Isolation of Clostridium in human infections: evaluation of 114 cases

Clostridium paraputrificum Bacteremia in a Patient with Rectal Cancer after Receiving Antibiotic Therapy for Acute Pharyngolaryngitis

Clostridium paraputrificum bacteremia is very rare, and its clinical importance is poorly understood. An 86-year-old man was receiving lascufloxacin therapy for acute pharyngolaryngitis before presenting to our emergency department with a recurrent fever. Two sets of blood cultures on admission revealed C. paraputrificum. A stool culture showed a reduced presence of intestinal commensal bacteria. After admission, the patient's fever resolved without antibiotics. Colonoscopy revealed a rectal tumor. Rectal tumor and microbial substitutions caused by antibiotics may have led to bacteremia. When treating C. paraputrificum bacteremia, physicians should be mindful of coexisting gastrointestinal disorders and a history of antibiotic administration.

Clostridium perfringens Empyema: Anaerobic Invasion in an Uncommon Location

Clostridium perfringens bacteremia arises due to skin inoculation from the external environment or translocation from the gastrointestinal tract. In the event of bacteremia, it tends to colonize in anaerobic environments due to its obligatory anaerobic nature. Its inoculation in the lung, albeit rare, can occur if an anaerobic nidus is created. In the presented case, the patient developed C. perfringens bacteremia andempyema in the area of lung necrosis caused by acute pulmonary embolism. He did not have any history of chest trauma, and the source of bacteremia was deemed to be via gut translocation. The patient was noted to have multiple gastric ulcers on endoscopy and jejunal wall thickening, which likely led to the bacterial translocation into the bloodstream. He underwent video-assisted thoracoscopic surgery-assisted decortication and intravenous antibiotics, eventually leading to clinical improvement. To identify the source of Clostridium in the absence of penetrating trauma, a thorough gastrointestinal evaluation, including a colonoscopy, is warranted to identify the pathology leading to the gastrointestinal translocation.

Bacteremia due to Clostridium innocuum: Analysis of four cases and literature review

Clostridium innocuum is a Gram-positive anaerobic spore-forming bacillus that has been identified as part of the normal intestinal microbiota. This bacterium has been rarely associated with human infections, and only few severe infections have been reported until now. In this work, we report on four patients with bacteremia due to C. innocuum, which were well identified by MALDI-TOF MS. Moreover, a review of the previous published cases of bacteremia due to this anaerobic bacterium has been performed.

Clinical significance and outcomes of Clostridium tertium bacteremia: analysis of 62 cases in neutropenic and non-neutropenic patients

The clinical significance of Clostridium tertium bacteremia is still uncertain. We evaluated the incidence, clinical characteristics, and outcomes of C. tertium bacteremia and identified differences between neutropenia and non-neutropenia. All adult patients with C. tertium bacteremia in a 2700-bed tertiary center between January 2004 and November 2021 were retrospectively enrolled. The first episode of C. tertium bacteremia in each patient was included in the analysis. Among 601 patients with Clostridium species bacteremia, 62 (10%) had C. tertium bacteremia, and of these 62 patients, 39 (63%) had had recent chemotherapy, and 31 (50%) had neutropenia or hematologic malignancy. C. tertium bacteremia originated frequently from a gastrointestinal tract infection such as enterocolitis (34%), primary bacteremia (29%), and secondary peritonitis (18%), and 34% of patients had polymicrobial bacteremia. Hematologic malignancy, prior antibiotic treatment, neutropenic enterocolitis, and primary bacteremia were significantly associated with C. tertium bacteremia in neutropenic patients, whereas solid tumor, hepatobiliary disease, secondary peritonitis, polymicrobial bacteremia, and a higher frequency of eradicable infection foci were significantly associated with C. tertium bacteremia in non-neutropenic patients. There was 15% 30-day mortality. APACHE II score (adjusted odds ratio [aOR], 1.5; 95% confidence interval [CI], 1.1-2.1) and secondary peritonitis (aOR, 25.9; 95% CI, 3.0-224.7) were independent risk factors for 30-day mortality. The prevalence of C. tertium bacteremia is low, and the characteristics of C. tertium bacteremia are significantly different between neutropenic and non-neutropenic patients. Appropriate investigation for gastrointestinal mucosal injury should be performed to improve treatment outcomes in this form of bacteremia.

Clostridium subterminale infection in a patient with diffuse large B-cell lymphoma and haemophagocytic syndrome: A case report and literature review

Although uncommon, infection caused by Clostridium subterminale may be life threatening particularly in immunocompromised patients. We report here a rare presentation of a patient with diffuse large B-cell lymphoma and haemophagocytic syndrome associated with C. subterminale bacteraemia. The management of the patient is described as well as a review of medical literature. Infection by Clostridium species, including C. subterminale, should be considered in a febrile patient with a haematologic malignancy. The case highlights the importance of using gene sequencing for identification of this anaerobic organism.

Epidemiology, aetiology and clinical characteristics of clostridial bacteraemia: a 6-year population-based observational study of 386 patients

The objective of this study is to provide a population-based clinical, epidemiological and microbiological overview of clostridial bacteraemia. All cases of bacteraemia in the Skåne Region between 2014 and 2019 with a species currently belonging to the Clostridium genus were identified in the regional clinical microbiology database. Clinical data were retrieved by medical chart-review. A total of 386 unique episodes of clostridial bacteraemia were found resulting in an incidence rate of 4.9/100.000 person-years. The median age was 76 with 56% males. The incidence rate ratio was 34.3 for those aged 80 + vs 0–59. The minimum inhibitory concentrations varied between species but were universally low for metronidazole and carbapenems. Malignancy was the most common co-morbidity, in 47% of patients and most pronounced for C. septicum. Criteria for sepsis and septic shock were met in 69% and 17%, respectively. The 28-day mortality was 26%. High age, absence of fever, high C-reactive protein and high SOFA-score were all significantly associated with mortality. We present the highest incidence rate of clostridial bacteraemia to date. Clostridial bacteraemia is a severe condition with acute onset, affecting elderly with co-morbidities, most pronounced malignancies. Mortality is related to acute manifestations rather than to background factors.

Fatal non-traumatic gas gangrene caused by Clostridium perfringens type A in a Siberian Husky dog

An 8-y-old, castrated male Siberian Husky dog was admitted to an emergency clinic with acute collapse and severe swelling of both forelimbs, ventral thorax, and axillary region. The clinical assessment, with laboratory tests and radiologic investigation, confirmed severe subcutaneous emphysema and multi-organ failure. The animal died while receiving emergency treatment. On postmortem examination, Clostridium perfringens was isolated from the subcutaneous fluid and the effusion from the thoracic and abdominal cavities. Relevant histopathology findings included subcutaneous emphysema and multi-organ perivascular and intravascular, intralesional myriad 0.5-3-µm gram-positive rod bacteria, with no associated inflammation. Whole-genome sequencing and phylogenetic analysis identified C. perfringens type A. Virulence genes detected included cpa (alpha toxin), cadA (v-toxin), colA (collagenase A), nagH (hyaluronidase), nanH, nanI, nanJ (sialidases), and pfoa (perfringolysin). These virulence genes have previously been reported to act synergistically with alpha toxin in C. perfringens-mediated gas gangrene.

Clostridium innocuum: Microbiological and clinical characteristics of a potential emerging pathogen

Clostridium innocuum is an anaerobic, gram-positive, spore-forming bacterium identified by Smith and King in 1962 after being isolated from a patient with an appendiceal abscess. Its name, C. innocuum, reflected its clinically "innocuous" nature based on observed lack of virulence in animal models of infection. Since that time, C. innocuum has been identified as both part of the normal intestinal flora and the cause of a rare, intrinsically vancomycin-resistant opportunistic infection in immunocompromised patients. More recently, reports from Taiwan suggest that C. innocuum, in addition to being a known extraintestinal pathogen, may also be a diarrheal pathogen that causes a C. difficile infection-like antibiotic-associated diarrheal illness. However, unanswered questions about the clinical relevance of C. innocuum remain. Here we review the microbiological and clinical characteristics of this emerging pathogen.

A Middle-Aged Woman With Hematochezia, Hypotension, and Leg Cramps

CASE PRESENTATION

A 57-year-old woman with a history of mantle cell lymphoma presented to the ED with complaints of vomiting, bleeding per rectum, and leg cramps, that started 6 h prior to her arrival. She had received chemotherapy a week prior. Her leg cramps were not associated with pain or swelling of the legs; she also denied any trauma to the legs. She did complain of mild lower abdominal pain at presentation. Review of systems was negative for fever, chills, diarrhea, chest pain, and dizziness. She denied using alcohol or nonsteroidal anti-inflammatory drugs. The patient was tachycardic with a systolic BP (SBP) of 85 mm Hg and was administered 1-L normal saline, with improvement in her SBP to 90 mm Hg. The hematocrit level was 24%, the WBC count was 0.3 × 10⁹/L, and the platelet count was 6 × 10⁹/L in the ED. On arrival in the ICU, she was noted to have an SBP of 70 mm Hg. Resuscitation with IV fluids was initiated, followed by transfusion of packed RBCs and platelets, based on the blood counts. Despite aggressive fluid resuscitation and improvement in her hemoglobin, the patient remained persistently hypotensive. The diagnosis of underlying septic shock because of neutropenia was considered; the patient was started on vasopressors and empirical broad-spectrum antibiotics, with improvement in her BP. After this, the patient was sent to radiology for a CT scan of the abdomen and pelvis with contrast to evaluate for mesenteric infarction, enteric or colonic bleeding, and the need for arterial embolization.

Clostridium ramosum rapidly identified by MALDI-TOF MS. A rare gram-variable agent of bacteraemia

Clostridium ramosum is an enteric anaerobic, endospore-forming, gram-positive rod with a low GC content that is rarely associated with disease in humans. We present a case of C. ramosum bacteraemia. To the best of our knowledge, this is the second case of C. ramosum bacteraemia in an elderly patient presenting with fever, abdominal pain and bilious emesis. We highlight the Gram stain variability, the lack of visualization of spores and the atypical morphology of the colonies that showed C. ramosum in a polymicrobial presentation that initially appeared to show monomicrobial bacteraemia. The microorganism was rapidly identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). We present a comprehensive literature review of 32 cases of clinical infections by C. ramosum in which we describe, if available, sex, age, clinical symptoms, predisposing conditions, other organisms present in the blood culture, other samples with C. ramosum , identification methodology, treatment and outcome.

Clinical relevance of Clostridium bacteremia: An 8-year retrospective study

Clostridium spp. are recovered from 25% of the blood culture positive with anaerobes. However, the clinical relevance of Clostridium bacteremia has been controverted in the literature, particularly for C. perfringens. We aimed to evaluate the clinical relevance of Clostridium bacteremia, either due to C. perfringens or other Clostridium species, and to identify the risk factors of mortality in these patients. A retrospective cohort study was conducted from January 2010 to April 2018. All the patients with at least one blood culture positive with any Clostridium species were included. Eighty-one patients with a least one blood culture positive with any Clostridium species were included. Seventy patients (86.4%) fulfilled the criteria for clinically relevant bacteremia. Bacteremia due to C. perfringens tended to be less clinically relevant than other Clostridium species but this was not statistically significant (76% vs 91.2%, P = 0.09). In case of clinically relevant bacteremia, the 30-day mortality rate was 31.4%. In multivariate analysis, adequate empiric antimicrobial therapy was significantly associated with survival (P = 0.03). In conclusion, bacteremia due to C. perfringens or other Clostridium species is usually clinically relevant. This finding was also supported by an improved survival at 30 days when adequate empiric antimicrobial therapy was administered.

Clinical features of Clostridium bacteremia in cancer patients: A case series review

Clostridium bacteremia is a well-known cause of infection in patients with gastrointestinal lesions. However, the clinical characteristics of this infection in cancer patients are unclear. We retrospectively reviewed cases of blood cultures positive for Clostridium species between March 1, 2004 and May 30, 2018 at the Shizuoka Cancer Center Hospital. Medical records of 40 patients who met the study criteria were reviewed for age, gender, underlying disease, history of disease, blood culture results, laboratory test results, and radiographic data. The common sources of Clostridium species in these patients were hepatobiliary tract infection and liver abscess (13/40; 32.5%) and bacteremia/enteritis due to gastrointestinal tumor (13/40; 32.5%). All patients had malignancies, with the most common being colorectal cancer (n = 9) followed by pancreatic cancer (n = 8) and gastric cancer (n = 6). The most common species isolated was C. perfringens followed by C. ramnosum. Twenty-five patients (62.5%) had polymicrobial bacteremia with the following organisms isolated from concurrent blood cultures: Escherichia coli (n = 8) and Klebsiella spp. (n = 7). Of these bacteremia cases, 37 had digestive organ lesions such as gastrointestinal malignancy, peritoneal dissemination, or intestinal infiltration. Seventeen patients died, resulting in an overall mortality rate of 42.5% at 30 days. Common cases of Clostridium bacteremia were derived from gastrointestinal lesions, and because Clostridium bacteremia is observed regardless of species, it should be considered necessary to examine gastrointestinal lesions.

Clostridium sporogenes bacteremia in an immunocompetent patient

Of the 200 Clostridium spp. known to exist, approximately 30 have been associated with human disease. Commonly found in soil, marine sediment and mammalian intestinal tracts, these gram-positive bacilli are known to cause infections ranging from cellulitis to septicemia. Isolates that are identified by clinical microbiology laboratories include Clostridium perfrigens species in 20–40% of cases. However, when Clostridium sporogenes is identified, is rarely considered to be pathogenic. We present a case of Clostridium sporogenes bacteremia secondary to lower limb cellulitis and osteomyelitis in an immunocompetent patient.

Wound botulism caused by Clostridium subterminale after a heroin injection

Botulism is caused by toxin production from many species of Clostridium, most commonly Clostridium botulinum as well as C. baratii and C. butyricum. Development of wound botulism is associated with injection drug users but has also been described in traumatic injuries with exposure to soil. A patient presented to the emergency department with a complaint of descending, progressive weakness. He recently reported skin popping with heroin injections. Heptavalent botulinum antitoxin was obtained from the [Center for Disease Control and Prevention (CDC)]. On hospital day seven, the anaerobic wound cultures resulted with growth of Clostridium subterminale.

Effects of nutrient loading on sediment bacterial and pathogen communities within seagrass meadows

Eutrophication can play a significant role in seagrass decline and habitat loss. Microorganisms in seagrass sediments are essential to many important ecosystem processes, including nutrient cycling and seagrass ecosystem health. However, current knowledge of the bacterial communities, both beneficial and detrimental, within seagrass meadows in response to nutrient loading is limited. We studied the response of sediment bacterial and pathogen communities to nutrient enrichment on a tropical seagrass meadow in Xincun Bay, South China Sea. The bacterial taxonomic groups across all sites were dominated by the Gammaproteobacteria and Firmicutes. Sites nearest to the nutrient source and with the highest NH₄⁺ and PO₄³⁻ content had approximately double the relative abundance of putative denitrifiers Vibrionales, Alteromonadales, and Pseudomonadales. Additionally, the relative abundance of potential pathogen groups, especially Vibrio spp. and Pseudoalteromonas spp., was approximately 2‐fold greater at the sites with the highest nutrient loads compared to sites further from the source. These results suggest that proximity to sources of nutrient pollution increases the occurrence of potential bacterial pathogens that could affect fishes, invertebrates and humans. This study shows that nutrient enrichment does elicit shifts in bacterial community diversity and likely their function in local biogeochemical cycling and as a potential source of infectious diseases within seagrass meadows.

An unusual odontogenic infection due to Clostridium subterminale in an immunocompetent patient: A case report and review of the literature

Clostridium subterminale is an anaerobic spore-forming bacterium usually associated with infections in patients who are immunocompromised. This case report focuses on a rare presentation of a multifascial space odontogenic infection associated with the bacterial isolate Clostridium subterminale. The management of an odontogenic infection associated with an isolate of Clostridium subterminale in an immunocompetent female is described, as well as a review of the literature.

Clostridium innocuum is a vancomycin-resistant pathogen that may cause antibiotic-associated diarrhoea

OBJECTIVES

Clostridium innocuum can cause extraintestinal infection in patients with underlying diseases. The role of C. innocuum in antibiotic-associated diarrhoea (AAD) remains unknown.

METHODS

Clinical information of 103 patients from whom C. innocuum was isolated was reviewed. We carried out cellular and animal experiments to examine the pathogenic potential of C. innocuum in AAD.

RESULTS

Eighty-eight per cent (91/103) of the 103 patients received antibiotics within 2 weeks of diarrhoea onset. Patients were further classified into two groups, severe colitis and diarrhoea, according to clinical severity level. The mortality rate was 13.6% (14/103) among the patients from whom C. innocuum was isolated. The lowest concentrations at which 90% of the isolates were inhibited for metronidazole and vancomycin were 0.5 and 16 mg/L, respectively. All isolates tested were susceptible to metronidazole but resistant to vancomycin. Nineteen randomly selected isolates (ten from severe colitis group, nine from diarrhoea group) were subjected to further in vitro cellular examinations. The level of cytotoxicity to Vero cells was significantly higher in isolates from the severe colitis group at both 24 and 48 hours after inoculation (24 and 48 hours, p 0.042 and 0.033, respectively). We observed apoptotic changes that subsequently led to cell death in C. innocuum-infected Vero cells. Tissue damages, necrotic changes and oedema were observed in the mouse ileal loop infected by C. innocuum.

CONCLUSIONS

Vancomycin-resistant C. innocuum may play a potential role as a causative agent of AAD. The clinical manifestations of AAD caused by C. innocuum were diarrhoea or severe colitis, including pseudomembranous colitis.

Botulism-like symptoms in an immunocompetent patient with Clostridium subterminale bacteremia

Clostridium subterminale is a low virulence species of Clostridium that is an infrequent cause of human infections. We report a case of C. subterminale bacteremia in an immunocompetent patient who developed botulism-like symptoms.

Anaerobic Bacteria in Clinical Specimens - Frequent, But a Neglected Lot: A Five Year Experience at a Tertiary Care Hospital

INTRODUCTION

Anaerobic bacteria which constitute a significant proportion of the normal microbiota also cause variety of infections involving various anatomic sites. Considering the tedious culture techniques with longer turnaround time, anaerobic cultures are usually neglected by clinicians and microbiologists.

AIM

To study the frequency of isolation of different anaerobic bacteria from various clinical specimens.

MATERIALS AND METHODS

A retrospective study to analyse the frequency of isolation of different anaerobic bacteria, was conducted over a period of five years from 2011 to 2015 including various clinical specimens submitted to anaerobic division of Microbiology laboratory. Anaerobic bacteria were isolated and identified following standard bacteriological techniques.

RESULTS

Pathogenic anaerobes (n=336) were isolated from 278 (12.48%) of overall 2227 specimens processed with an average yield of 1.2 isolates. Anaerobes were isolated as polymicrobial flora with or without aerobic bacterial pathogens in 159 (57.2%) patients. Anaerobic Gram-negative bacilli (140, 41.7%) were the predominant isolates. B. fragilis group (67, 19.9%) were the most commonly isolated anaerobic pathogens. Anaerobes were predominantly isolated from deep seated abscess (23.9%).

CONCLUSION

Pathogenic anaerobes were isolated from various infection sites. Unless culture and susceptibility tests are performed as a routine, true magnitude of antimicrobial resistance among anaerobic pathogens will not be known. Knowledge of the distribution of these organisms may assist in the selection of appropriate empirical therapy for anaerobic infections.

Spontaneous C. septicum gas gangrene: A literature review

As the infectious disease paradigm undergoes a subtle shift, unusual infections associated with malignancy and immunosuppression are being increasingly reported. Spontaneous or non-traumatic Clostridium septicum infection is one such unusual infection which has gained prominence. This article aims to understand the pathophysiology, clinical manifestations and current trends in diagnosing and treating this rare but deadly infection. To understand the multifactorial causation of this infection a review of published cases of spontaneous C. septicum gas gangrene was performed and a total of 94 such cases were identified. Several factors were analyzed for each case: age, infection location and underlying illness, presenting signs and symptoms, neutropenia, gross pathology of the colon, antibiotic use, surgical intervention, and survival. A known or occult malignancy was present in 71% patients and an overall mortality of 67% was observed.

Clostridium difficile bacteremia: Report of two cases in French hospitals and comprehensive review of the literature

We report two cases of bacteremia due to Clostridium difficile from two French hospitals. The first patient with previously diagnosed rectal carcinoma underwent courses of chemotherapy, and antimicrobial treatment, and survived the C. difficile bacteremia. The second patient with colon perforation and newly diagnosed lung cancer underwent antimicrobial treatment in an ICU but died shortly after the episode of C. difficile bacteremia. A review of the literature allowed the identification of 137 cases of bacteremia between July 1962 and November 2016. Advanced age, gastro-intestinal disruption, severe underlying diseases and antimicrobial exposure were the major risk factors for C. difficile bacteremia. Antimicrobial therapy was primarily based on metronidazole and/or vancomycin. The crude mortality rate was 35% (21/60).

Clostridium subterminale septicemia in an immunocompetent patient

Clostridium subterminale is a Clostridium species that has been rarely isolated in the blood of immunocompromised patients. We report a case of C. subterminale septicemia in an immunocompetent patient who presented with acute mediastinitis following spontaneous esophageal rupture.

Clostridium difficile infection: Early history, diagnosis and molecular strain typing methods

Recognised as the leading cause of nosocomial antibiotic-associated diarrhoea, the incidence of Clostridium difficile infection (CDI) remains high despite efforts to improve prevention and reduce the spread of the bacterium in healthcare settings. In the last decade, many studies have focused on the epidemiology and rapid diagnosis of CDI. In addition, different typing methods have been developed for epidemiological studies. This review explores the history of C. difficile and the current scope of the infection. The variety of available laboratory tests for CDI diagnosis and strain typing methods are also examined.

Severe Sepsis due to Clostridium perfringens Bacteremia of Urinary Origin: A Case Report and Systematic Review

Clostridium perfringens bacteremia is an uncommon yet serious clinical syndrome that typically arises from a gastrointestinal source. However, clinicians should consider nongastrointestinal sources as well. We present a rare case of C. perfringens bacteremia of urinary origin that required surgical intervention for definitive treatment. A 61-year-old male presented with acute nausea and vomiting, altered mental status, and chronic diarrhea. His physical exam revealed right costovertebral tenderness and his laboratory work-up revealed acute renal failure. Percutaneous blood cultures grew C. perfringens. Cross-sectional imaging revealed a right-sided ureteral stone with hydronephrosis, which required nephrostomy placement. On placement of the nephrostomy tube, purulent drainage was identified and Gram stain of the drainage revealed Gram-variable rods. A urinary source of C. perfringens was clinically supported. Although it is not a common presentation, nongastrointestinal sources such as a urinary source should be considered in C. perfringens bacteremia because failure to recognize a nongastrointestinal source can delay appropriate treatment, which may include surgical intervention.

Genome sequence of Clostridium sporogenes DSM 795(T), an amino acid-degrading, nontoxic surrogate of neurotoxin-producing Clostridium botulinum

Clostridium sporogenes DSM 795 is the type strain of the species Clostridium sporogenes, first described by Metchnikoff in 1908. It is a Gram-positive, rod-shaped, anaerobic bacterium isolated from human faeces and belongs to the proteolytic branch of clostridia. C. sporogenes attracts special interest because of its potential use in a bacterial therapy for certain cancer types.

Genome sequencing and annotation revealed several gene clusters coding for proteins involved in anaerobic degradation of amino acids, such as glycine and betaine via Stickland reaction. Genome comparison showed that C. sporogenes is closely related to C. botulinum. The genome of C. sporogenes DSM 795 consists of a circular chromosome of 4.1 Mb with an overall GC content of 27.81 mol% harboring 3,744 protein-coding genes, and 80 RNAs.

Empyema caused by Clostridium bifermentans: A case report

Previously considered to be nonpathogenic, Clostridium bifermentans has been implicated in a wide variety of infections over the past three decades, ranging from septic arthritis to endocarditis. The authors of this article describe a case involving a 60-year-old man who was found to have an empyema caused by C bifermentans. The authors review similar cases and discuss the course of treatment for this infection.

A case of pneumonia with associated empyema caused by Clostridium bifermentans is described. C bifermentans is an anaerobic, spore-forming, Gram-positive bacillus. This organism is infrequently reported as a cause of infection in humans, and older publications tended to regard it as nonpathogenic. However, in more recent reports, C bifermentans has been documented as a cause of septic arthritis, osteomyelitis, soft tissue infection, abdominal infections, brain abscess, bacteremia and endocarditis. The present case is the third reported case of empyema caused by C bifermentans, and it serves to further define the spectrum of illness due to this uncommon organism.

Gut microbiome compositional and functional differences between tumor and non-tumor adjacent tissues from cohorts from the US and Spain

Colorectal cancer (CRC) is the third most common cancer in the world and the second leading cause of cancer deaths in the US and Spain. The molecular mechanisms involved in the etiology of CRC are not yet elucidated due in part to the complexity of the human gut microbiota. In this study, we compared the microbiome composition of 90 tumor and matching adjacent tissue (adjacent) from cohorts from the US and Spain by 16S rRNA amplicon sequencing in order to determine the impact of the geographic origin on the CRC microbiome. Data showed a significantly (P < 0.05) higher Phylogenetic Diversity (PD) for the US (PD Adjacent = 26.3 ± 5.3, PD Tumor = 23.3 ± 6.2) compared to the Spanish cohort (PD Adjacent = 18.9 ± 5.9, PD Tumor = 18.7 ± 6.6) while no significant differences in bacterial diversity were observed between tumor and adjacent tissues for individuals from the same country. Adjacent tissues from the Spanish cohort were enriched in Firmicutes (SP = 43.9% and US = 22.2%, P = 0.0001) and Actinobacteria (SP = 1.6% and US = 0.5%, P = 0.0018) compared to US adjacent tissues, while adjacent tissues from the US had significantly higher abundances of Fusobacteria (US = 8.1% and SP = 1.5%, P = 0.0023) and Sinergistetes (US = 0.3% and SP = 0.1%, P = 0.0097). Comparisons between tumor and adjacent tissues in each cohort identified the genus Eikenella significantly over represented in US tumors (T = 0.024% and A = 0%, P = 0.03), and the genera Fusobacterium (T = 10.4% and A = 1.5%, P = <0.0001), Bulleida (T = 0.36% and A = 0.09%, P = 0.02), Gemella (T = 1.46% and A = 0.19%, P = 0.03), Parvimonas (T = 3.14% and A = 0.86%, P = 0.03), Campylobacter (T = 0.15% and A = 0.008%, P = 0.047), and Streptococcus (T = 2.84% and A = 2.19%, P = 0.05) significantly over represented in Spanish tumors. Predicted metagenome functional content from 16S rRNA surveys showed that bacterial motility proteins and proteins involved in flagellar assembly were over represented in adjacent tissues of both cohorts, while pathways involved in fatty acid biosynthesis, the MAPK signaling pathway, and bacterial toxins were over represented in tumors. Our study suggests that microbiome compositional and functional dissimilarities by geographic location should be taken in consideration when approaching CRC therapeutic options.

Clostridium subterminale septicemia in a patient with esophageal cancer

Clostridium subterminale (C. subterminale) is a pathogenic species of Clostridium that has been infrequently isolated. We report a case of C. subterminale bacteremia causing sepsis in a patient with metastatic gastrointestinal malignancy.

Infections associated with solid malignancies

Although solid tumors comprise the vast majority of cancers, the incidence of serious infectious complications in this population is much less than in patients with hematologic malignancies. Most infections involving patients with solid tumors comprise two groups. First, patients acquire infections as a result of the cancer itself, due to either mass effect that interrupts normal function or destruction of the normal barriers to infection. Second, patients acquire infections as a complication of the treatments they receive, such as chemotherapy, radiation, surgery, or medical devices. Advances in the management of cancer have resulted in a gradual stepwise improvement in survival for patients with most types of solid tumors. Much of this improvement has been attributed to advances in cancer screening, diagnosis, and therapeutic modalities. In addition, improvements in the prevention, diagnosis, and treatment of infections have likely contributed to this prolonged survival. This review highlights select articles in the medical literature that shed light on the epidemiology and pathophysiology of infections in patients with solid tumors. In addition, this review focuses upon the diagnosis and treatment of these infections and their recent advances.

Clinical significance and outcomes of Clostridium perfringens bacteremia--a 10-year experience at a tertiary care hospital

BACKGROUND

The mortality rate of patients with Clostridium perfringens bacteremia is 27-44%. Typically, the clinical characteristics of this infection are non-specific, which leads to considerable difficulty with the diagnosis and early initiation of appropriate therapy.

METHODS

A retrospective cohort study of patients who were hospitalized between August 2002 and July 2011 with C. perfringens bacteremia was conducted within a 3715-bed teaching hospital in northern Taiwan. The patients identified in this search were included when they had fever or other clinical features suggestive of systemic infection. Multiple logistic regression analysis was applied to determine the independent risk factors of 30-day mortality.

RESULTS

A total of 93 patients were identified. Elderly patients with comorbid illnesses, especially renal insufficiency or malignancy, were at risk of developing C. perfringens bacteremia, and 23 patients (24.7%) had nosocomial bacteremia. The 30-day and attributed mortalities were 26.9% (25/93) and 8.6% (8/93), respectively. Nosocomial infection was a significant predictor for mortality within 30 days (odds ratio 19.378, 95% confidence interval 2.12-176.99; p=0.009), independent of other disease parameters. Other independent risk factors included the Charlson weighted index of comorbidity, length of hospitalization, and stay in the intensive care unit.

CONCLUSIONS

Early recognition of this critical infection and early initiation of appropriate antibiotic treatment by surgical intervention or drainage is essential.

Spore-forming Bacilli and Clostridia in human disease

Many Gram-positive spore-forming bacteria in the Firmicute phylum are important members of the human commensal microbiota, which, in rare cases, cause opportunistic infections. Other spore-formers, however, have evolved to become dedicated pathogens that can cause a striking variety of diseases. Despite variations in disease presentation, the etiologic agent is often the spore, with bacterially produced toxins playing a central role in the pathophysiology of infection. This review will focus on the specific diseases caused by spores of the Clostridia and Bacilli.

Clostridium innocuum Bacteremia in a patient with acquired immunodeficiency syndrome

Clostridium innocuum is an unusual cause of infections in humans. This report describes the first published case of C. innocuum bacteremia in a patient with AIDS and provides a review of the literature. The case suggests that recent C. difficile infection may be a risk factor for the subsequent development of C. innocuum bacteremia among immunosuppressed persons. Because of their intrinsic resistance to several common antibiotics, including vancomycin, C. innocuum infections are important to recognize.

Pneumorachis caused by metastatic gas gangrene

Pneumorachis has previously been described only after spread from a contiguous site or after a traumatic event. Our patient experienced sepsis due to multiple enteric organisms, and gas was identified within the spinal canal on computed tomographic imaging. We present the 1st case of pneumorachis caused by disseminated infection.

Epidemiology of Clostridium species bacteremia in Calgary, Canada, 2000-2006

OBJECTIVES

To define the incidence, risk factors for acquisition, and outcomes associated with clostridial bacteremia in a large Canadian health region.

METHODS

Retrospective population-based surveillance for clostridial bacteremia was conducted among all residents of the Calgary Health Region (population 1.2 million) during 2000-2006.

RESULTS

One hundred and thirty-eight residents had incident Clostridium species bacteremia (1.8 per 100,000/year); 45 (33%) were nosocomial, 55 (40%) were healthcare-associated community onset, and 38 (28%) were community acquired. Older age and a number of underlying conditions were risk factors for acquiring Clostridium species bacteremia most importantly hemodialysis [relative risk (RR) 212.3; 95% confidence interval (CI) 106.5-385.5], malignancy (RR 40.2; 95% CI 27.6-58.1), and Crohn's disease (RR 11.2; 95% CI 3.0-29.4). Clostridium perfringens was most commonly identified with 58 (42%) isolates followed by Clostridium septicum (19; 14%), Clostridium ramosum (13; 9%), Clostridium clostridiiforme (8; 6%), and Clostridium difficile (7; 5%). Reduced susceptibility to penicillin occurred in 14/135 (10%), to metronidazole in 2/135 (1%), and to clindamycin in 36/135 (27%) isolates. The median length of stay was 12.7 days and 39/130 (30%) patients died in hospital for mortality rate of 0.5 per 100,000/year.

CONCLUSIONS

Clostridium species bacteremia is associated with a significant burden of illness and hemodialysis and cancer patients are at highest risk.

Phenotyping Clostridium septicum infection: a surgeon's infectious disease

BACKGROUND

Clostridium septicum infection is associated with malignancy. Whether disease phenotype is affected by malignant status is not known. Surgical treatment is used frequently but its impact on survival has not been examined in a cohort >30 patients.

METHODS

A PubMed search of English language journal articles yielded 320 cases. Full information (infection location, cancer type, operative intervention, and survival) was available for 224 cases + 7 at our institution not previously reported.

RESULTS

Seventy-two percent of patients had malignancy or malady of the gastrointestinal (GI) or hematologic (HEME) organ systems. HEME survival was inferior to GI survival (35% versus 55%, P = 0.03). Overall, patients who underwent operation had improved survival (57% versus 26%; P < 0.0001) and this association was maintained within GI and HEME cohorts (P = 0.002 and 0.005, respectively). More GI than HEME patients underwent operation (81% versus 51%, P < 0.001). GI patients were more likely than HEME patients to experience infection of skin and soft tissues (SSTI, P = 0.006). Diabetics were more likely to experience SSTI than nondiabetics (77% versus 45%, P < 0.001).

CONCLUSIONS

C. septicum infectious phenotype varies with host milieu. The SSTI phenotype is more common in GI and diabetic patients. This recognition may aid in directing the search for occult malignancy, which must be performed given the >70% incidence of concomitant cancer. This infection is more fatal in HEME versus GI patients, perhaps due in part to less HEME group operative intervention. Primary surgical therapy should be considered in GI or HEME patients as operative intervention benefits both groups.

Outcome of brain abscess by Clostridium perfringens

OBJECTIVE

Despite the aggressive infection of soft tissue caused by Clostridium perfringens (gas gangrene-necrotizing fasciitis), a brain abscess with this bacteria treated by early surgical excision, debridement of necrotic tissue, and antibiotic coverage may be expected to have a good recovery. Long-term follow-up has not been well established in this group of patients. We report this case to show the outcome at 3 years post surgical and antibiotic treatment for C. perfringens brain abscess and stress the need for urgent intervention to achieve good outcome. We also present a literature review of Clostridial brain abscesses since the 1960s.

CLINICAL PRESENTATION

A 53-year-old man was brought to the emergency room after having a witnessed seizure status postassault 3 days before admission. On presentation, he was febrile, disoriented, lethargic, and demonstrated right upper extremity weakness. A computed tomographic scan of the head showed a left frontoparietal depressed cranial fracture complicated with gas and intraparenchymal air fluid level cavity.

INTERVENTION

Emergent surgery for debridement and excision of necrotic tissue was performed. Empiric intravenous antibiotic therapy was started and penicillin G was added for 6 weeks after C. perfringens was demonstrated.

CONCLUSION

Despite the severe infection and effect of C. perfringens in soft tissues in the brain, it appears that emergent surgical debridement and antibiotic coverage will yield an excellent outcome for these patients.

Subcutaneous abscess caused by Clostridium perfringens and osteomyelitis in a dog

A case of a subcutaneous abscess caused by Clostridium perfringens infection in a five-month-old dog is reported in this study. Clinical examination, radiological findings and cytological analysis of abscess fluid were consistent with Clostridium induced disease. Treatment including drainage of the abscess and antibiotic therapy led to rapid clinical improvement. However, despite aggressive medical therapy and proper wound care, the deep soft tissue infection led to osteomyelitis with premature closure of the growth plates of the tibia and secondary bone shortening. Prolonged treatment with metronidazole and amoxicillin-clavulanic acid resulted in an excellent outcome with normal weight bearing.

Typing of Clostridium perfringens strains by use of Random Amplified Polymorphic DNA (RAPD) system in comparison with zymotyping

The definition of strain clonality postulates that strains showed identical phenotypic and genetic traits are likely to descend from a common ancestor even if they were isolated from different sources and locations. Regarding this definition, non-epidemiologically linked strains might be clonal strains. To overcome this ambiguity, the discriminatory capability of RAPD typing was assessed firstly on eight Clostridium perfringens strains proven to be chromosomally different with one being the mutant of another one. Thirteen primers were tested but only two were able to differentiate seven of the eight strains. With none of the used primers it was possible to differentiate the parental strain and its mutant harboring an insertion of 180 kb. The four most discriminant primers were retained to determine the RAPD fingerprints of a further 20 previously zymotyped strains from which seventeen were unrelated. To compare the two typing systems, the zymotype of the eight chromosomally different strains was determined. Thus, the discriminatory index was calculated on the basis of 25 unrelated C. perfringens strains. This was 0.97 with RAPD typing and 0.99 with zymotyping. From these results we conclude that the RAPD typing which is less fastidious than zymotyping can be used as an epidemiological marker for C. perfringens.

The possible significance of Clostridium spp. in blood cultures

The significance of Clostridium spp. in blood cultures was evaluated by two methods. In the first part of the study, a group of 80 patients with Clostridium spp. bacteraemia was compared with a group of 100 patients with Bacillus spp. in blood cultures, making the assumption that Bacillus almost invariably represents contamination (pseudobacteraemia). Significant differences were found between the two groups, suggesting that growth of Clostridium did not represent pseudobacteraemia. Patients with Clostridium bacteraemia were older, had a higher frequency of gastrointestinal disease (especially colorectal tumours), were associated more frequently with polymicrobial bacteraemia, and had a higher mortality rate. In the second part of the study, each of the 80 cases of Clostridium bacteraemia was evaluated individually for clinical relevance by an infectious diseases expert. In two-thirds of the cases, isolates of Clostridium from blood were considered to be of clinical relevance, whereas in one-third of cases, the clinical significance of this finding was doubtful. It was concluded that growth of Clostridium spp. in blood cultures, even in the absence of one of the histotoxic syndromes, is often of clinical significance, and that such findings should be properly evaluated and not ignored.