Phagocyte extracellular traps formation contributes to host defense against Clostridium perfringens infection

Clostridium perfringens (C. perfringens) is an important Gram-positive anaerobic spore-forming pathogen that provokes life-threatening gas gangrene and acute enterotoxaemia, although it colonizes as a component of the symbiotic bacteria in humans and animals. However, the mechanisms by which C. perfringens is cleared from the host remains poorly understood, thereby impeding the development of novel strategies for control this infection. Here, we uncover a beneficial effect of extracellular traps (ETs) formation on bacterial killing and clearance by phagocytes. C. perfringens strain ATCC13124, and wild-type isolates CP1 and CP3 markedly trigger ETs formation in macrophages and neutrophils. As expected, visualization of DNA decorated with histone, myeloperoxidase (MPO) and neutrophils elastase (NE) in C. perfringens-triggered classical ETs structures. Notably, the bacteria-induced ETs formation is an ERK1/2-, P38 MAPK-, store-operated calcium entry (SOCE)-, NADPH oxidase-, histone-, NE-, and MPO-dependent process, and is independent of LDH activity. Meanwhile, the defect of bactericidal activity is mediated by impairing ETs formation in phagocytes. Moreover, In vivo studies indicated that degradation of ETs by DNase I administration leads to a defect in the protection against experimental gas gangrene, with higher mortality rates, exacerbated tissue damage, and more bacterial colonization. Together, these results suggest that phagocyte ETs formation is essential for the host defense against C. perfringens infection.

Clostridium perfringens α-toxin impairs granulocyte colony-stimulating factor receptor-mediated granulocyte production while triggering septic shock

During bacterial infection, granulocyte colony-stimulating factor (G-CSF) is produced and accelerates neutrophil production from their progenitors. This process, termed granulopoiesis, strengthens host defense, but Clostridium perfringens α-toxin impairs granulopoiesis via an unknown mechanism. Here, we tested whether G-CSF accounts for the α-toxin-mediated impairment of granulopoiesis. We find that α-toxin dramatically accelerates G-CSF production from endothelial cells in response to Toll-like receptor 2 (TLR2) agonists through activation of the c-Jun N-terminal kinase (JNK) signaling pathway. Meanwhile, α-toxin inhibits G-CSF-mediated cell proliferation of Ly-6G+ neutrophils by inducing degradation of G-CSF receptor (G-CSFR). During sepsis, administration of α-toxin promotes lethality and tissue injury accompanied by accelerated production of inflammatory cytokines in a TLR4-dependent manner. Together, our results illustrate that α-toxin disturbs G-CSF-mediated granulopoiesis by reducing the expression of G-CSFR on neutrophils while augmenting septic shock due to excess inflammatory cytokine release, which provides a new mechanism to explain how pathogenic bacteria modulate the host immune system.

[Life-threatening intrauterine infection with Clostridium perfringens]

In this case report, a 40-year-old woman with a history of a uterine leiomyoma presented with abdominal pain and fever. Initially, her symptoms were associated with a bleeding from an ovarian cyst seen on a CT scan of the abdomen showing free intraperitoneal fluid surrounding the internal genitals. Meanwhile, her blood cultures came out positive for Clostridium perfringens, and her condition deteriorated despite intravenous antibiotics. A new CT scan revealed intrauterine gas development. A laparotomy was performed with removal of the internal genitals, and the patient improved on continuous antibiotics.

Concurrent Host-Pathogen Transcriptional Responses in a Clostridium perfringens Murine Myonecrosis Infection

To obtain an insight into host-pathogen interactions in clostridial myonecrosis, we carried out comparative transcriptome analysis of both the bacterium and the host in a murine Clostridium perfringens infection model, which is the first time that such an investigation has been conducted. Analysis of the host transcriptome from infected muscle tissues indicated that many genes were upregulated compared to the results seen with mock-infected mice. These genes were enriched for host defense pathways, including Toll-like receptor (TLR) and Nod-like receptor (NLR) signaling components. Real-time PCR confirmed that host TLR2 and NLRP3 inflammasome genes were induced in response to C. perfringens infection. Comparison of the transcriptome of C. perfringens cells from the infected tissues with that from broth cultures showed that host selective pressure induced a global change in C. perfringens gene expression. A total of 33% (923) of C. perfringens genes were differentially regulated, including 10 potential virulence genes that were upregulated relative to their expression in vitro These genes encoded putative proteins that may be involved in the synthesis of cell wall-associated macromolecules, in adhesion to host cells, or in protection from host cationic antimicrobial peptides. This report presents the first successful expression profiling of coregulated transcriptomes of bacterial and host genes during a clostridial myonecrosis infection and provides new insights into disease pathogenesis and host-pathogen interactions.IMPORTANCEClostridium perfringens is the causative agent of traumatic clostridial myonecrosis, or gas gangrene. In this study, we carried out transcriptional analysis of both the host and the bacterial pathogen in a mouse myonecrosis infection. The results showed that in comparison to mock-infected control tissues, muscle tissues from C. perfringens-infected mice had a significantly altered gene expression profile. In particular, the expression of many genes involved in the innate immune system was upregulated. Comparison of the expression profiles of C. perfringens cells isolated from the infected tissues with those from equivalent broth cultures identified many potential virulence genes that were significantly upregulated in vivo These studies have provided a new understanding of the range of factors involved in host-pathogen interactions in a myonecrosis infection.

Interventions for treating gas gangrene

BACKGROUND

Gas gangrene is a rapidly progressive and severe disease that results from bacterial infection, usually as the result of an injury; it has a high incidence of amputation and a poor prognosis. It requires early diagnosis and comprehensive treatments, which may involve immediate wound debridement, antibiotic treatment, hyperbaric oxygen therapy, Chinese herbal medicine, systemic support, and other interventions. The efficacy and safety of many of the available therapies have not been confirmed.

OBJECTIVES

To evaluate the efficacy and safety of potential interventions in the treatment of gas gangrene compared with alternative interventions or no interventions.

SEARCH METHODS

In March 2015 we searched: The Cochrane Wounds Group Specialized Register, The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, Science Citation Index, the China Biological Medicine Database (CBM-disc), the China National Knowledge Infrastructure (CNKI), and the Chinese scientific periodical database of VIP INFORMATION (VIP) for relevant trials. We also searched reference lists of all identified trials and relevant reviews and four trials registries for eligible research. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

We selected randomized controlled trials (RCTs) and quasi-RCTs that compared one treatment for gas gangrene with another treatment, or with no treatment.

DATA COLLECTION AND ANALYSIS

Independently, two review authors selected potentially eligible studies by reviewing their titles, abstracts and full-texts. The two review authors extracted data using a pre-designed extraction form and assessed the risk of bias of each included study. Any disagreement in this process was solved by the third reviewer via consensus. We could not perform a meta-analysis due to the small number of studies included in the review and the substantial clinical heterogeneity between them, so we produced a narrative review instead.

MAIN RESULTS

We included two RCTs with a total of 90 participants. Both RCTs assessed the effect of interventions on the 'cure rate' of gas gangrene; 'cure rate' was defined differently in each study, and differently to the way we defined it in this review.One trial compared the addition of Chinese herbs to standard treatment (debridement and antibiotic treatment; 26 participants) against standard treatment alone (20 participants). At the end of the trial the estimated risk ratio (RR) of 3.08 (95% confidence intervals (CI) 1.00 to 9.46) favoured Chinese herbs. The other trial compared standard treatment (debridement and antibiotic treatment) plus topical hyperbaric oxygen therapy (HBOT; 21 participants) with standard treatment plus systemic HBOT (23 participants). There was no evidence of difference between the two groups; RR of 1.10 (95% CI 0.25 to 4.84). For both comparisons the GRADE assessment was very low quality evidence due to risk of bias and imprecision so further trials are needed to confirm these results.Neither trial reported on this review's primary outcomes of quality of life, and amputation and death due to gas gangrene, or on adverse events. Trials that addressed other therapies such as immediate debridement, antibiotic treatment, systemic support, and other possible treatments were not available.

AUTHORS' CONCLUSIONS

Re-analysis of the cure rate based on the definition used in our review did not show beneficial effects of additional use of Chinese herbs or topical HBOT on treating gas gangrene. The absence of robust evidence meant we could not determine which interventions are safe and effective for treating gas gangrene. Further rigorous RCTs with appropriate randomisation, allocation concealment and blinding, which focus on cornerstone treatments and the most important clinical outcomes, are required to provide useful evidence in this area.

Clinical Features of Non-clostridial Gas Gangrene and Risk Factors for In-hospital Mortality

OBJECTIVE

To examine the clinical features of patients with non-clostridial gas gangrene (NCGG) at our hospital and identify risk factors for in-hospital mortality.

METHODS

This study included 24 patients with NCGG who were hospitalized in our medical facility from April 2005 to March 2015. The clinical features of NCGG were reviewed, and the characteristics of 6 patients who died in hospital and 18 who survived were compared to investigate risk factors.

RESULTS

The median time from symptom onset to hospital arrival was 168 h. The causative agent was Klebsiella pneumoniae in 8.3% and mixed infection in 91.7%; 83.3% of patients had diabetes, and one patient had no obvious underlying disease. The site of infection was the neck in 4.2%, the thoracoabdominal wall and retroperitoneum in 12.5% each, the back in 33.3%, the buttocks in 25.0%, the perineum in 20.8%, and the extremities in 45.8%. Retroperitoneal infection, blood lactate ≥ 4.0 mmol/L, and Japanese Association for Acute Medicine disseminated intravascular coagulation (DIC) score ≥ 4 on emergency department (ED) arrival were significantly higher in non-survivors than in survivors.

CONCLUSION

NCGG tends to develop in patients with diabetes, and in-hospital mortality rates are still high. Retroperitoneal infection, hyperlactatemia, and DIC on ED arrival are risk factors for in-hospital mortality.

[Toxins of Clostridium perfringens as a natural and bioterroristic threats]

Clostridium perfringens is absolutely anaerobic rod-shaped, sporeforming bacterium. The morbidity is connected with producing toxins. Depending on the type of toxin produced Clostridium perfringens can be divided into five serotypes:A-E. Under natural conditions, this bacterium is responsible for local outbreaks of food poisoning associated with eating contaminated food which which was improperly heat treated. Some countries with lower economic level are endemic foci of necrotizing enteritis caused by Clostridium perfringens. The bacterium is also a major cause of gas gangrene. It is a disease, associated with wound infection, with potentially fatal prognosis in the case of treatment's delays. In the absence of early radical surgery, antibiotic therapy and (if available) hyperbaric treatment leads to the spread of toxins in the body causing shock, coma and death. Due to the force of produced toxins is a pathogen that poses a substrate for the production of biological weapons. It could potentially be used to induce outbreaks of food poisoning and by missiles contamination by spore lead to increased morbidity of gas gangrene in injured soldiers. C. perfringens types B and D produce epsilon toxin considered to be the third most powerful bacterial toxin. Because of the ability to disperse the toxin as an aerosol and a lack of methods of treatment and prevention of poisoning possible factors it is a potential tool for bioterrorism It is advisable to continue research into vaccines and treatments for poisoning toxins of C. perfringens.

Clostridium perfringens gas gangrene at a wrist intravenous line insertion

A patient admitted to the intensive care unit for management of hypotension following a multiple medications overdose subsequently deteriorated rapidly with sepsis. A cannula site was noted to be bruised, swollen and erythematous and the X-ray demonstrated gas sitting within the tissues surrounding the metacarpal bones. The patient was referred to the orthopaedic surgeons and quickly taken for debridement of the affected area and fasciotomies of the forearm. Microbiological investigation confirmed Clostridium perfringens to be present in multiple fluid samples taken from the affected site.

[New insight from basic research of Clostridium perfringens alpha-toxin]

Clostridium perfringens causes gas gangrene with inflammatory myopathies and infrequently septicemia associated with massive intravascular hemolysis. The microorganism is known to produce a variety of toxins and enzymes that are responsible for severe myonecrotic lesions. Notably, alpha-toxin, which possesses hemolytic, necrotic and lethal activities, and phospholipase C and sphingomyelinase activities, is an important agent for the diseases. The cytokine storm induced by alpha-toxin, mainly the release of TNF-alpha, plays an important role in the death and massive hemolysis. The toxin-induced release of TNF-alpha from neutrophils and macrophages is dependent on the activation of ERK1/2 signal transduction via TrkA receptor. In addition, 14- and 15-membered macrolides specifically block the toxin-induced events through the activation of neutrophils and macrophages.

A rare diagnostic challenge in acute appendicitis: a case report

Although rare, acute appendicitis presenting as a remote abscess with cellulitis in the gluteal region, retroperitoneal region, groin, or thigh does occur and may present a diagnostic challenge. We report a case of a 78-year-old woman presenting with an extensive gas-forming abscess in the right gluteal region secondary to perforated appendicitis without significant gastrointestinal symptoms. Computed tomography (CT) demonstrated a retroperitoneal abscess extending along the sacropelvic surface of the ilium to the subcutaneous tissue. Subsequently, laparotomy revealed retrocecal appendicitis perforated at the base of the cecum, and contained in the retroperitoneum without any signs of peritonitis. This case not only represents an unusual manifestation of acute appendicitis, but also alerts us to the importance of anatomical considerations when interpreting disease extent with imaging. In the differential diagnosis of gluteal or upper thigh abscesses, the rare possibility of perforated acute appendicitis should be considered.

[Spontaneous Clostridium infection--often a post-mortem diagnosis]

Infections with Clostridium species occur very seldom but then often as a lethal disease. They are mainly associated with trauma, surgery and malignancies, but can also occur with dermal and intestinal infections, burns and septic abortion. The development of gas gangrene is insidious and progression is very rapid. So it may stay unrealized until death and is often diagnosed only at autopsy.

Endogenous gas gangrene after laparoscopic cholecystectomy

Clostridial gas gangrene of the abdominal wall is rare, and it is usually associated with organ perforation, immunosuppression or gastrointestinal malignancies. In this paper we present a case of fulminant, endogenous gas gangrene in a 58-year old diabetic female with arterial hypertension and atherosclerosis, following uneventful laparoscopic cholecystectomy. She developed gas gangrene of the abdominal wall 12-hours after cholecystectomy and died 24-hours after the onset of the first symptoms, in spite of treatment.

[Microbiological diagnosis of gas gangrene caused by Clostridium septicum (a clinical case)]

Microscopy of gram-stained impression smears is used for the rapid diagnosis of microorganisms in the wound. The shin tissues of patient P. with suspected gas gangrene of lower extremity soft tissues were microscopically found to have gram-positive spore-forming bacteria that were morphologically similar to C. bifermentans that were identified as C. septicum on cultural diagnosis. The pathogenic C. septicum strain spores were likely to be formed in the macroorganism upon exposure of the pathogen to a patient's defense factors and to a package of therapeutic measures. Microbiological data should be used only in combination with clinical and instrumental findings and the results of other laboratory studies when the optimal technology is chosen to treat gas infection. By keeping in mind that there may be clostridial gangrene in the patients and the experience of clinicians and bacteriologists may be insufficient in diagnosing this pathology, it is necessary to strengthen the training of physicians in the diagnosis of this pathology.

[Massive intravascular hemolysis secondary to sepsis due to Clostridium perfringens]

Massive hemolysis secondary to sepsis caused by Clostridium perfringens is a rare entity but appears fairly often in the literature. In nearly all published reports, the clinical course is rapid and fatal. We describe the case of a 75-year-old woman with diabetes who was admitted with symptoms consistent with acute cholecystitis. Deteriorating hemodynamics and laboratory findings were consistent with intravascular hemolysis, coagulation disorder, and renal failure. Gram-positive bacilli of the Clostridium species were detected in blood along with worsening indicators of hemolysis. In spite of antibiotic and surgical treatment, hemodynamic support and infusion of blood products, the patient continued to decline and died in the postoperative recovery unit 14 hours after admission. Mortality ranges from 70% to 100% in sepsis due to Clostridium perfringens, and risk of death is greater if massive hemolysis is present, as in the case we report. Only a high degree of clinical suspicion leading to early diagnosis and treatment can improve the prognosis. This bacterium should therefore be considered whenever severe sepsis and hemolysis coincide.

Ruptured tuboovarian abscess and septic shock with Clostridium perfringens in a postmenopausal woman: a case report

BACKGROUND

Clostridium perfringens is the most common causative organism of gas gangrene, a necrotizing infection of soft tissue classically associated with traumatic injuries. Recently, awareness of its occurrence in spontaneous nontraumatic contexts has been increasing. The authors report an unusual case of nontraumatic/spontaneous C perfringens gas gangrene localized to the adnexae.

CASE

A 55-year-old woman presented with abdominal complaints and had surgery because the computed tomographic finding of air in the abdomen led to a preoperative diagnosis of perforated bowel. An infected, draining, right tuboovarian complex and infected left tube were removed. The patient had a stormy postoperative course and was ultimately diagnosed with C perfringens infection/sepsis; she had to be readmitted over a month after discharge for drainage of a pelvic abscess, also due to clostridial infection. The patient ultimately underwent hysterectomy with removal of remaining adnexa. The hysterectomy specimen revealed endometrial carcinoma.

CONCLUSION

C perfringens can cause adnexal infection in the absence of trauma. Diagnosis may be difficult. Timely, aggressive surgical and medical therapy is imperative. When such cases occur, malignancy should be suspected.

[Microbiology and management of gaseous gangrene:the Sichuan experience of 20 earthquake cases]

Wound secretion from 20 patients with gaseous gangrene was collected for Gram staining, bacterial culture and drug sensitivity tests. The results indicated that gaseous gangrene was caused by the co-infection of both aerobic and anaerobic bacteria. Gram-negative bacilli were slightly more common than other aerobic bacteria in gaseous gangrene wound, which was different from the findings of ordinary gaseous gangrene.

Microbiology of salt rising bread

Salt rising bread (SRB) is an Appalachian traditional bread made without yeast, using a starter derived from flour, milk and potatoes. The "rising agent" has been identified as Clostridium perfringens, not salt, and is presumably derived from the environment. Although no cases of illness have been attributed to SRB, C. perfringens type A is a common cause of food poisoning from meats and gravies. Other C. perfringens isolates may cause enteritis necroticans (pig-bel disease) and gas gangrene. Past research documents that pathogenic strains derived from wounds may be used to produce bread and that bacteria isolated from this bread retain their pathogenicity. SRB starter samples were cultured at the University of Pittsburgh and abundant C. perfringens, type A grew out of all samples. However none of the cultures were positive for enterotoxin and thus would be unlikely to cause human food borne disease. While this does not preclude the possibility of other starter mixes containing enteropathogenic strains, the baking process appears to reduce bacterial contamination to safe levels and SRB has not been implicated in causing any human disease.

Civilian gas gangrene: a clinical challenge

Gas gangrene due to clostridia infections is commonly seen in war injuries and is much less commonly seen in civilian life. When such problems do occur, they present a challenge to the surgeon due to the associated high morbidity and mortality associated. A case is presented where a patient developed gas gangrene in a limb consequent to trauma that had been treated surgically. It is vital to make a correct diagnosis at the earliest to limit disease progression and to avoid complications.

Puerperal Clostridium perfringens Sepsis in a Patient with Granulocytopenia

We present a lethal case of fulminant puerperal sepsis with massive hemolysis after cesarean section in a patient with intermittent granulocytopenia.

Microbiology and management of soft tissue and muscle infections

This review summarizes the microbiological aspects and management of soft tissue and muscle infections. The infections presented are: impetigo, folliculitis, furunculosis and carbuncles, cellulitis, erysipelas, infectious gangrene (includes necrotizing fasciitis or streptococcal gangrene, gas gangrene or clostridium myonecrosis, anaerobic cellulites, progressive bacterial synergistic gangrene, synergistic necrotizing cellulitis or perineal phlegmon, gangrenous balanitis, and gangrenous cellulitis in the immunocompromised patient), secondary bacterial infections complication skin lesions, diabetic and other chronic superficial skin ulcers and subcutaneous abscesses and myositis. These infections often occur in body sites or in those that have been compromised or injured by foreign body, trauma, ischemia, malignancy or surgery. In addition to Group A streptococci and Staphylococcus aureus, the indigenous aerobic and anaerobic cutaneous and mucous membranes local microflora usually is responsible for polymicrobial infections. These infections may occasionally lead to serious potentially life-threatening local and systemic complications. The infections can progress rapidly and early recognition and proper medical and surgical management is the cornerstone of therapy.

Gangrenous Clostridium perfringens infection and subsequent wound management in a rhesus macaque (Macaca mulatta)

A 10-y-old female rhesus macaque presented acutely with 3 large (diameter, greater than 4 cm), malodorous, ulcerogangrenous skin wounds on the left caudal thigh and calf. Limb radiographs revealed free gas infiltrating deep tissues, and histologic examination confirmed myonecrosis. Clostridium perfringens, Staphylococcus aureus, and Prevotella intermedia were isolated from the wounds. Antimicrobials, analgesics, and aggressive debridement of necrotic skin and muscle resulted in immediate clinical improvement of the primate. At 1 wk prior to presentation, the animal had received several intramuscular injections in close proximity to the site of infection. Repeated intramuscular injections through excrement-contaminated skin possibly contributed to the pathogenesis of infection. Continued therapy consisted of biweekly wound debridement and nonadherent bandage changes for 7 wk. The macaque regained full use of the affected leg and remains in good physical condition at our facility. Our management of this case led to improvements in training regarding intramuscular injection practices in our macaque colony. This case study is the first report of Clostridium perfringens myonecrosis in a laboratory nonhuman primate. We discuss various methodologies for the diagnosis and treatment of necrotizing clostridial infections.

A case of Clostridium septicum spontaneous gas gangrene

Severe skin and soft tissue infections (SSTIs) are often life-threatening emergencies that require a rapid diagnosis. Gas gangrene is one of the most fulminant types of SSTI and is usually caused by Clostridium perfringens' contamination of an open wound. Although gas gangrene is usually associated with fecally contaminated wounds, "spontaneous" cases occur and are most commonly caused by Clostridium (C.) septicum. We report a case of spontaneous gas gangrene caused by C. septicum that only became manifest while the patient was being monitored in the emergency department. We also review the diagnosis and treatment aspects of this entity.

Clostridium tertium isolated from gas gangrene wound; misidentified as Lactobacillus spp initially due to aerotolerant feature

Clostridium tertium has been increasingly reported as a human pathogen. This organism is an aerotolerant Gram-positive rod that is often mistaken for other organisms, such as Lactobacillus or Bacillus species. We describe a case of a patient with a history of intravenous drug use presenting to UCLA-Olive View Medical Center with gas gangrene of both upper extremities. The organism was initially misidentified as a Lactobacillus species on aerobic culture plates. However, terminal spore formation was detected in this isolate on a sub-cultured anaerobic culture plate and this isolate was confirmed as C. tertium biochemically and genetically by 16S rDNA sequencing. Additional DNA cloning libraries made from the formalin-fixed specimen revealed Peptoniphilus species and an uncultured Clostridium clone, but not C. tertium. C. tertium might be a causative organism of gas-producing myonecrosis but such an association has never been described. Clinicians should be aware of the phenomenon of aerotolerance of some anaerobes and need to clarify the identification of organisms if the clinical picture does not fit the isolated organism.

The role of neutrophils and monocytic cells in controlling the initiation of Clostridium perfringens gas gangrene

Clostridium perfringens is a common cause of the fatal disease gas gangrene (myonecrosis). Established gas gangrene is notable for a profound absence of neutrophils and monocytic cells (phagocytes), and it has been suggested that the bactericidal activities of these cells play an insignificant role in controlling the progression of the infection. However, large inocula of bacteria are needed to establish an infection in experimental animals, suggesting phagocytes may play a role in inhibiting the initiation of gangrene. Examination of tissue sections of mice infected with a lethal (1 x 10(9)) or sublethal (1 x 10(6)) inoculum of C. perfringens revealed that phagocyte infiltration in the first 3 h postinfection was inhibited with a lethal dose but not with a sublethal dose, indicating that exclusion of phagocytes begins very early in the infection cycle. Experiments in which mice were depleted of either circulating monocytes or neutrophils before infection with C. perfringens showed that monocytes play a role in inhibiting the onset of gas gangrene at intermediate inocula but, although neutrophils can slow the onset of the infection, they are not protective. These results suggest that treatments designed to increase monocyte infiltration and activate macrophages may lead to increased resistance to the initiation of gas gangrene.

Infection and musculoskeletal conditions: Infectious myositis

Infectious myositis, an infection of the skeletal muscle(s), is uncommon. This clinical entity may be caused by viral, bacterial, fungal, and parasitic pathogens. Viral etiologies typically cause diffuse myalgias and/or myositis, whereas bacteria and fungi usually lead to a local myositis which may be associated with sites compromised by trauma or surgery and are more common among immunocompromised patients. Localized collections within the muscles are referred to as pyomyositis. Other pyogenic causes of myositis include gas gangrene, group A streptococcal myonecrosis, and other types of non-clostridial myonecrosis. Early recognition and treatment of these conditions are necessary as they may rapidly become life-threatening.

Non-Clostridial Gas Gangrene of the Neck and Mediastinum

Herein we report a case of gas gangrene of the neck and mediastinum in a poorly managed Type II diabetic with concomitant chronic renal failure and a recent history of mucormycosis. Despite the burden of co-morbidities and the gravity of the illness, the patient was successfully treated and remained free of complications in the long term.

[Clostridial sepsis and gas gangrene of the abdominal wall after cholecystectomy]

Clostridial sepsis is a rare complication after intraabdominal operations, mostly fatal. According to our knowledge only two papers describing clostridial sepsis as postoperative complication in 4 patients were published in the Czech literature, only one of them survived. Authors present a case report of patient operated on for cholecystolithiasis and obstructive icterus where within 48 hours after cholecystectomy the clostridial sepsis and gas gangrene of the abdominal wall developed and that were successfuly managed.

Clostridium perfringens phospholipase C-induced platelet/leukocyte interactions impede neutrophil diapedesis

Clostridium perfringens gas gangrene is a fulminant necrotizing infection in which inflammatory cells are notably absent from infected tissues but are often massed within adjacent vessels. It has been shown that C. perfringens phospholipase C (PLC) stimulates formation of large intravascular platelet/leukocyte complexes and that PLC-induced activation of platelet gpIIbIIIa plays a major role. In vivo, such aggregates contribute to microvascular thrombosis and ischaemic necrosis of tissue. However, the effects of adherent platelets on neutrophil diapedesis have not been established. The present work investigated (1) the contribution of platelet P-selectin (CD62P) to PLC-induced cellular complex formation and (2) the effects of platelet adhesion on neutrophil diapedesis. The effects of anti-gpIIbIIIa and anti-CD62P strategies on PLC-induced complex formation were measured by flow cytometry and followed by light microscopy. Both platelet gpIIbIIIa and CD62P contributed to the formation of platelet/leukocyte complexes. Specifically, gpIIbIIIa mediated the formation of large platelet/platelet aggregates that were tethered to the leukocyte principally via CD62P. Neutrophil diapedesis, quantified by a transendothelial cell migration assay and visualized by electron microscopy, was significantly reduced (>60%) by the adherence of large platelet aggregates. It was concluded that the absence of a tissue inflammatory response in C. perfringens gas gangrene is due, in part, to impaired neutrophil mobility caused by large aggregates of adherent platelets induced by PLC. Further, an adjunctive immunotherapeutic strategy targeting both gpIIbIIIa and CD62P may improve the tissue inflammatory response, prevent vascular occlusion, maintain tissue viability, and reduce the need for radical amputation in patients with clostridial gas gangrene.

Clostridium septicum infections in children: a case report and review of the literature

Clostridium myonecrosis is a rare and deadly infection that progresses very rapidly; thus, prompt diagnosis and treatment is vital. In adults, clostridial myonecrosis used to be a well-known complication of war wounds. Today, it is usually seen in settings of trauma, surgery, malignancy, skin infections/burns, and septic abortions. More recently, cases of nontraumatic or spontaneous clostridial myonecrosis have been reported in both adults and children. Clostridium perfringens and Clostridium septicum are responsible for the majority of the clinically relevant infections. Higher mortality rates are seen when C septicum is the causative agent. Here we present a child who survived a severe case of C septicum myonecrosis involving both abdominal and thoracic cavities. This rare infection has a high mortality rate and might be easily misdiagnosed in children, even by experienced clinicians, because of its nonspecific presentation. We also review all reported pediatric cases of C septicum infection and myonecrosis and discuss the surgical and medical interventions associated with improved survival. We identified a total of 47 cases of C septicum infection; of these, 22 (47%) were cases of C septicum associated with myonecrosis. Several factors, if available, were analyzed for each case: age, gender, infection location, previous diagnoses, presenting signs and symptoms, neutropenia, gross pathology of the colon, antibiotic use, surgical intervention, and final outcome. We found that conditions related with C septicum infection in children can be grouped into 3 major categories: patients with neutrophil dysfunction; patients with associated bowel ischemia; and patients with a history of trauma. Malignancies were found in 49% of the cases, cyclic or congenital neutropenia in 21%, hemolytic-uremic syndrome in 11%, structural bowel ischemia in 4%, and local extremity trauma in 6%. In addition, 6% of the cases had no known underlying disorder. Abdominal symptoms including vomiting, diarrhea, blood per rectum, abdominal pain, anorexia, and/or acute abdomen, were reported in 85% of the children. Fever was also a common finding. The mainstay of treatment for C septicum infection was parenteral antibiotics and/or surgical intervention. The mortality rate for children with C septicum infection and myonecrosis was 57% and 59%, respectively. Although 82% of all cases received antibiotics, only 43% underwent therapeutic surgical intervention. Several clinical factors were found to be associated with improved survival. Only 35% of the children with gastrointestinal tract involvement survived, compared with 86% of the children without gastrointestinal tract involvement. The survival rates for other conditions ranged from 0% to 50%. One hundred percent survival was reported in patients with no previously diagnosed conditions and those with infections resulting from trauma to the extremities. All survivors received antibiotic treatment, compared with only 68% of the nonsurvivors. Most survivors (84%) underwent therapeutic surgical intervention, compared with only 12% of nonsurvivors. Other treatments were used adjunctively, including hyperbaric oxygen, granulocyte colony-stimulating factor, granulocyte transfusions, and intravenous immunoglobulin. C septicum infections in children are often fatal; thus, one needs to have a high index of suspicion in at-risk patients. This review describes who these patients are, their clinical presentation, and the therapeutic strategies associated with improved survival.

Retroperitoneal gas gangrene after colonoscopic polypectomy without bowel perforation in an otherwise healthy individual: report of a case

BACKGROUND

Abdominal gas gangrene caused by clostridia species is rare and usually associated with organ perforation, immune suppression, or advanced malignoma.

CASE REPORT

A 61-year-old man was admitted with severe back pain 1 day after uncomplicated colonoscopic polypectomy. With the exception of preexisting minor depression, the patient had been previously in excellent health. The computed tomography scan showed retroperitoneal emphysema in the left psoas muscle. During exploratory laparotomy, a spreading retroperitoneal phlegmon with pneumoretroperitoneum and a secondary peritonitis were found. A macroscopic perforation of the gut, particularly at the polypectomy sites was excluded. After the operation, the patient evolved in a septic shock condition and had pulmonary failure. Before hyperbaric oxygen therapy could be employed, the patient died. The autopsy showed a massive gas gangrene of the retroperitoneum caused by Clostridium perfringens, but no macroscopic bowel perforation was detected.

RESULTS

This is the first report of a case of gas gangrene after uncomplicated polypectomy without macroscopic perforation in an otherwise healthy individual. A microperforation due to mucosal defect after polypectomy was most likely the entry point for the bacteria.

CONCLUSION

We conclude that clostridial myonecrosis should be considered in unclear abdominal infections, even if the patient's history is not typical as in the present case.

[The influence of AMPs from HaCaT keratinocytes on some bacteria strains derived from skin changes]

The aim of this study was to evaluate antimicrobial activity of protein extracts from HaCaT cell line against bacterial strains, isolated from clinical materials, obtained from patients with clinical symptoms of acne (Propionibacterium acnes) and gas gangrene (Clostridium perfringens and Sterptococcus pyogenes). Reference strain of Staphylococcus aureus ATCC 25923 also was used. Protein extracts from cultured HaCaT cells were obtained by 3-fold freezing/defreezing cells in dry ice following by centrifugation and incubated with appropriate bacterial suspension (0.5 McFarland scale) during 6 and 24 hours. We observed time-depending and strain-depending activity of HaCaT--protein extract. Interestingly, high activity was demonstrated against strains of S. pyogenes and C. perfringens. Because of increasing bacterial resistance to antibiotics further studies in the field of antimicrobial peptides are required.

Uteriner Gasbrand mit Clostridium Perfringens Sepsis nach intrapartaler gedeckter Uterusruptur

Anaerobic infections with Clostridium perfringens (CP) occur rarely but are associated with considerable maternal mortality. We report the case of a patient who developed uterine gas gangrene postpartum and discuss the management of this infection. A 28-year-old patient, GII, PII with history of Caesarean in 2002, delivered a healthy girl per vacuum extraction. Postpartally she presented with an acute abdomen and a laparotomy was performed. The uterotomy suture was intact but a parametrane tear had to be resutured. 36 hours later the patient's condition worsened quickly. Cellulitis was diagnosed and after receiving the results of the wound swabs (CP positive) from the uterus and haematoma, tazobactam and clindamycin were administered. Her condition continued to deteriorate and gaseous gangrene was seen with unilateral extension to the abdomen reaching as far as the axilla cranially and to the thigh caudally. Due to the extensive infection it was necessary to perform a hysterectomy, necrosis removal and splitting of the fascia followed by several debridements and leaving the wound open in order to avoid anaerobic conditions. The patient was discharged after 21 days. She developed a post-traumatic syndrome with severe depression. Clostridium perfringens is ubiquitous and is found vaginally in ca. 1 - 10 % of healthy women and usually does not cause a serious infection. Under the right conditions it can cause an endometritis leading to sepsis. Early recognition and interdisciplinary treatment are of extreme importance. In this case the surgical treatment through hysterectomy combined with targeted antibiotic therapy, ultimately saved the patient's life.

[Spontaneous gas gangrene in a diabetic patient with Clostridium septicum]

Atraumatic infections due to Clostridium septicum are known to be associated with immunosuppression or even malignancy. In this case report, we present a patient with severe Clostridium septicum infection related to advanced colon cancer that had not previously been diagnosed. The case demonstrates the strong association between Clostridium septicum infections and malignancy, particularly in the presence of other predisposing diseases such as diabetes mellitus. It strongly suggests excluding malignant neoplasms, especially of the gastrointestinal tract, when severe Clostridium septicum infections occur. Moreover, if patients with known colorectal or other malignancy develop septicaemia or spontaneous gas gangrene, clinicians should be aware of Clostridium septicum as one of the main causative agents, as early diagnosis and aggressive treatment are important to improve prognosis.

Fulminant massive gas gangrene caused by Clostridium perfringens

Clostridium perfringens (C.P) gas gangrene is one of the most fulminant infectious diseases. We encountered fulminant massive gas gangrene in a 56- year-old man with alcoholic liver cirrhosis. The patient died 14 hours after diagnosis of gas gangrene (54 hours after admission). Dramatic changes in abdominal CT imaging revealed development of a massive volume of gas in the intra-portal vein, retroperitoneum and abdominal subcutaneous tissue within 24 hours. We also proved C.P infection by immunohistological staining, leading to a diagnosis of C.P gas gangrene.