterococci and some types of clostridia in stimulating oncogenic processes and, on the contrary, the vital role of lactobacilli and bifidobacteria in intestinal homeostasis maintaining. The aim of this study was to compare the gut microbiota composition in colorectal cancer patients and non-inflammatory bowel diseases patients gut microbita. The proportion of enterococci was increased in patients with colorectal cancer (12.7% in the study group and 7.6% in the control group) on the contrary the proportion of bifidobacteria and obligate anaerobes was decreased (1.5% in the study group and 4% in the control groups) and (3.3 % of the study group and 9.7% in the control group) respectively. Decrease of the microbiota biodiversity was observed for the patients with colorectal cancer that was calculated by the Shannon diversity Index (4.46 in the study group and 4.8 in the control group), also two-fold increase of Pseudomonas aeruginosa share (2.2% in the study group and 1.1% in the control group) was found for this cohort, Clostridium septicum was isolated only from patients with colorectal cancer.CONCLUSION: this study results suggest the diagnostic significance of the species diversity of the intestinal microbiota.

A Narrative Literature Review on Sepsis: A Primary Manifestation of Colorectal Neoplasm.

Sepsis and colorectal cancer (CRC) exhibit a complex relationship that warrants further exploration. This review delves into the interplay of factors between sepsis and CRC, uncovering shared pathophysiological traits and potential bacterial associations. Understanding these connections could pave the way for earlier diagnosis, improved management, and enhanced outcomes in CRC patients. The role of immune system dysfunction, hypoalbuminemia, and specific microbial imbalances, such as Streptococcus bovis and Clostridium septicum, are discussed. Recognizing sepsis in CRC patients is crucial for timely intervention, and tailored approaches encompassing antibiotic therapy, source control measures, and cancer treatment are essential for comprehensive care. Monitoring biomarkers and ratios can provide valuable insights into complications and overall health outcomes. A multidisciplinary approach involving various specialists is necessary to address the global burden of CRC and its association with sepsis while exploring novel interventions, such as fecal microbiota transplantation and personalized care. We conducted a thorough search using reputable databases such as PubMed, Scopus, and Google Scholar to investigate the connection between sepsis and CRC. We refined our search terms, utilized sidebar filters, and examined references in selected articles. This meticulous process helped us create a comprehensive literature review and gain valuable insights into this relationship.

A non-toxic recombinant Clostridium septicum α toxin induces protective immunity in mice and rabbits

Clostridium septicum alpha toxin (CSA) plays significant roles in ruminant's braxy. Genetically engineered CSA has been shown to function as a potential vaccine candidate in the prevention of the disease caused by Clostridium septicum. In the present study, we synthesized a non-toxic recombinant, rCSAm4/TMD by introducing four amino acid substitutions (C86L/N296A/H301A/W342A) and 11-amino-acid deletion (residues 212 to 222). Compared to recombinant CSA, rCSAm4/TMD showed no cytotoxicity to MDCK cells and was not fatal to mice. Moreover, rCSAm4/TMD could protect immunized mice against 5 × mouse LD100 (100% lethal dose) of crude CSA without obvious pathological change. Most importantly, rabbits immunized with rCSAm4/TMD produced high titers of neutralizing antibodies which protected the rabbits against crude CSA challenge. These data suggest that genetically detoxified rCSAm4/TMD is a potential subunit vaccine candidate against braxy.

Antibiotic resistance and biofilm-forming ability of α-toxin-positive Clostridium septicum isolates worsen patient prognosis.

A total of, 78 Clostridium septicum (CLSE) isolates were screened for genes encoding: α-toxin, flagellin, and resistance to vancomycin (VANg). The isolates were also tested for their ability to form biofilm and their antibiotic susceptibility. All isolates were positive for α-toxin and flagellin genes. However, only 19 isolates (24.3%) showed prevalence for VANg. We observed the strongest capacity to form a biofilm (100%) in isolates from patients with oncologic or septic and febrile diagnoses. This percentage was also very high in patients with colitis and gastrointestinal hemorrhage (72.7%). No less than 43 isolates showed antibiotic resistance, and 21 were multidrug-resistant (MDR). Interestingly, our studies showed a correlation between antibiotic resistance and biofilm formation. A statistically significant difference was observed between biofilm-forming MDR isolates and those with low/no biofilm-forming ability. However, the most impressive observation was the correlation with mortality rate. While the overall mortality rate for CLSE infections was 16.7% (13/78), the mortality rate for patients infected with MDR isolates forming biofilm moderately or strongly reached 38.1% (8/21). This number increased even further when only infections with the biofilm-forming VANg-positive isolates were considered (61.5%; 8/13). Therefore, the ability of a VANg-positive CLSE isolate to form a biofilm has been suggested as a biomarker of poor prognosis.

Evaluation of Clostridium septicum hemolytic activity, administration route, and dosage volume of a clostridial dermatitis (cellulitis) bacterin-toxoid on humoral immune response in commercial turkeys

Clostridial cellulitis or dermatitis affects commercial turkey flocks, primarily as they approach market age. In the field, this disease has been effectively controlled with antibiotics, but alternatives to antibiotics are needed. Bacterin-toxoid vaccination programs have been shown to prevent clostridial diseases in other species, including humans. Results from previous field studies indicate that vaccination with an experimental whole-cell Clostridium septicum (CS) bacterin-toxoid oil emulsion vaccine reduced clostridial dermatitis-associated mortality and antibiotic usage for some commercial turkey flocks, but vaccination was not always efficacious. To improve vaccine efficacy, studies were conducted to optimize the antigenic component of the experimental vaccine and to determine the appropriate antigen to adjuvant ratio, route, and volume for vaccine administration. It was determined that the phase of culture at time of formalin inactivation played a key role in serum antibody titer and larger volume vaccine doses produced higher serum antibody immune response regardless of antigen:adjuvant formulation ratio or route of injection. No significant differences (P > 0.05) were found between formulation ratios or between the subcutaneous and tail head injection sites. Based on these results, we propose to look further into the relationship between culture phase and antigenic components produced by CS under different culture conditions.