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)-1ß, 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-1ß and IFNγ in the muscle or spleen of Str. A1-infected birds and IL-1ß 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.

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.

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.

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.

60-year-old male with rapidly progressive pneumocephalus caused by Clostridium septicum in the setting of an occult colonic adenocarcinoma.

BACKGROUND: Disseminated Clostridium septicum infection is an uncommon complication associated with malignancies, particular colonic adenocarcinoma. The organism appears to preferentially colonize large masses in rare individuals and subsequently seed the blood via mucosal ulceration. This has rarely been reported to lead to central nervous system infection and, in several cases, rapidly progressive pneumocephalus. In the few cases reported, this was a universally fatal condition. The current case adds to the reports of this extremely rare complication and provides a unique and complete clinicopathologic characterization with autopsy examination, microscopy, and molecular testing. CASE PRESENTATION: A 60-year-old man with no known past medical history was discovered having seizure-like activity and stroke-like symptoms. Blood cultures turned positive after six hours. Imaging revealed a large, irregular cecal mass as well as 1.4 cm collection of air in the left parietal lobe that progressed to over 7 cm within 8 h. By the following morning, the patient had lost all neurologic reflexes and died. Post-mortem examination revealed brain tissue with multiple grossly evident cystic spaces and intraparenchymal hemorrhage, while microscopic exam showed diffuse hypoxic-ischemic injury and gram-positive rods. Clostridium septicum was identified on blood cultures and was confirmed in paraffin embedded tissue from the brain by 16 S ribosomal sequencing and from the colon by C. septicum specific PCR. CONCLUSIONS: C. septicum is an anaerobic, gram-positive rod that can become invasive and is strongly associated with gastrointestinal pathology including colonic adenocarcinomas. Central nervous system infection with rapidly progressive pneumocephalus is a rarely reported and universally fatal complication of disseminated C. septicum infection.

Fulminant endogenous panophthalmitis caused by Clostridium septicum infection / Panoftalmite endógena fulminante por infecção por Clostridium septicum

ABSTRACT We report an unusual case of fulminant endogenous Clostridium septicum panophthalmitis. A 74-year-old male patient presented with sudden amaurosis in the right eye, which in a few hours, evolved into an orbital cellulitis, endophthalmitis, anterior segment ischemia, and secondary perforation of the eye. A complete diagnostic study, which included cranial and orbital contrast-enhanced computed tomography scan, contrast-enhanced magnetic resonance imaging, blood cultures, and complete blood work, were performed. No causal agent was identified. Clostridium septicum infection caused fulminant gaseous panophthalmitis. Despite broad-spectrum antibiotic treatment, evisceration of the eyeball was necessary. The extension study showed a colon adenocarcinoma as the origin of the infection. Clostridium septicum panophthalmitis is a rare but aggressive orbital infection. This infection warrants the identification of a neoplastic process in the gastrointestinal tract in many cases not previously described.

RESUMO Este é o relato de um caso incomum de panoftalmite endógena fulminante por Clostridium septicum. Um paciente do sexo masculino, 74 anos, apresentou amaurose súbita no olho direito, que em poucas horas evoluiu para celulite orbitária, endoftalmite, isquemia do segmento anterior e perfuração secundária do olho. Foi realizado um estudo diagnóstico completo, que incluiu uma tomografia computadorizada com contraste cranial e orbital, um exame de ressonância magnética, hemocultura e hemograma completo. Nenhum agente causal foi identificado. A infecção por Clostridium septicum causou uma panoftalmite gasosa fulminante. Apesar do tratamento com antibióticos de amplo espectro, foi necessário eviscerar o globo ocular. O estudo de seguimento mostrou um adenocarcinoma de cólon como a origem da infecção. A panoftalmite por Clostridium septicum é um tipo raro, mas muito agressivo de infecção orbitária. Essa infecção deve sugerir a busca por um processo neoplásico no trato gastrointestinal, em muitos casos não diagnosticado anteriormente.

Detection and molecular characterization of Clostridium perfringens, Paeniclostridium sordellii and Clostridium septicum from lambs and goat kids with hemorrhagic abomasitis in Turkey.

BACKGROUND: The pathogenic Clostridia cause neurotoxic, histotoxic and enterotoxic infections in humans and animals. Several Clostridium species have been associated with abomasitis in ruminants. The present study aimed to investigate the frequency, and the presence of virulence genes, of Clostridium perfringens, Paeniclostridium sordellii and Clostridium septicum in lambs and goat kids with hemorrhagic abomasitis. RESULTS: A total of 38 abomasum samples, collected from lambs and goat kids of 1 week to 1 month of age in different farms located in eastern Turkey between 2021 and 2022, were evaluated by histopathology, culture and PCR. At necropsy, the abomasum of the animals was excessively filled with caseinized content and gas, and the abomasum mucosa was hemorrhagic in varying degrees. In histopathological evaluation, acute necrotizing hemorrhagic inflammation was noted in abomasum samples. The examination of swab samples by culture and PCR revealed that C. perfringens type A was the most frequently detected species (86.84%) either alone or in combination with other Clostridium species. P. sordellii, C. perfringens type F and C. septicum were also harboured in the samples, albeit at low rates. Beta2 toxin gene (cpb2) was found in three of C. perfringens type A positive samples. CONCLUSION: It was suggested that vaccination of pregnant animals with toxoid vaccines would be beneficial in terms of protecting newborn animals against Clostridial infections. This study investigated the presence of clostridial toxin genes in abomasal samples for the first time in Turkey.

Fulminant endogenous panophthalmitis caused by Clostridium septicum infection.

We report an unusual case of fulminant endogenous Clostridium septicum panophthalmitis. A 74-year-old male patient presented with sudden amaurosis in the right eye, which in a few hours, evolved into an orbital cellulitis, endophthalmitis, anterior segment ischemia, and secondary perforation of the eye. A complete diagnostic study, which included cranial and orbital contrast-enhanced computed tomography scan, contrast-enhanced magnetic resonance imaging, blood cultures, and complete blood work, were performed. No causal agent was identified. Clostridium septicum infection caused fulminant gaseous panophthalmitis. Despite broad-spectrum antibiotic treatment, evisceration of the eyeball was necessary. The extension study showed a colon adenocarcinoma as the origin of the infection. Clostridium septicum panophthalmitis is a rare but aggressive orbital infection. This infection warrants the identification of a neoplastic process in the gastrointestinal tract in many cases not previously described.

Clostridium septicum brain abscess.

We present a previously well woman in her 70s who was admitted for 2 weeks of progressively worsening abdominal pain, high fever and drowsiness. She was eventually diagnosed with Clostridium septicum brain abscess, meningoencephalitis and ventriculitis. The diagnosis was challenging as cerebrospinal fluid cultures were negative and a microbiological diagnosis was only obtained on brain biopsy. Despite early initiation of antibiotics that would have been effective against C. septicum, her central nervous system (CNS) infection progressed, and she eventually succumbed to the infection. Infections with C. septicum are typically fulminant and associated with high mortality. In a patient with a CNS infection and concomitant abdominal manifestations, infection with C. septicum should be considered.

[Colonic perforation and sepsis associated with Clostridium septicum as clinical presentation of colon cancer]. / Perforación colónica y sepsis fulminante asociada a Clostridium septicum como presentación de un cáncer de colon.

The association between some bacterial infections and colon cancer is well documented. The most described is Streptococcus bovis infection. Another bacteria related to intestinal neoplasms is Clostridium septicum. We present the case of a 62-year-old man who consulted for abdominal pain associated with diarrhea and fever. A computed tomography scan of the abdomen and pelvis was performed, which revealed thickening of the cecum walls with an apparent break in continuity at its free edge. An exploratory laparotomy was performed which confirmed the presence of peritonitis and cecal perforation. A right hemicolectomy and terminal ileostomy were performed. The histopathological study revealed the presence of signet ring cell type adenocarcinoma associated with ischemia. The blood cultures results demonstrated the presence of C. septicum. The patient died due to fulminant sepsis.

Extended emphysematous aortitis of the ascending aorta: An unusual fatal presentation of aortic valve endocarditis due to Clostridium Septicum.

N/A.

Perforación colónica y sepsis fulminante asociada a Clostridium septicum como presentación de un cáncer de colon / Colonic perforation and sepsis associated with Clostridium septicum as clinical presentation of colon cancer

Resumen La asociación entre algunas infecciones bacterianas y cáncer de colon está bien documentada. La más descrita es la infección por Streptococcus bovis. Otra bacteria relacionada a neoplasias intestinales es Clostridium septicum. Presentamos el caso clínico de un varón de 62 años que consultó por dolor abdominal, diarrea y fiebre. Se realizó una tomografía computada de abdomen y pelvis que evidenció un engrosamiento de las paredes del ciego con una aparente solución de continuidad en su borde libre. En una laparotomía exploradora se confirmó la presencia de peritonitis y perforación cecal, siendo sometido a una hemicolectomía derecha e ileostomía terminal. El estudio histopatológico reveló la presencia de un adenocarcinoma de tipo células en anillo de sello asociado a isquemia. Los hemocultivos fueron positivos a C. septicum. El paciente falleció por una sepsis fulminante.

Abstract The association between some bacterial infections and colon cancer is well documented. The most described is Streptococcus bovis infection. Another bacteria related to intestinal neoplasms is Clostridium septicum. We present the case of a 62-year-old man who consulted for abdominal pain associated with diarrhea and fever. A computed tomography scan of the abdomen and pelvis was performed, which revealed thickening of the cecum walls with an apparent break in continuity at its free edge. An exploratory laparotomy was performed which confirmed the presence of peritonitis and cecal perforation. A right hemicolectomy and terminal ileostomy were performed. The histopathological study revealed the presence of signet ring cell type adenocarcinoma associated with ischemia. The blood cultures results demonstrated the presence of C. septicum. The patient died due to fulminant sepsis.

Clostridium septicum foot gangrene associated with colorectal cancer.

INTRODUCTION: Since the second half of the 20th century, an association between the occurrence of Clostridium septicum and Streptococcus gallolyticus infections in patients with colorectal cancer has been described in specialist literature. Infections are manifested by bacteremia, septic embolism, cellulitis, myonecrosis, and gas gangrene of the limbs. MATERIAL AND METHODS: The authors present a case of a rare association between lower limb gangrene caused by the septic embolization of a Clostridium septicum infection and malignancy of colon ascendens in a polymorbid patient. Gangrene of the lower limb led to septic shock requiring acute amputation treatment. After managing the acute condition, the patient was operated on for a malignant colon tumour. DISCUSSION: The process of carcinogenesis often takes years and is almost asymptomatic. The occurrence of S. bovis/S. equinus (SBSEC) and C. septicum bacteremia, respectively, is relatively rare, but their presence is often associated with the occurrence of malignancy, most often of the lower gastrointestinal tract. This paraneoplastic symptom may be the first manifestation of a malignant disease. The effect of exotoxins can lead to sepsis or even septic shock with a mortality of 48-56%. CONCLUSION: Clostridium septicum and Streptococcus gallolyticus infections are rare in clinical practice. However, their presence can be a first paraneoplastic symptom, and therefore the doctor should look for a possible oncological disease when they are detected. The main diagnostic methods include colonoscopy and imaging, especially CT scan.

Clostridium septicum α-toxin activates the NLRP3 inflammasome by engaging GPI-anchored proteins.

Clostridium species are a group of Gram-positive bacteria that cause diseases in humans, such as food poisoning, botulism, and tetanus. Here, we analyzed 10 different Clostridium species and identified that Clostridium septicum, a pathogen that causes sepsis and gas gangrene, activates the mammalian cytosolic inflammasome complex in mice and humans. Mechanistically, we demonstrate that α-toxin secreted by C. septicum binds to glycosylphosphatidylinositol (GPI)-anchored proteins on the host plasma membrane, oligomerizing and forming a membrane pore that is permissive to efflux of magnesium and potassium ions. Efflux of these cytosolic ions triggers the activation of the innate immune sensor NLRP3, inducing activation of caspase-1 and gasdermin D, secretion of the proinflammatory cytokines interleukin-1ß and interleukin-18, pyroptosis, and plasma membrane rupture via ninjurin-1. Furthermore, α-toxin of C. septicum induces rapid inflammasome-mediated lethality in mice and pharmacological inhibition of the NLRP3 inflammasome using MCC950 prevents C. septicum-induced lethality. Overall, our results reveal that cytosolic innate sensing of α-toxin is central to the recognition of C. septicum infection and that therapeutic blockade of the inflammasome pathway may prevent sepsis and death caused by toxin-producing pathogens.

Systematic literature review and meta-analysis of Clostridium septicum aortitis.

BACKGROUND: Clostridium septicum bacteremia is often associated with occult malignancies (approximately 80%), especially of the right colon. Furthermore, inflammation of the aortic wall can rapidly lead to aneurysm induction through bacterial seeding into atheromatous lesions with consecutive life-threatening rupture. We summarize all published data on this rare and lethal disease to evaluate therapeutic approaches and give valid treatment recommendations because there are no guidelines. METHODS: A systematic review of the literature was conducted screening EMBASE and MEDLINE databases following the PRISMA guidelines with search period from first description to August 25, 2021. RESULTS: There were 72 cases of C septicum aortitis reported in 64 publications. Endovascular aortic repair (EVAR) was performed in a minority of patients (n = 6) unfit for surgery but lacked long-term survivors. Antibiotic treatment was beneficial in a bridge to surgery concept, but up to now harbored a 6-month mortality rate of 100% (median overall survival, 0.5 months) when no additional aortic repair was performed. Open aortic repair was the only potential curative approach but was accompanied with a 90-day-mortality of 26.7% (4/15). CONCLUSIONS: Open aortic repair combined with perioperative antibiotic treatment should be offered to all patients as the only potentially curative approach. If applicable, resection of a coexisting colonic tumor should be performed after successful aortic repair. Alternatively, long-term antibiotic treatment can be offered to patients unfit for surgery in a palliative setting. Endovascular aortic repair has been performed on a minority of patients with a high risk for stent graft infection and should remain a salvage strategy when therapeutic pressure demands acute intervention in patients unfit for surgery.