Characteristics and outcomes of Fusobacterium nucleatum bacteremia--a 6-year experience at a tertiary care hospital in northern Taiwan

Risk of mortality in Fusobacterium species bloodstream infection from a large Australian cohort

BACKGROUND

Fusobacterium species are anaerobic Gram-negative bacilli which are uncommon causes of bloodstream infection (BSI). This genus commonly colonises the gastrointestinal tract and can result in significant morbidity.

METHODS

All blood cultures with growth of Fusobacterium species among residents of Queensland, Australia (population ≈ 5 million) were retrospectively identified over a 20-year period. Clinical, microbiological and outcome information was obtained from state-wide databases.

RESULTS

377 incident Fusobacterium species BSI among 375 individuals for an age and sex-standardised incidence of 4.4 per million residents per year. Median age was 47 years (IQR, 24.9-65.8) and 156 (42%) incident episodes were in females. There was a bimodal frequency distribution with respect to age with peaks occurring around 20 and 65 years, respectively. The most identified source of infection was the abdominal (17%), followed by head and neck (12%). 8% of patients had a septic thrombus present, and 4% had an abscess associated with their BSI. Most isolates were F. nucleatum (142, 38%) and F. necrophorum (140, 37%). 9% of isolates were resistant to penicillin. Older age (aHR 1.02, 95% CI 1.01-1.05), healthcare-associated hospital onset (aHR 3.16, 95% CI 1.35-7.40), and Charlson Comorbidity index (aHR 1.20, 95% CI 1.06-1.35) were all associated with 30-day all cause case-fatality. Oropharyngeal source appeared to be a protective factor (P = 0.02).

CONCLUSIONS

Fusobacterium species BSI results in significant morbidity and can cause death in vulnerable patient groups such as the elderly and those with malignancy. An identifiable oropharyngeal source identifies a favourable host.

The ways Fusobacterium nucleatum translocate to breast tissue and contribute to breast cancer development

Breast cancer is among the most prevalent malignancies in women worldwide. Epidemiological findings suggested that periodontal diseases may be associated with breast cancer, among which Fusobacterium nucleatum is considered an important cross-participant. In this work, we comprehensively summarize the known mechanisms of how F. nucleatum translocates to, colonizes in mammary tumors, and promotes the carcinogenesis. Specifically, F. nucleatum translocates to mammary tissue through the mammary-intestinal axis, direct nipple contact, and hematogenous transmission. Subsequently, F. nucleatum takes advantage of fusobacterium autotransporter protein 2 to colonize breast cancer and uses virulence factors fusobacterium adhesin A and lipopolysaccharide to promote proliferation. Moreover, the upregulated matrix metalloproteinase-9 induced by F. nucleatum does not only trigger the inflammatory response but also facilitates the tumor-promoting microenvironment. Aside from the pro-inflammatory effect, F. nucleatum may also be engaged in tumor immune evasion, which is achieved through the action of virulence factors on immune checkpoint receptors highly expressed on T cells, natural killer cells, and tumor-infiltrating lymphocytes. Taking breast cancer as an example, more relevant research studies may expand our current knowledge of how oral microbes affect systemic health. Hopefully, exploring these mechanisms in depth could provide new strategies for safer and more effective biologic and targeted therapies targeted at breast cancer.

Epidemiology and Clinical Outcomes of Fusobacterium Infections: A Six-Year Retrospective Study

Background and Objectives: Anaerobic bacteria like Fusobacterium can lead to severe and life-threatening infections. The inherent complexities in the isolation of these bacteria may result in diagnostic and therapeutic delays, thereby escalating both morbidity and mortality rates. We aimed to examine data from patients with infections due to Fusobacterium to gain insights into the epidemiology and clinical outcomes of patients with these infections. Methods and Results: We conducted a retrospective analysis of clinical data from a cohort of patients with cultures positive for Fusobacterium species at a tertiary care medical center in the United States. Between 2009 and 2015, we identified 96 patients with cultures positive for Fusobacterium. Patients could be categorized into three groups based on the site of primary infection. Patients with head and neck infections constituted 37% (n 36). Patients with infections of other soft tissue sites accounted for 38.5% (n 37). Patients with anaerobic bacteremia due to Fusobacterium formed 24% (n 23) of the cohort. Surgical intervention coupled with antibiotic therapy emerged as cornerstones of management for patients with head and neck or other soft tissue infections, who generally exhibited more favorable outcomes. Patients with bacteremia were older, more likely to have malignancy, and had a high mortality rate. When speciation was available, Fusobacterium necrophorum was the most frequently isolated species. Conclusions: Our retrospective analysis of epidemiology and clinical outcomes of Fusobacterium infections revealed three distinct cohorts. Patients with head, neck, or soft tissue infections had better outcomes than those with bacteremia. Our findings highlight the importance of employing management strategies based on infection site and underlying comorbidities in patients with Fusobacterium infections. Further research is needed to investigate the optimal therapeutic strategies and identify prognostic indicators to improve clinical outcomes for these complex infections.

Unraveling a Unique Encounter of Fusobacterium nucleatum With Empyema: A Case Report and Review of Literature

We report a case of Fusobacterium nucleatum (F. nucleatum) empyema in a 34-year-old male with no significant past medical history or obvious risk factors who presented with shortness of breath and chest pain. His imaging showed complicated parapneumonic effusion which grew F. nucleatum. He was started on piperacillin-tazobactam. The patient's clinical condition deteriorated despite initial therapeutic efforts, leading to escalated antibiotic therapy and further investigations. The patient's subsequent clinical course included pigtail catheter placement with drainage of fluid requiring tpa and dornase alpha, leading to significant improvement and eventual discharge on oral amoxicillin-clavulanic acid.

No evidence for a common blood microbiome based on a population study of 9,770 healthy humans

Human blood is conventionally considered sterile but recent studies suggest the presence of a blood microbiome in healthy individuals. Here we characterized the DNA signatures of microbes in the blood of 9,770 healthy individuals using sequencing data from multiple cohorts. After filtering for contaminants, we identified 117 microbial species in blood, some of which had DNA signatures of microbial replication. They were primarily commensals associated with the gut (n = 40), mouth (n = 32) and genitourinary tract (n = 18), and were distinct from pathogens detected in hospital blood cultures. No species were detected in 84% of individuals, while the remainder only had a median of one species. Less than 5% of individuals shared the same species, no co-occurrence patterns between different species were observed and no associations between host phenotypes and microbes were found. Overall, these results do not support the hypothesis of a consistent core microbiome endogenous to human blood. Rather, our findings support the transient and sporadic translocation of commensal microbes from other body sites into the bloodstream.

Increasing Fusobacterium infections with Fusobacterium varium, an emerging pathogen

Infections caused by Fusobacterium species are rare; however serious infections with complications or mortality may occur occasionally. We conducted a retrospective study to investigate the clinical features of patients with Fusobacterium infections and the differences between infections caused by the species F. necrophorum, F. nucleatum, and F. varium. Additionally, we attempted to identify risk factors for Fusobacterium-associated mortality. This study included all patients at a large tertiary care teaching hospital in South Korea with Fusobacterium infections from January 2006 to April 2021. Demographic, clinical, laboratory, and outcome data were analyzed. Multiple logistic regression analysis was performed to assess the risk factors for in-hospital mortality associated with F. nucleatum and F. varium infections. We identified 272 patients with Fusobacterium infections during the study period. The number of Fusobacterium cases has increased recently, with F. varium infections markedly increasing since 2016 and causing a significant proportion of infections. Patients with F. varium infections were older and had a higher proportion of nosocomial infections than the other groups. The F. nucleatum and F. varium groups showed higher in-hospital mortality than the F. necrophorum group. Through logistic regression analysis, APACHE II score and serum albumin level were considered risk factors for in-hospital mortality. APACHE II score was positively correlated with age, red cell distribution width, and serum blood urea nitrogen, and negatively correlated with serum albumin level. Infections caused by Fusobacterium species are increasing. F. varium causes a significant proportion of severe infections.

Clinical Differences in Patients Infected with Fusobacterium and Antimicrobial Susceptibility of Fusobacterium Isolates Recovered at a Tertiary-Care Hospital in Korea

Background

Fusobacterium species are obligately anaerobic, gram-negative bacilli. Especially, F. nucleatum and F. necrophorum are highly relevant human pathogens. We investigated clinical differences in patients infected with Fusobacterium spp. and determined the antimicrobial susceptibility of Fusobacterium isolates.

Methods

We collected clinical data of 86 patients from whom Fusobacterium spp. were isolated from clinical specimens at a tertiary-care hospital in Korea between 2003 and 2020. In total, 76 non-duplicated Fusobacterium isolates were selected for antimicrobial susceptibility testing by the agar dilution method, according to the Clinical and Laboratory Standards Institute guidelines (M11-A9).

Results

F. nucleatum was most frequently isolated from blood cultures and was associated with hematologic malignancy, whereas F. necrophorum was mostly prevalent in head and neck infections. Anti-anaerobic agents were more commonly used to treat F. nucleatum and F. varium infections than to treat F. necrophorum infections. We observed no significant difference in mortality between patients infected with these species. All F. nucleatum and F. necrophorum isolates were susceptible to the antimicrobial agents tested. F. varium was resistant to clindamycin (48%) and moxifloxacin (24%), and F. mortiferum was resistant to penicillin G (22%) and ceftriaxone (67%). β-Lactamase activity was not detected.

Conclusions

Despite the clinical differences among patients with clinically important Fusobacterium infections, there was no significant difference in the mortality rates. Some Fusobacterium spp. were resistant to penicillin G, ceftriaxone, clindamycin, or moxifloxacin. This study may provide clinically relevant data for implementing empirical treatment against Fusobacterium infections.

Fusobacterium nucleatum Pleural Empyema in a Patient with Progressive Rheumatoid Arthritis and Immunosuppression

Fusobacterium nucleatum is an anaerobic oral commensal organism that is often associated with inflammatory bowel disease, adverse pregnancy outcomes, respiratory tract infections, and Lemierre's syndrome. Rheumatoid arthritis is often associated with pleuropulmonary manifestations including noninfectious pleural effusions and interstitial lung disease. We present a case of a 47-year-old man with progressive rheumatoid arthritis on immunosuppressive therapy who was found to have a left-sided pleural effusion, thought secondary to possible pneumonia, and was treated with levofloxacin and methylprednisolone. He presented a month later and was found to have a large left-sided thick-walled fluid collection found to be an empyema. A chest tube was placed, and fluid culture grew Fusobacterium nucleatum. The patient was successfully treated with intrapleural fibrinolytic therapy and amoxicillin-clavulanic acid.

Oral Pathogen Fusobacterium nucleatum Coaggregates With Pseudomonas aeruginosa to Modulate the Inflammatory Cytotoxicity of Pulmonary Epithelial Cells

Chronic obstructive pulmonary disease (COPD) is the third leading cause of mortality worldwide, and inflammatory damage induced by bacterial infections is an important contributor to the etiology of COPD. Fusobacterium nucleatum, a recognized periodontal pathogen, is considered as a biomarker of lung function deterioration of COPD patients coinfected with Pseudomonas aerugionsa, but the underlying mechanism is still unclear. This study established single- and dual-species infection models, bacterial simultaneous and sequential infection models, and found that F. nucleatum could coaggregate with P. aeruginosa to synergistically invade into pulmonary epithelial cells and transiently resist P. aeruginosa-induced cytotoxic damage to amplify IL-6 and TNF-α associated inflammation in pulmonary epithelial cells simultaneously infected with P. aeruginosa and F. nucleatum. Furthermore, F. nucleatum pretreatment or subsequential infection could maintain or even aggravate P. aeruginosa-induced inflammatory cytotoxicity of pulmonary epithelial cells. These results indicate that oral pathogen F. nucleatum coaggregates with P. aeruginosa to facilitate bacterial invasion and modulates the inflammatory cytotoxicity of pulmonary epithelial cells, which may contribute to lung function deterioration of COPD patients accompanied with P. aeruginosa and F. nucleatum coinfection.

Identification and Management of Fusobacterium Nucleatum Liver Abscess and Bacteremia in a Young Healthy Man

A 21-year-old previously healthy young man was admitted with five days of fever, persistent cough, worsening shortness of breath, and vomiting. On presentation, laboratory evaluation revealed extremely elevated procalcitonin and leukopenia followed by leukocytosis. The patient was started on empiric antibiotics. Further diagnostic evaluation after initiation of antibiotics included a computed tomography scan, which revealed a large hepatic abscess. Blood cultures obtained on admission grew Fusobacterium nucleatum; fluid obtained from the hepatic abscess also grew F. nucleatum. The patient’s antibiotic regimen was narrowed for specific coverage of F. nucleatum. The liver abscess was drained several times via image-guided percutaneous abscess drainage, with eventual resolution of the abscess. Patient received a prolonged course of intravenous antibiotics and, once stabilized, was discharged on two weeks of Augmentin. Here, we present a rare case of hepatic abscess and bacteremia due to F. nucleatum in a previously healthy young man with good oral hygiene. With this case, we aim to demonstrate the following: (1) the acute onset and rapid disease progression of F. nucleatum bacteremia and liver abscess; (2) how extreme procalcitonin elevation may serve to be a clinically useful early marker of F. nucleatum infection; and (3) the importance of early diagnosis, treatment, and definitive abscess drainage of F. nucleatum bacteremia and liver abscess.

Fusobacterium Nucleatum Empyema: An Atypical Presentation

A 40-year-old man presented to the emergency room and was evaluated in the internal medicine department for unexplained weight loss, asthenia, anorexia and night sweats over the previous 2 months. After a loculated pleural effusion was identified on thoracic computed tomography, purulent fluid was drained from the lung and Fusobacterium nucleatum was isolated. The patient was successfully treated for 27 days with amoxicillin-clavulanic acid. This was an atypical presentation of a common micro-organism implicated in lung infections.

Comparison of 16S Ribosomal RNA Targeted Sequencing and Culture for Bacterial Identification in Normally Sterile Body Fluid Samples: Report of a 10-Year Clinical Laboratory Review

As 16S ribosomal RNA (rRNA)-targeted sequencing can detect DNA from non-viable bacteria, it can be used to identify pathogens from clinical samples even in patients pretreated with antibiotics. We compared the results of 16S rRNA-targeted sequencing and culture for identifying bacterial species in normally sterile body fluid (NSBF): cerebrospinal, pericardial, peritoneal and pleural fluids. Over a 10-year period, a total of 312 NSBF samples were evaluated simultaneously using 16S rRNA-targeted sequencing and culture. Results were concordant in 287/312 (92.0%) samples, including 277 (88.8%) negative and 10 (3.2%) positive samples. Of the 16 sequencing-positive, culture-negative samples, eight showed clinically relevant isolates that included Fusobacterium nucleatum subsp. nucleatum, Streptococcus pneumoniae, and Staphylococcus spp. All these samples were obtained from the patients pretreated with antibiotics. The diagnostic yield of 16S rRNA-targeted sequencing combined with culture was 11.2%, while that of culture alone was 6.1%. 16S rRNA-targeted sequencing in conjunction with culture could be useful for identifying bacteria in NSBF samples, especially when patients have been pretreated with antibiotics and when anaerobic infection is suspected.

Chronic Inflammation as a Link between Periodontitis and Carcinogenesis

Periodontitis is characterized by a chronic inflammation produced in response to a disease-associated multispecies bacterial community in the subgingival region. Although the inflammatory processes occur locally in the oral cavity, several studies have determined that inflammatory mediators produced during periodontitis, as well as subgingival species and bacterial components, can disseminate from the oral cavity, contributing therefore, to various extraoral diseases like cancer. Interestingly, carcinogenesis associated with periodontal species has been observed in both the oral cavity and in extra oral sites. In this review, several studies were summarized showing a strong association between orodigestive cancers and poor oral health, presence of periodontitis-associated bacteria, tooth loss, and clinical signs of periodontitis. Proinflammatory pathways were also summarized. Such pathways are activated either by mono- or polymicrobial infections, resulting in an increase in the expression of proinflammatory molecules such as IL-6, IL-8, IL-1β, and TNF-α. In addition, it has been shown that several periodontitis-associated species induce the expression of genes related to cell proliferation, cell cycle, apoptosis, transport, and immune and inflammatory responses. Intriguingly, many of these pathways are linked to carcinogenesis. Among them, the activation of Toll-like receptors (TLRs) and antiapoptotic pathways (such as the PI3K/Akt, JAK/STAT, and MAPK pathways), the reduction of proapoptotic protein expression, the increase in cell migration and invasion, and the enhancement in metastasis are addressed. Considering that periodontitis is a polymicrobial disease, it is likely that mixed species promote carcinogenesis both in the oral cavity and in extra oral tissues and probably—as observed in periodontitis—synergistic and/or antagonistic interactions occur between microbes in the community. To date, a good amount of studies has allowed us to understand how monospecies infections activate pathways involved in tumorigenesis; however, more studies are needed to determine the combined effect of oral species in carcinogenesis.

Clinical Features and Outcomes of Fusobacterium Species Infections in a Ten-Year Follow-up

Objective

Although uncommon, Fusobacterium infections have a wide clinical spectrum, ranging from local pharyngeal infections to septic shock. Our aim was to characterize and analyze the clinical features and outcomes in patients with Fusobacterium infections, and determine which variables were able to predict a poor outcome.

Methods

We conducted a retrospective, hospital-based study using the computerized records of a second-level Spanish general hospital, serving a population of 155,000 inhabitants. The cohort was enrolled among patients cared for at the hospital between 2007 and 2016. Demographic, clinical data, microbiological characterization and outcomes at discharge, were analyzed.

Results

We collected data for all 26 patients over a 10-year period (annual incidence of 1.78 per 100,000), with an incidence of bacteremia of 0.53 cases per 100,000 population per year. F. nucleatum and F. necrophorum were the most frequent isolations (53.8% and 38.5%, respectively). F. necrophorum was found to be associated with a younger population. Although we found no deaths attributable to Fusobacterium, 15 patients (57%) were found to have severe infections due to this pathogen, and 7 patients (26.9%) were admitted to the Intensive Care Unit (ICU). The only identifiable risk factor for a severe infection (sepsis, septic shock or ICU admission) was the presence of bacteremia.

Conclusions

Fusobacterium infections are uncommon. F. necrophorum tends to cause infection in younger individuals, while F. nucleatum has a preference for older patients. The clinical spectrum is wide, ranging from local, nonsevere infections, such as sinusitis or pharyngitis, to abscess formation and life-threatening infections.

Case series of patients with Fusobacterium nucleatum bacteremia with emphasis on the presence of cancer

Fusobacterium nucleatum is anaerobic oral microbiota that might be associated with cancer. We reported 22 consecutive cases of patients (mean age of 63.8 years (range 34-89), 59.1% male) with F. nucleatum bacteremia that were admitted to a university hospital over a 10-year period. In 17 (77.2%) of these patients, F. nucleatum was the sole possible pathogen. Seven of the 22 patients (31.8%) had active cancer: esophagus carcinoma (n = 3), hematologic malignancies (n = 1), gastrointestinal stromal tumor (n = 1), melanoma (n = 1), and breast cancer (n = 1). In six out of seven patients (85.7%), the F. nucleatum was found within six months of the diagnosis of cancer. Four of seven (57.1%), patients with cancer were on chemotherapy. Three of 22 patients (13.4%) died within 1 month of F. nucleatum bacteremia due to cancer. In conclusion, F. nucleatum bacteremia occurs rarely and when it is found, it is often in patients with cancer, especially those with a recent diagnosis.

Fusobacterium nucleatum infections: clinical spectrum and bacteriological features of 78 cases

PURPOSE

Few series describe the clinical spectrum of Fusobacterium spp. infections. Among them, fewer discuss F. nucleatum, even though there are many clinical cases.

METHODS

We performed a retrospective study over 8 years (from 2007 to 2014) in Limoges University Hospital, France, to assess clinical and bacteriological aspects of infections due to F. nucleatum.

RESULTS

Eighty-one patients with F. nucleatum positive cultures were included in this study, irrespective of sample origin. Abscesses (n = 43), bacteraemia (n = 18) and bone infections (n = 8) were the most common types of infections, Abscesses were found in various organs (mostly skin, brain, pleura, liver). Co-morbidities were found in 38 patients (47 %) with neoplasia, diabetes, and alcoholism and history of smoking. There were more neoplasms in patients with bacteraemia than in patients with abscesses (p = 0.007). In 51 cases (65.4 %), infection was polymicrobial, either during bacteraemia or abscesses. Main associations were with Streptococcus spp., Peptostreptococcus spp. and/or Prevotella spp. The sources of infection, when found, were either dental or gastrointestinal. All isolates were susceptible to penicillin, clindamycin and metronidazole.

CONCLUSIONS

Infections involving F. nucleatum are uncommon and potentially severe, with many abscesses requiring surgery. Bacteraemia was mainly associated with co-morbidities such as cancer. Polymicrobial infections were very common and there is probably interaction and/or synergy between F. nucleatum and some other commensal bacteria to cause infections and abscesses.

Fusobacterium necrophorum and other Fusobacterium spp. isolated from head and neck infections: A 10-year epidemiology study in an academic hospital

BACKGROUND

Fusobacterium spp. from clinical specimens are increasingly reported. We sought to describe the epidemiology, the microbiological, and the clinical characteristics of head and neck infections caused by Fusobacterium necrophorum and other Fusobacterium spp.

MATERIALS AND METHODS

Retrospective cohort study between October 1st, 2004 and September 30(th), 2014 performed in an academic hospital. Electronic patient charts and the laboratory information system were reviewed for demographic and microbiological data. The number and percentages of specific diagnosis and treatment among patients with positive Fusobacterium spp. culture were calculated. The incidence was calculated based on the number of specimens investigated each year.

RESULTS

Included were 230 cultures of 230 patients (median age of 28 years, 61.7% men). F. necrophorum was often found in young patients with high C-reactive protein (CRP) and high number of leukocytes in blood. Other Fusobacterium spp. were often found in middle aged patients with relatively high CRP and slightly increased leukocytes. Three major causes of the isolation of F. necrophorum and other Fusobacterium spp. were acute tonsillitis (n = 18, incidence of 0.2%), peritonsillar abscess (n = 39, 0.5%) and acute otitis (n = 45, 0.1%). While F. necrophorum was found in majority (37/57) of patients with acute tonsillitis or peritonsillar abscess, Fusobacterium spp. other than F. necrophorum were found in the majority (35/45) of patients with acute otitis. Isolated fusobacteria were susceptible to beta-lactam antibiotics, clindamycin and metronidazole. The outcomes of patients with Fusobacterium spp. were good.

CONCLUSION

F. necrophorum and other Fusobacterium spp. are rare cause of head and neck infections. The infections are well treated by combination of antibiotics and surgery.

Pyogenic liver abscess caused by Fusobacterium in a 21-year-old immunocompetent male

A 21-year-old male with no significant past medical history, presented with right upper quadrant (RUQ) abdominal pain along with fevers and chills. Lab work revealed leukocytosis, anemia, and slightly elevated alkaline phosphatase. Viral serology for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus were negative and he was immunocompetent. Computed tomography imaging revealed hepatic abscesses, the largest measuring 9.5 cm. Empiric antibiotics were started and percutaneous drains were placed in the abscesses. Anaerobic cultures from the abscesses grew Fusobacterium nucleatum. This is a gram negative anaerobic bacteria; a normal flora of the oral cavity. Fusobacterium is most commonly seen in Lemiere’s disease, which is translocation of oral bacteria to the internal jugular vein causing a thrombophlebitis and subsequent spread of abscesses. Our patient did not have Lemiere’s, and is the first case described of fusobacterium pyogenic liver abscess in a young immunocompetent male with good oral hygiene. This case was complicated by sepsis, empyema, and subsequent abscesses located outside the liver. These abscesses’ have the propensity to flare abruptly and can be fatal. This case not only illustrates fusobacterium as a rare entity for pyogenic liver abscess, but also the need for urgent diagnosis and treatment. It is incumbent on physicians to diagnose and drain any suspicious hepatic lesions. While uncommon, such infections may develop without any overt source and can progress rapidly. Prompt drainage with antibiotic therapy remains the cornerstone of therapy.

Myocardial infection due to Fusobacterium nucleatum

Fusobacterium nucleatum is an anaerobic gram-negative bacillus, which inhabits the oropharynx, gastrointestinal tract, and female genital tract. Infections classically affect the head and neck. We report a patient with a myocardial mass due to F. nucleatum, initially thought to be a neoplasm, and discuss anaerobic cardiac infections.

Incidence, risk factors, and outcomes of Fusobacterium species bacteremia

Background

The aim of this study was to assess the epidemiology of intestinal parasitoses during a 5-year period in patients attending a tertiary-care hospital in a non-endemic setting.

Methods

In the period 2006–2010, 15,752 samples from 8,886 patients with clinically suspected parasitosis were subjected to macroscopic and microscopic examination, to parasitic antigen detection assays, and to cultures for protozoa and nematodes. Real-time PCR assays for the differentiation of Entamoeba histolytica and E. dispar and for the detection of Dientamoeba fragilis were also used.

A statistical analysis evaluating the demographic data of the patients with intestinal parasitic infections was performed.

Results

Intestinal parasitic infections were diagnosed in 1,477 patients (16.6% prevalence), mainly adults and immigrants from endemic areas for faecal-oral infections; protozoa were detected in 93.4% and helminths in 6.6% of the cases, the latter especially in immigrants. Blastocystis hominis was the most common intestinal protozoan, and G. intestinalis was the most frequently detected among pathogenic protozoa, prevalent in immigrants, males, and pediatric patients. Both single (77.9%) and mixed (22.1%) parasitic infections were observed, the latter prevalent in immigrants.

Conclusions

Despite the importance of the knowledge about the epidemiology of intestinal parasitoses in order to adopt appropriate control measures and adequate patient care all over the world, data regarding industrialized countries are rarely reported in the literature. The data presented in this study indicate that intestinal parasitic infections are frequently diagnosed in our laboratory and could make a contribution to stimulate the attention by physicians working in non-endemic areas on the importance of suspecting intestinal parasitoses.

Incidence, risk factors, and outcomes of Fusobacterium species bacteremia

Background

Fusobacterium species (spp.) bacteremia is uncommon and has been associated with a variety of clinical presentations. We conducted a retrospective, population based study to determine the relative proportion of species in this genus causing bacteremia and the risk factors for infection and adverse clinical outcomes.

Methods

All cases of Fusobacterium spp. bacteremia detected at a regional microbiology laboratory serving outpatient and acute care for a population of approximately 1.3 million people over 11 years were identified from a computerized database. Clinical data on these cases was extracted from an administrative database and analyzed to determine underlying risk factors for and outcomes of infection.

Results

There were 72 incident cases of Fusobacterium spp. bacteremia over the study period (0.55 cases/100,000 population per annum). F. nucleatum was the most frequent species (61%), followed by F. necrophorum (25%). F. necrophorum bacteremia occurred in a younger population without underlying comorbidities and was not associated with mortality. F. nucleatum bacteremia was found in an older population and was associated with underlying malignancy or receiving dialysis. Death occurred in approximately 10% of F. nucleatum cases but causality was not established in this study.

Conclusions

Fusobacterium spp. bacteremia in our community is uncommon and occurs in approximately 5.5 cases per million population per annum. F. necrophorum occurred in an otherwise young healthy population and was not associated with any mortality. F. nucleatum was found primarily in older patients with chronic medical conditions and was associated with a mortality of approximately 10%. Bacteremias from other Fusobacterium spp. were rare.

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.

Fusobacterium nucleatum infection mimicking metastatic cancer

A 48-year-old man presented with fevers, chills, weight loss, multiple liver masses, and several superficial and deep venous thromboses in lower extremities. Cancer work up was negative. A liver biopsy grew Fusobacterium nucleatum. To our knowledge, F. nucleatum infection presenting with multiple liver masses and Trousseau-like syndrome has not been reported earlier.

Epidemiology and clinical outcomes of patients with Fusobacterium bacteraemia

This 10-year retrospective study assessed the epidemiology and outcomes of patients with Fusobacterium bacteraemia (FB) at a tertiary-care hospital in the USA - this is the second study focusing on FB in adults to be conducted in the USA in 30 years. Demographic, clinical, laboratory, treatment, and outcome data were collected and statistically analysed. Nineteen patients with FB were identified, representing 0·11% of bacteraemia cases. Mean age was 58·6 years with equal gender distribution. Common comorbidities included cardiovascular disease (CVD) and immunosuppression. Thirty-day mortality was 21·1%, and 68·4% of FB patients required intensive care unit (ICU) admission. Elevated creatinine levels and mental status changes were associated with higher mortality (P = 0·0181 and 0·0374, respectively). CVD, diabetes, and ICU admission were associated with increased length of hospital stay (P = 0·0017, 0·0010, and 0·0379, respectively). The prevalence of FB at our hospital was very low, with poor outcomes associated with increased creatinine level, mental status changes, CVD, diabetes and ICU admission.