Antimicrobial susceptibilities of Campylobacter fetus: report from a reference laboratory

Campylobacter fetus is known to cause human disease, particularly in elderly and immunocompromised hosts. There are limited published data for antimicrobial susceptibility patterns with this organism, and no interpretive criteria are available. We reviewed antimicrobial susceptibilities of C. fetus isolates tested at a tertiary care center and reference laboratory over an 11-year period. C. fetus isolates from patients treated at Mayo Clinic and those sent as referrals for identification and susceptibility were included. Antimicrobial susceptibility testing was performed using agar dilution for ciprofloxacin, doxycycline, erythromycin, gentamicin, meropenem, and tetracycline. Geographic distribution, culture source, organism minimal inhibitory concentration (MIC) distributions, and MIC50 and MIC90 were examined. Excluding duplicates, 105 unique isolates were identified from 110 positive cultures. Blood cultures represented the most common source, followed by body fluids, skin and soft tissue, and central nervous system. Gentamicin and meropenem had favorable MIC50 and MIC90 of 1 µg/mL. Ciprofloxacin demonstrated an MIC50 of 1 µg/mL; however, the MIC90 was >2 µg/mL. Erythromycin demonstrated MIC50 and MIC90 of 2 µg/mL. Tetracycline and doxycycline were tested on a limited number of isolates and showed a wide range of MICs. Gentamicin and meropenem demonstrated favorable MICs in C. fetus isolates. These may represent therapeutic options for consideration in serious C. fetus infections, pending susceptibility results. Ciprofloxacin, which showed variable results, may be more appropriate for use only after susceptibility testing. C. fetus interpretive criteria are needed to aid clinicians in selection of both empiric and definitive therapies.

IMPORTANCE

Our findings contribute to the scant literature on Campylobacter fetus antimicrobial susceptibility test results. We used a reference test method of agar dilution and provide MICs for a large number of organisms and antimicrobial agents.

Comparative pangenomic analysis of Campylobacter fetus isolated from Spanish bulls and other mammalian species

Campylobacter fetus comprises two closely related mammal-associated subspecies: Campylobacter fetus subsp. fetus (Cff) and Campylobacter fetus subsp. venerealis (Cfv). The latter causes bovine genital campylobacteriosis, a sexually-transmitted disease endemic in Spain that results in significant economic losses in the cattle industry. Here, 33 C. fetus Spanish isolates were whole-genome sequenced and compared with 62 publicly available C. fetus genomes from other countries. Genome-based taxonomic identification revealed high concordance with in silico PCR, confirming Spanish isolates as Cff (n = 4), Cfv (n = 9) and Cfv biovar intermedius (Cfvi, n = 20). MLST analysis assigned the Spanish isolates to 6 STs, including three novel: ST-76 and ST-77 for Cfv and ST-78 for Cff. Core genome SNP phylogenetic analysis of the 95 genomes identified multiple clusters, revealing associations at subspecies and biovar level between genomes with the same ST and separating the Cfvi genomes from Spain and other countries. A genome-wide association study identified pqqL as a Cfv-specific gene and a potential candidate for more accurate identification methods. Functionality analysis revealed variations in the accessory genome of C. fetus subspecies and biovars that deserve further studies. These results provide valuable information about the regional variants of C. fetus present in Spain and the genetic diversity and predicted functionality of the different subspecies.

Campylobacter coli enteritis associated with Campylobacter fetus bacteremia, spondylodiscitis, and late CIED-related endocarditis, a case report

Campylobacter sp. is widely considered a leading causative agent of bacterial food-borne gastrointestinal illness. Discitis and endocarditis caused by Campylobacter spp. are extremely rare. We describe the case of a 94-year-old man who was admitted for recent lumbar pain, diarrhea, and fever. C. fetus and C. coli were identified by MALDI-TOF from blood and stool samples respectively. MRI of the spine showed L5-S1 discitis. Patient was treated with 6 weeks of amoxicillin with clinical and microbiological response until cardiac implantable electronic device (CIED) related endocarditis occurred four weeks after the end of the antibiotic treatment. He was treated with another 6 weeks amoxicillin regimen, with a favorable outcome after a 6-month follow-up. Enteric infection with Campylobacter spp. in a debilitated patient should raise the possibility of a co-infection with another more invasive species such as C. fetus, leading to systemic invasion. In case of Campylobacter fetus bacteremia, a search for endocarditis and spondylodiscitis is recommended even in the absence of specific clinical signs.

Campylobacter in Africa - A specific viewpoint

Campylobacter infections and campylobacteriosis-associated post-infectious sequelae are a significant global health burden that needs to be addressed from a specific African perspective. We conducted a comprehensive literature search on NCBI PubMed to compile a comprehensive narrative review article on Campylobacter infections in Africa, focusing on key aspects in human and veterinary medicine as well as food hygiene. We specifically focused on the epidemiology of enteropathogenic Campylobacter spp. in sub-Saharan and North Africa considering antimicrobial susceptibility. The most significant sequela resulting from molecular mimicry to Campylobacter surface structures is the Guillain-Barré syndrome, which was mainly examined in the context of limited studies conducted in African populations. A dedicated subsection is allocated to the limited research on the veterinary medically important species Campylobacter fetus. There are significant differences in the composition of the gut microbiome, especially in rural areas, which affect the colonization with Campylobacter spp. and the manifestation of campylobacteriosis. There may be a problem of overdiagnosis due to asymptomatic colonization, particularly in the detection of Campylobacter using molecular biological techniques. To reduce the colonization and infection rate of Campylobacter, we propose implementing several control measures and urge further research to improve the current understanding of the peculiarities of campylobacteriosis in Africa.

Campylobacter fetus seeding of a cavernous malformation resulting in brain abscess: case report and literature review

Microbial seeding of a cerebral cavernous malformation is an extremely rare occurrence with only 3 cases reported in the literature thus far. Campylobacter fetus is an opportunistic pathogen that rarely causes neurological infection with only 3 cases of C. fetus cerebral abscesses and 38 cases of C. fetus meningitis reported in the literature. There have been no cases of cerebral cavernous malformation seeding by C. fetus reported to date. We report the first case of cerebral cavernous malformation seeding by C. fetus, a case occurring in a previously healthy 16-year-old female who presented with suspected left cerebellar cavernous malformation with subacute hemorrhage. She underwent a suboccipital craniectomy for the resection of the cavernous malformation with additional intraoperative findings suggestive of cerebral abscess. Following positive blood and CSF cultures and surgical pathology results, the patient was diagnosed with C. fetus meningoencephalitis with co-infected left cerebellar cavernous malformation. This is the fourth reported case of microbial seeding of a cerebral cavernous malformation, and to our knowledge, the first case of a C. fetus-infected cavernous malformation. Compared to previous reports, the clinical events of this case strongly support the presence of a preexisting lesion that was secondarily seeded versus de novo formation as a result of prior infection.

[Prevalence and geographical distribution of bovine sexually transmitted diseases in the province of Formosa, Argentina]

Bovine genital campylobacteriosis (BGC) and bovine trichomonosis (BT) are sexually transmitted diseases (STDs) that affect bovine breeding herds, decreasing their reproductive efficiency. The objective of this work was to estimate the prevalence of these diseases and their temporal-spatial distribution in the province of Formosa, Argentina. The cross-sectional study conducted between 2018 and 2021 included a total of 15,571 bulls, inter-herd prevalence being 29.62% and 17.23% for BGC and BT, respectively. The prevalence of positive animals was 2.05% for BGC and 0.43% for BT. The temporal-spatial analysis of BGC showed two distinct spatial groupings, one group had a low risk of contracting the disease (RR = 0.13; p < 0.001; 2018-2021) while the other group had a high risk (RR = 2.84; p < 0.001; 2020-2021). BT had a high-risk group for the disease (RR = 35.24; p < 0.001; 2019). This study shows that STDs are endemic in the region, providing updated and valuable information as a tool for the health management of these diseases.

Prosthetic valve endocarditis caused by Campylobacter fetus: a case report and literature review

Campylobacter fetus is a Gram-negative bacillus typically associated with bacteremia in immunocompromised patients. Prosthetic valve endocarditis (PVE) is a serious complication of prosthetic valve surgery, with a high mortality rate if not treated promptly. We present a rare case of PVE caused by C. fetus. A man in his mid-60s presented to the Emergency Department with a fever and showed elevated C-reactive protein concentrations. He had prosthetic mitral and aortic valve replacement surgery 15 years previously. Gram-negative rods were detected in a blood culture. These rods were identified as C. fetus using matrix-assisted laser desorption ionization time-of-flight mass spectrometry and confirmed by 16S rRNA sequencing. The patient was treated with gentamicin and imipenem, and underwent valve replacement surgery. C. fetus was isolated in a left atrial appendage swab obtained during the surgery. Follow-up blood cultures were negative after treatment. However, after a cardiac arrest event, the patient's general condition deteriorated, and he died. To the best of our knowledge, this is the first case of PVE caused by C. fetus in Korea and the second fatality to date. This case highlights the importance of considering C. fetus as a potential cause of PVE, even in patients without known risk factors.

Campylobacter fetus Invasive Infections and Risks for Death, France, 2000-2021

Campylobacter fetus accounts for 1% of Campylobacter spp. infections, but prevalence of bacteremia and risk for death are high. To determine clinical features of C. fetus infections and risks for death, we conducted a retrospective observational study of all adult inpatients with a confirmed C. fetus infection in Nord Franche-Comté Hospital, Trevenans, France, during January 2000-December 2021. Among 991 patients with isolated Campylobacter spp. strains, we identified 39 (4%) with culture-positive C. fetus infections, of which 33 had complete records and underwent further analysis; 21 had documented bacteremia and 12 did not. Secondary localizations were reported for 7 (33%) patients with C. fetus bacteremia, of which 5 exhibited a predilection for vascular infections (including 3 with mycotic aneurysm). Another 7 (33%) patients with C. fetus bacteremia died within 30 days. Significant risk factors associated with death within 30 days were dyspnea, quick sequential organ failure assessment score >2 at admission, and septic shock.

Campylobacter fetus foodborne illness outbreak in the elderly

In June 2021, a cluster of seven cases of Campylobacter fetus infections occurred in a rehabilitation center and caused significant morbidity in elderly patients including five with bacteremia and two with osteoarticular medical device infections. The genetic identity identified by whole genome sequencing of the different Campylobacter fetus strains confirms a common source. This foodborne illness outbreak may have resulted from the consumption of unpasteurized dairy products, such as a cow's raw milk cheese resulting from a farm-to-fork strategy.

Antimicrobial resistance in Campylobacter fetus: emergence and genomic evolution

Campylobacter fetus is a pathogen, which is primarily associated with fertility problems in sheep and cattle. In humans, it can cause severe infections that require antimicrobial treatment. However, knowledge on the development of antimicrobial resistance in C. fetus is limited. Moreover, the lack of epidemiological cut-off values (ECOFFs) and clinical breakpoints for C. fetus hinders consistent reporting about wild-type and non-wild-type susceptibility. The aim of this study was to determine the phenotypic susceptibility pattern of C. fetus and to determine the C. fetus resistome [the collection of all antimicrobial resistance genes (ARGs) and their precursors] to describe the genomic basis of antimicrobial resistance in C. fetus isolates over time. Whole-genome sequences of 295 C. fetus isolates, including isolates that were isolated in the period 1939 till the mid 1940s, before the usage of non-synthetic antimicrobials, were analysed for the presence of resistance markers, and phenotypic antimicrobial susceptibility was obtained for a selection of 47 isolates. C. fetus subspecies fetus (Cff) isolates showed multiple phenotypic antimicrobial resistances compared to C. fetus subspecies venerealis (Cfv) isolates that were only intrinsic resistant to nalidixic acid and trimethoprim. Cff isolates showed elevated minimal inhibitory concentrations for cefotaxime and cefquinome that were observed in isolates from 1943 onwards, and Cff isolates contained gyrA substitutions, which conferred resistance to ciprofloxacin. Resistances to aminoglycosides, tetracycline and phenicols were linked to acquired ARGs on mobile genetic elements. A plasmid-derived tet(O) gene in a bovine Cff isolate in 1999 was the first mobile genetic element observed, followed by detection of mobile elements containing tet(O)-aph(3')-III and tet(44)-ant(6)-Ib genes, and a plasmid from a single human isolate in 2003, carrying aph(3')-III-ant(6)-Ib and a chloramphenicol resistance gene (cat). The presence of ARGs in multiple mobile elements distributed among different Cff lineages highlights the risk for spread and further emergence of AMR in C. fetus. Surveillance for these resistances requires the establishment of ECOFFs for C. fetus.

Campylobacter fetus Bacteremia Related to Vascular Prosthesis and Pseudoaneurysm Infection: A Case Report and Review

BACKGROUND

Campylobacter fetus rarely causes gastrointestinal diseases but shows an affinity for the endovascular epithelium.

METHODS

We describe a case of C. fetus bacteremia related to vascular prosthesis and pseudoaneurysm infection, with a review of the literature.

RESULTS

A 67-year-old male was admitted with a history of fever, weakness and painful swelling of the groin. After unsuccessful treatment with ciprofloxacin, the patient was transferred to our hospital, where he had been previously treated for aortoiliac occlusive disease including a prosthetic aortobifemoral and popliteal bypass with polyester graft placement. An angiography showed a pseudoaneurysm in the groin and, therefore, repair of the pseudoaneurysm, removal of the prosthesis and biologic graft placement were performed. Blood cultures and tissue samples of the vascular prosthesis and pseudoaneurysm yielded C. fetus resistant to ciprofloxacin. The patient was treated with meropenem for four weeks, followed by amoxicillin-clavulanate for another two weeks after discharge. Eight previously published cases of C. fetus bacteremia due to infected cardiovascular prosthetic devices (prosthetic heart valves, implantable cardioverter-defibrillators and a permanent pacemaker) were summarized in the review.

CONCLUSIONS

To our knowledge, this is the first report of a C. fetus bacteremia related to post-surgical infection of a vascular prosthesis causing a pseudoaneurysm.

Genome analysis of clinical isolate of Campylobacter fetus subspecies fetus MMM01 from India reveals genetic determinants of pathogenesis and adaptation

In this study we report the whole genome sequencing (WGS) based analysis of blood-borne Campylobacter fetus subsp. fetus MMM01 isolated from a diabetic patient to obtain deeper insights in to the virulence and host adaptability. The sequenced genome of C. fetus subsp. fetus MMM01 along with reference genomes retrieved from NCBI was subjected to various in-silico analysis including JSpecies, MLST server, PATRIC server, VFanalyzer, CARD, PHASTER to understand their phylogenetic relation, virulence and antimicrobial resistance profile. The genome had a size of 1,788,790 bp, with a GC content of 33.09%, nearly identical to the reference strain C. fetus subsp. fetus 82-40. The MLST based phylogenetic tree constructed revealed the polyphyletic branching and MMM01 (ST25) was found to be closely related to ST11, both belong to the sap-A serotype which are more common in human infections. VFanalyzer identified 88 protein-coding genes coding for several virulence factors including Campylobacter adhesion to fibronectin, flagellar apparatus, cytolethal distending toxin operons and Campylobacter invasion antigen proteins which enhance the virulence of bacteria along with resistance genes against antibiotics including fluoroquinolone, chloramphenicol, tetracycline, and aminoglycoside in MMM01, which points to enhanced survival and pathogenicity of this zoonotic pathogen. It was interesting to find that MMM01 lacked FGI-II island found in most of the clinical isolates, which encoded CRISPR Cas and prophage II regions. More details about the complexity and evolution of this zoonotic pathogen could be learned from future studies that concentrate on comparative genome analysis using larger genome datasets.

Case Report: Campylobacter fetus caused pyogenic spondylodiscitis with a presentation of cauda equina syndrome after instrumented lumbar fusion surgery

Spondylodiscitis with/without neurologic impairment is a serious infection, predominantly occurring in high-risk patients. Campylobacter fetus caused spondylodiscitis is very rare. Evidence-based therapeutic concepts for lumbar spondylodiscitis are lacking. A 64-year-old high-risk woman underwent decompression with instrumented lumbar fusion. Six months after index surgery, she developed pyelonephritis, which deteriorated to sepsis and presentation of cauda equina syndrome. She underwent urgent revision with decompression, debridement, and instrumentation removal, and received long-term antibiotics. Culture grew Campylobacter fetus, previously not reported as a cause of spondylodiscitis after elective instrumented lumbar fusion. Emergent debridement and removal of instrumentation, with 2 months of targeted intravenous antibiotics followed by 6 weeks of oral antibiotics led to complete spondylodiscitis resolution. Prompt diagnostics and targeted antibiotic treatment are paramount when dealing with spinal infections, particularly in patients with rare causative pathogens like Campylobacter fetus. Concomitant neurological complications may require emergent surgical management in the case of cauda equina syndrome.

Investigation of Campylobacter fetus in breeding bulls of private farms in Bangladesh

BACKGROUND

Bovine genital campylobacteriosis (BGC) is a venereal disease caused by Campylobacter fetus that has a negative impact on animal reproduction. The bull is considered to be a symptomless carrier that spreads the disease agent to breeding cows, causing infertility and sporadic abortion.

AIM

The study aims to estimate the prevalence, identify risk factors of Campylobacter fetus (C. fetus) infection and antimicrobial resistance pattern of the C. fetus isolates.

METHOD

A cross-sectional survey was conducted in Mymensingh district of Bangladesh. Bull smegma samples (single sample from each bull) were collected from 300 bulls from four farms and tested via culture, biochemical identification and finally 16S rRNA and cdtA gene-based molecular assays (PCR) for herd and animal-level prevalence estimation. Herd- and animal-level data on risk factors were collected from the farmers using a pretested questionnaire and analysed by univariable and multivariable logistic regression models with a p value of <0.05 was taken statistically significant for both analyses.

RESULTS

Among the surveyed farms, 75% (95% CI: 19.4%-99.4%) were confirmed to have bulls infected with Campylobacter fetus at herd level. However, animal-level occurrence of C. fetus was estimated to be 8.7% (26/300) (95% CI: 5.7%-12.4%). Natural service increases the odds of campylobacteriosis 38.18 times (95% CI: 13.89-104.94) in comparison to artificial insemination for C. fetus infection in bulls. Significantly, half of the isolates (50%, n = 13) were identified to be multidrug resistant (MDR) for three to five antimicrobial agents.

CONCLUSION

This study highlights the need to develop official guidelines for C. fetus control and prevention in Bangladesh including mandatory artificial insemination in reproductive cows and heifers, routine screening of breeding bulls for C. fetus free status.

Campylobacter fetus Meningitis: A diagnosis to suggest in immunocompromised patients

Campylobacter fetus causes in humans mostly gastroenteritis. Systemic infection occurs almost exclusively in immunocompromised patients with chronic debilitating diseases. We report the case of a Campylobacter fetus meningitis in a woman aged 48 years with a history of systemic lupus erythematosus treated with corticosteroids and immunosuppressive drugs. Cerebrospinal fluid culture was positive for Campylobacter fetus. The evolution was favorable using imipenem and ciprofloxacin.

Cervical osteomyelitis potentially caused by Campylobacter fetus

Campylobacter fetus is a rare pathogen in humans. It mainly causes invasive infections in immunosuppressed patients. Herein, we report the first case of cervical vertebral osteomyelitis in a previously healthy man with a history of daily alcohol consumption. Treatment was given for six weeks with excellent clinical recovery and normalization of laboratory markers.

Evaluation of PCR assays for Campylobacter fetus detection and discrimination between C. fetus subspecies in bovine preputial wash samples

Campylobacter fetus is a zoonotic pathogen found in cattle, in which it is one of the main causes of infectious infertility. Most diagnostic laboratories use PCR as quick easy tool for C. fetus identification. However, there is no standardized PCR assay for C. fetus detection and subspecies differentiation, hindering the comparison of results. In this study, we evaluated selected PCR assays targeting the 16S rRNA, gyrB, cpn60, cstA, cdtB and nahE genes for C. fetus identification and ISCfe1, sapB2, parA and virB11 for subspecies differentiation. Analytical sensitivity and specificity were assessed for each PCR assay, and the assays were then tested on 289 bull preputial samples that had also been analysed by 16S rRNA barcode metagenomics. In total, 41 C. fetus-positive samples were included. The P12 PCR assay targeting the gyrB gene performed best, detecting the pathogen in 95.1% of positive samples. For the discrimination of C. fetus subspecies, we were able to identify a proportion (85.4%) of the C. fetus-positive samples correctly as C. fetus venerealis with at least one subspecies-specific PCR, but C. fetus fetus was not detected in any of the samples tested. Remarkably, C. fetus subspecies amplification was observed following PCR on some samples (33.1%) considered C. fetus-negative, highlighting the need for rigorous criteria for discriminating between C. fetus subspecies, to improve understanding of the role of the two C. fetus subspecies in the epidemiology and pathogenesis of bovine infectious infertility.

Campylobacter fetus bacteremia and meningitis in an acute lymphoblastic leukemia patient undergoing maintenance therapy: a case report

BACKGROUND

Campylobacter fetus is an uncommon Campylobacter species, and its infections mainly cause infective endocarditis, aortic aneurysm, and meningitis rather than enteritis. It is more likely to be detected in blood than Campylobacter jejuni or Campylobacter coli, specifically reported in 53% of patients. In our case, C. fetus was detected in both blood and cerebrospinal fluid (CSF) cultures.

CASE PRESENTATION

A 33-year-old woman, who was on maintenance chemotherapy for acute lymphoblastic leukemia (ALL), presented to our clinic with chief complaints of severe headache and nausea. Blood and CSF cultures revealed C. fetus. We administrated meropenem 2 g intravenously (IV) every 8 h for 3 weeks, and she was discharged without neurological sequelae.

CONCLUSION

We encountered a case of C. fetus meningitis without gastrointestinal symptoms, neck stiffness or jolt accentuation in a patient with ALL. Undercooked beef was considered the source of C. fetus infection in this case, suggesting that the need for a neutropenic diet and safe food handling be considered.

Phylogenomic analysis for Campylobacter fetus ocurring in Argentina

Background and Aim:

Campylobacter fetus is one of the most important pathogens that severely affects livestock industry worldwide. C. fetus mediated bovine genital campylobacteriosis infection in cattle has been associated with significant economic losses in livestock production in the Pampas region, the most productive area of Argentina. The present study aimed to establish the genomic relationships between C. fetus strains, isolated from the Pampas region, at local and global levels. The study also explored the utility of multi-locus sequence typing (MLST) as a typing technique for C. fetus.

Materials and Methods:

For pangenome and phylogenetic analysis, whole genome sequences for 34 C. fetus strains, isolated from cattle in Argentina were downloaded from GenBank. A local maximum likelihood (ML) tree was constructed and linked to a Microreact project. In silico analysis based on MLST was used to obtain information regarding sequence type (ST) for each strain. For global phylogenetic analysis, a core genome ML-tree was constructed using genomic dataset for 265 C. fetus strains, isolated from various sources obtained from 20 countries.

Results:

The local core genome phylogenetic tree analysis described the presence of two major clusters (A and B) and one minor cluster (C). The occurrence of 82% of the strains in these three clusters suggested a clonal population structure for C. fetus. The MLST analysis for the local strains revealed that 31 strains were ST4 type and one strain was ST5 type. In addition, a new variant was identified that was assigned a novel ST, ST70. In the present case, ST4 was homogenously distributed across all the regions and clusters. The global analysis showed that most of the local strains clustered in the phylogenetic groups that comprised exclusively of the strains isolated from Argentina. Interestingly, three strains showed a close genetic relationship with bovine strains obtained from Uruguay and Brazil. The ST5 strain grouped in a distant cluster, with strains obtained from different sources from various geographic locations worldwide. Two local strains clustered in a phylogenetic group comprising intercontinental Campylobacter fetus venerealis strains.

Conclusion:

The results of the study suggested active movement of animals, probably due to economic trade between different regions of the country as well as with neighboring countries. MLST results were partially concordant with phylogenetic analysis. Thus, this method did not qualify as a reliable subtyping method to assess C. fetus diversity in Argentina. The present study provided a basic platform to conduct future research on C. fetus, both at local and international levels.

fetus in bovine endometrial cells by qPCR

BACKGROUND

Campylobacter fetus subsp. fetus is the causal agent of sporadic abortion and infertility in bovines that produces economic losses in livestock.

AIMS

This study evaluates the capability of C. fetus subsp. fetus to invade and survive in bovine endometrial epithelial cells and attempts to describe a pathogenic mechanism of this microorganism.

METHODS

Primary culture of bovine endometrial epithelial cells was challenged with C. fetus subsp. fetus. Intracellular bacteria, represented by the number of genomic copies (g.c.) were quantified at 0, 2, 4, 10, and 24 hours post-infection (h.p.i.), by quantitative polymerase chain reaction (qPCR). The presence of intracellular bacteria was evaluated by immunofluorescence and immunohistochemistry.

RESULTS

The results showed that only viable C. fetus subsp. fetus could invade endometrial cells. The g.c. number in assays with viable C. fetus subsp. fetus reached an average value of 656 g.c., remained constant until 4 h.p.i., then decreased to 100 g.c, at 24 h.p.i. In assays with non-viable microorganisms, the average value of g.c. was less than 1 g.c. and never changed. The intracellular presence of this bacteria was confirmed at 2 h.p.i. by immunofluorescence and immunohistochemistry.

CONCLUSION

The results suggest that only C. fetus subsp. fetus viable can invade bovine endometrial epithelial cells but will not replicate in them, indicating that the endometrial cells do not represent a replication niche for this pathogen. Nonetheless, this invasion capability suggests that this type of cell could be employed by the pathogen to spread to other tissues.

Accurate and fast identification of Campylobacter fetus in bulls by real-time PCR targeting a 16S rRNA gene sequence

Campylobacter fetus is an important animal pathogen that causes infectious infertility, embryonic mortality and abortions in cattle and sheep flocks. There are two recognized subspecies related with reproductive disorders in livestock: Campylobacter fetus subsp. fetus (Cff) and Campylobacter fetus subsp. venerealis (Cfv). Rapid and reliable detection of this pathogenic species in bulls is of upmost importance for disease control in dairy and beef herds as they are asymptomatic carriers. The aim of the present work was to assess the performance a real-time PCR (qPCR) method for the diagnosis of Campylobacter fetus in samples from bulls, comparing it with culture and isolation methods. 520 preputial samples were both cultured in Skirrow's medium and analyzed by qPCR. The estimated sensitivity of qPCR was 90.9% (95% CI, 69.4%–100%), and the specificity was 99.4% (95% CI, 98.6% - 100%). The proportion of C. fetus positive individuals was 2.1% by isolation and 2.5% by qPCR. Isolates were identified by biochemical tests as Cfv (n = 9) and Cff (n = 2). Our findings support the use of qPCR for fast and accurate detection of C. fetus directly from field samples of preputial smegma of bulls. The qPCR method showed to be suitable for massive screenings because it can be performed in pooled samples without losing accuracy and sensitivity.

Phylogenomic Analysis of Campylobacter fetus Reveals a Clonal Structure of Insertion Element ISCfe1 Positive Genomes

Subspecies of the species Campylobacter fetus are associated with specific host niches including mammals and reptiles. Campylobacter fetus subsp. fetus is a zoonotic pathogen infecting humans. Infections can vary from an acute intestinal illness to severe systemic infections, with sheep and cattle as major reservoirs. In contrast, Campylobacter fetus subsp. venerealis causes bovine genital campylobacteriosis, which leads to abortion in cattle and a high economic burden for the farmers. Therefore, high-quality molecular subtyping is indispensable for interventional epidemiology. We used whole-genome sequencing (WGS) data of 283 Campylobacter fetus strains from 18 countries and compared several methods for Campylobacter fetus subtyping, including WGS, multilocus sequence typing, PCR assays, and the presence of the insertion element ISCfe1. We identified a highly clonal clade (designated as clade 1) that harbors the insertion sequence ISCfe1. The presence of this insertion sequence is an essential diagnostic tool for the identification of the subspecies Campylobacter fetus subsp. venerealis, serving as a target for several PCR assays. However, we have found a high sequence variability for the ISCfe1 besides the presence of ISCfe1-paralogues in certain other genomes (n = 7) which may cause incorrect diagnostic results. Clade 1 seems to be the cattle-specific clade of this species. We propose that only this clade might be designated as Campylobacter fetus subsp. venerealis as it harbors the ISCfe1 marker sequence, which is a major target for molecular methods currently used for Campylobacter fetus subspecies identification. Fostering this proposal, we defined eleven stable nucleotide markers specific for this clade. Additionally, we developed a bioinformatics toolbox for the fast identification of this clade based on WGS data. In conclusion, our results demonstrate that WGS can be used for Campylobacter fetus subtyping overcoming limitations of current PCR and MLST protocols.

Effects of Campylobacter fetus on bull sperm quality

Campylobacter fetus is a gram-negative, motile, spiral or S-shaped bacterium, which induces campylobacteriosis. This disease causes decrease productivity of cattle. Although considerable research has been done on the role of C. fetus on female fertility, little is known about the effect on bulls. The aim of this work was to evaluate the effect of C. fetus subsp. fetus (Cff) and C. fetus subsp. venerealis (Cfv) on bull sperm quality. Samples of frozen semen (n = 29 straws) were each distributed into three groups: two of them incubated with the microorganism (Cff, Cfv) and a control group. The proportions of live spermatozoa, with functional membrane and true acrosomal reaction in control group were significantly (P < 0.01) greater than those observed in Cff and Cfv groups. However, no significant differences (P > 0.05) were found in sperm chromatin structure among treatments. In adhesion assay, proportions of spermatozoa with adhered Campylobacter were similar for both subspecies. Results confirm that Cff and Cfv have the same ability to bind in an irreversible way to bull spermatozoa and to affect sperm quality. It is proposed that adherence could be considered as the main cause of sperm alterations, and also an important step of pathogenesis and venereal transmission.

Influence of Protein Glycosylation on Campylobacter fetus Physiology

Campylobacter fetus is commonly associated with venereal disease and abortions in cattle and sheep, and can also cause intestinal or systemic infections in humans that are immunocompromised, elderly, or exposed to infected livestock. It is also believed that C. fetus infection can result from the consumption or handling of contaminated food products, but C. fetus is rarely detected in food since isolation methods are not suited for its detection and the physiology of the organism makes culturing difficult. In the related species, Campylobacter jejuni, the ability to colonize the host has been linked to N-linked protein glycosylation with quantitative proteomics demonstrating that glycosylation is interconnected with cell physiology. Using label-free quantitative (LFQ) proteomics, we found more than 100 proteins significantly altered in expression in two C. fetus subsp. fetus protein glycosylation (pgl) mutants (pglX and pglJ) compared to the wild-type. Significant increases in the expression of the (NiFe)-hydrogenase HynABC, catalyzing H₂-oxidation for energy harvesting, correlated with significantly increased levels of cellular nickel, improved growth in H₂ and increased hydrogenase activity, suggesting that N-glycosylation in C. fetus is involved in regulating the HynABC hydrogenase and nickel homeostasis. To further elucidate the function of the C. fetus pgl pathway and its enzymes, heterologous expression in Escherichia coli followed by mutational and functional analyses revealed that PglX and PglY are novel glycosyltransferases involved in extending the C. fetus hexasaccharide beyond the conserved core, while PglJ and PglA have similar activities to their homologs in C. jejuni. In addition, the pgl mutants displayed decreased motility and ethidium bromide efflux and showed an increased sensitivity to antibiotics. This work not only provides insight into the unique protein N-glycosylation pathway of C. fetus, but also expands our knowledge on the influence of protein N-glycosylation on Campylobacter cell physiology.

Polyclonal Campylobacter fetus Infections Among Unrelated Patients, Montevideo, Uruguay, 2013-2018

In Montevideo (2013-2018), 8 Campylobacter fetus extraintestinal infections were reported. The polyclonal nature of strains revealed by whole-genome sequencing and the apparent lack of epidemiological links was incompatible with a single contamination source, supporting alternative routes of transmission.

Campylobacter fetus Meningitis and Pyogenic Spondylodiscitis in a Healthy Young Woman

We report a rare case of Campylobacter fetus meningitis and pyogenic spondylodiscitis in a healthy young woman. A 35-year-old woman without significant medical history presented with fever, headache, and low back pain. C. fetus was detected from the blood culture. Cerebrospinal fluid analysis showed bacterial meningitis 2 days after onset. Although initial magnetic resonance imaging (MRI) did not reveal abnormal findings, repeated MRI showed a low-signal-intensity lesion on T1-weighted image (T1WI) and a high-signal-intensity lesion on T2WI between the L5 and S1 vertebral bodies 11 days after onset. The mode of infection was considered to be the consumption of raw chicken meat. After antibiotic treatment with 12 g/day ampicillin following 6 g/day meropenem, she was discharged 51 days after onset. As the inflammatory signs on MRI improved, oral antibiotic therapy was discontinued 85 days after onset. Although the initial MRI showed no abnormal findings, repeat MRI should be performed for patients who have persistent low back pain and fever.

Meningoencephalitis Caused by a Campylobacter fetus in a Patient with Chronic Alcoholism

We herein report a case of Campylobacter fetus meningoencephalitis in a patient with chronic alcoholism. C. fetus is a rare cause of meningitis. The patient presented with hallucinations and monology, and alcohol withdrawal was initially suspected. After he was unsuccessfully treated for alcohol withdrawal delirium, we diagnosed C. fetus meningoencephalitis. Ampicillin monotherapy gradually improved his clinical status. A previous report stated that C. fetus infection is associated with chronic alcoholism. In patients with chronic alcoholism and disturbed consciousness, an atypical bacterial central nervous system infection, such as C. fetus meningoencephalitis, should be considered.

Differentiation of Campylobacter fetus Subspecies by Proteotyping

Campylobacter fetus is a causative agent of intestinal illness and, occasionally, severe systemic infections and meningitis. C. fetus currently comprises three subspecies: C. fetus subspecies fetus (Cff), C. fetus subspecies venerealis (Cfv), and C. fetus subspecies testudinum (Cft). Cff and Cfv are primarily associated with mammals whereas Cft is associated with reptiles. To offer an alternative to laborious sequence-based techniques such as multilocus sequence typing (MLST) and polymerase chain reaction (PCR)-ribotyping for this species, the purpose of the study was to develop a typing scheme based on proteotyping. In total, 41 representative C. fetus strains were analyzed by intact cell mass spectrometry and compared to MLST results. Biomarkers detected in the mass spectrum of C. fetus subsp. fetus reference strain LMG 6442 (NCTC 10842) as well as corresponding isoforms were associated with the respective amino acid sequences and added to the C. fetus proteotyping scheme. In combination, the 9 identified biomarkers allow the differentiation of Cft subspecies strains from Cff and Cfv subspecies strains. Biomarkers to distinguish between Cff and Cfv were not found. The results of the study show the potential of proteotyping to differentiate different subspecies, but also the limitations of the method.

Successful Empiric Therapy for Postsplenectomy Sepsis with Campylobacter fetus in an Abattoir Worker with Follicular Lymphoma

Asplenia may yield an increased risk of fulminant sepsis with various pathogens. Human infection with Campylobacter fetus is rare, but it often presents with non-gastrointestinal tract infection among immunocompromised individuals. A 55-year-old abattoir worker presented with a fever. He had had splenectomy for follicular lymphoma and rituximab maintenance therapy by four months before the presentation. Blood cultures yielded C. fetus, and the administration of meropenem dissolved the bacteremia. Further maintenance therapy was withheld, and no recurrence of infection has been observed for seven years. Asplenia, occupational exposure, and/or rituximab maintenance therapy might have been precipitating factors of this rare infection.

Versatile nano-platform for tailored immuno-magnetic carriers

Custom immuno-magnetic devices are desirable tools for biomedical and biotechnological applications. Herein, surface active maghemite nanoparticles (SAMNs) are proposed as a versatile platform for developing tailored immuno-magnetic nano-carriers by simple wet reactions. Two examples for conjugating native and biotinylated antibodies were presented along with their successful applications in the recognition of specific foodborne pathogens. Nanoparticles were functionalized with rhodamine B isothiocyanate (RITC), leading to a fluorescent nano-conjugate, and used for binding anti-Campylobacter fetus antibodies (SAMN@RITC@Anti-Cf). The microorganism was selectively captured in the presence of two other Campylobacter species (C. jejuni and C. coli), as verified by PCR. Alternatively, SAMNs were modified with avidin, forming a biotin-specific magnetic nano-carrier and used for the immobilization of biotinylated anti-Listeria monocytogenes antibodies (SAMN@avidin@Anti-Lm). This immuno-magnetic carrier was integrated in piezoelectric quartz crystal microbalance (QCM) sensor for the detection of L. monocytogenes in milk, showing a detection limit of 3 bacterial cells. The present work presents a new category of customized immuno-magnetic nano-carriers as a competitive option for suiting specific applications. Graphical abstract ᅟ.

Intracranial Giant Mycotic Aneurysm without Endocarditis and Vasculitis: Report of Rare Entity and Review of Literature

BACKGROUND

Infectious aneurysm is a rare complication in intracranial aneurysm. Moreover, giant aneurysm is a rare entity in intracranial aneurysm. In the great majority of infectious intracranial aneurysms, vasculitis and/or endocarditis is associated.

CASE DESCRIPTION

Here, we report the case of an 83-year-old man who developed a giant infectious intracranial aneurysm on the anterior communicating artery. This patient had never shown any intracranial bleeding. A surgery was performed, and purulent liquid and aneurysm wall were removed during procedure. The bacteriologic analyses reported Campylobacter fetus.

CONCLUSIONS

This bacterium seems to be more and more frequent in North America and Europe, according to the current literature. Moreover, cases of mycotic extracranial aneurysm were reported. Here we report the first case of intracranial giant infectious aneurysm in an adult patient, without any endocarditis or vasculitis. This new entity could be the cause of a bacterial graft on an asymptomatic giant preexisting intracranial aneurysm or a consequence of campylobacteriosis.

Campylobacter fetus Cluster Among Men Who Have Sex With Men, Montreal, Quebec, Canada, 2014-2016

From March 2014 to December 2016, a cluster of 13 cases of Campylobacter fetus intestinal and extraintestinal infections, including 2 patients with an aortic mycotic aneurysm, caused significant morbidity. The cluster likely resulted from sexual transmission between men having sex with men living in the greater Montreal area, Quebec, Canada.

Identification of Campylobacter fetus by fluorescence in situ hybridization (FISH)

Two new DNA FISH-probes for Campylobacter fetus were designed, in silico checked for cross-reactions and successfully evaluated in a multi-centric approach with 41 Campylobacter fetus isolates including isolates of all three know subspecies: Campylobacter fetus ssp. fetus, Campylobacter fetus ssp. venerealis, and Campylobacter fetus ssp. testudinum and 40 strains of five non-target Campylobacter species.

Campylobacter fetus prosthetic valve endocarditis presenting as a stroke

Introduction

Campylobacter is a common pathogen of the gastrointestinal tract, but invasive disease is rare. Campylobacter fetus can play a role in osteomyelitis, meningitis and joint infection and has a prediliction for the vascular endothelium, causing mycotic aneurysms, thrombophlebitis and endocarditis. Here we present a case of prosthetic valve endocarditis caused by C. fetus and a review of the literature.

Case presentation

An 85-year-old woman with a tissue aortic valve replacement and atrial fibrillation was admitted to hospital with tonic-clonic seizures, right-sided hemiparesis, facial droop and hemianopia. Multiple cerebral emboli were seen on magnetic resonance imaging of the brain. Blood cultures grew C. fetus and an echocardiogram showed thickening and restricted movement of the aortic valve, a significant difference from an echocardiogram done 2 months before when the same organism was again isolated in blood cultures. She improved after treatment with 6 weeks of amoxicillin and 2 weeks of synergistic gentamicin for prosthetic valve endocarditis.

Conclusion

There have only been five previously reported cases of C. fetus prosthetic valve endocarditis and this is the only patient who presented as a stroke. The majority of surviving patients required replacement of the affected valve with only one other patient surviving in the absence of surgery. No guidelines exist on the optimum treatment of C. fetus endocarditis and this case reports adds to the growing literature on the appropriate management for this rare and potentially devastating disease.

Campylobacter fetus meningitis associated with eating habits of raw meat and raw liver in a healthy patient: A case report and literature review

Meningitis caused by the zoonotic pathogen Campylobacter fetus in immunocompetent adults is rare. We report a 48-year-old Japanese woman with no underlying disease who was found to have meningitis caused by C. fetus. Both C. fetus subsp. fetus and C. fetus subsp. venerealis were isolated from the cerebrospinal fluid culture. The mode of infection in our patient was considered to be associated with the consumption of raw beef and raw cattle liver on a regular basis. Public awareness and education to avoid the consumption of raw or undercooked meat might help prevent C. fetus meningitis.

A novel real-time PCR assay for quantitative detection of Campylobacter fetus based on ribosomal sequences

Background

Campylobacter fetus is a pathogen of major concern for animal and human health. The species shows a great intraspecific variation, with three subspecies: C. fetus subsp. fetus, C. fetus subsp. venerealis, and C. fetus subsp. testudinum. Campylobacter fetus fetus affects a broad range of hosts and induces abortion in sheep and cows. Campylobacter fetus venerealis is restricted to cattle and causes the endemic disease bovine genital campylobacteriosis, which triggers reproductive problems and is responsible for major economic losses. Campylobacter fetus testudinum has been proposed recently based on genetically divergent strains isolated from reptiles and humans. Both C. fetus fetus and C. fetus testudinum are opportunistic pathogens for immune-compromised humans. Biochemical tests remain as the gold standard for identifying C. fetus but the fastidious growing requirements and the lack of reliability and reproducibility of some biochemical tests motivated the development of molecular diagnostic tools. These methods have been successfully tested on bovine isolates but fail to detect some genetically divergent strains isolated from other hosts. The aim of the present study was to develop a highly specific molecular assay to identify and quantify C. fetus strains.

Results

We developed a highly sensitive real-time PCR assay that targets a unique region of the 16S rRNA gene. This assay successfully detected all C. fetus strains, including those that were negative for the cstA gene-based assay used as a standard for molecular C. fetus identification. The assay showed high specificity and absence of cross-reactivity with other bacterial species. The analytical testing of the assay was determined using a standard curve. The assay demonstrated a wide dynamic range between 10² and 107 genome copies per reaction, and a good reproducibility with small intra- and inter-assay variability.

Conclusions

The possibility to characterize samples in a rapid, sensitive and reproducible way makes this assay a good option to establish a new standard in molecular identification and quantification of C. fetus species.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-016-0913-3) contains supplementary material, which is available to authorized users.

Assessing the intra-species genetic variability in the clonal pathogen Campylobacter fetus: CRISPRs are highly polymorphic DNA markers

Campylobacter fetus is a Gram-negative, microaerophilic bacterium that infects animals and humans. The subspecies Campylobacter fetus subsp. fetus (Cff) affects a broad range of vertebrate hosts and induces abortion in cows and sheep. Campylobacter fetus subsp. venerealis (Cfv) is restricted to cattle and causes the endemic disease bovine genital campylobacteriosis, which triggers reproductive problems and is responsible for major economic losses. Campylobacter fetus subsp. testudinum (Cft) has been isolated mostly from apparently healthy reptiles belonging to different species but also from ill snakes and humans. Genotypic differentiation of Cff and Cfv is difficult, and epidemiological information is scarce because there are few methods to study the genetic diversity of the strains. We analyze the efficacy of MLST, ribosomal sequences (23S gene and internal spacer region), and CRISPRs to assess the genetic variability of C. fetus in bovine and human isolates. Sequences retrieved from complete genomes were included in the analysis for comparative purposes. MLST and ribosomal sequences had scarce or null variability, while the CRISPR-cas system structure and the sequence of CRISPR1 locus showed remarkable diversity. None of the sequences here analyzed provided evidence of a genetic differentiation of Cff and Cfv in bovine isolates. Comparison of bovine and human isolates with Cft strains showed a striking divergence. Inter-host differences raise the possibility of determining the original host of human infections using CRISPR sequences. CRISPRs are the most variable sequences analyzed in C. fetus so far, and constitute excellent representatives of a dynamic fraction of the genome. CRISPR typing is a promising tool to characterize isolates and to track the source and transmission route of C. fetus infections.

Whole genome sequence analysis indicates recent diversification of mammal-associated Campylobacter fetus and implicates a genetic factor associated with H2S production

Background

Campylobacter fetus (C. fetus) can cause disease in both humans and animals. C. fetus has been divided into three subspecies: C. fetus subsp. fetus (Cff), C. fetus subsp. venerealis (Cfv) and C. fetus subsp. testudinum (Cft). Subspecies identification of mammal-associated C. fetus strains is crucial in the control of Bovine Genital Campylobacteriosis (BGC), a syndrome associated with Cfv. The prescribed methods for subspecies identification of the Cff and Cfv isolates are: tolerance to 1 % glycine and H₂S production.

Results

In this study, we observed the deletion of a putative cysteine transporter in the Cfv strains, which are not able to produce H₂S from L-cysteine. Phylogenetic reconstruction of the core genome single nucleotide polymorphisms (SNPs) within Cff and Cfv strains divided these strains into five different clades and showed that the Cfv clade and a Cff clade evolved from a single Cff ancestor.

Conclusions

Multiple C. fetus clades were observed, which were not consistent with the biochemical differentiation of the strains. This suggests the need for a closer evaluation of the current C. fetus subspecies differentiation, considering that the phenotypic differentiation is still applied in BGC control programs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-3058-7) contains supplementary material, which is available to authorized users.

Infectious reproductive disease pathogens in dairy herd bulls

OBJECTIVE

Investigate the presence of infectious reproductive disease pathogens in dairy herd bulls in south-west Victoria, Australia, using a cross-sectional study.

METHODS

Dairy herd bulls from 32 herds were sampled for bovine viral diarrhoea virus (BVDV: 256 bulls, 32 herds) prior to the natural mating period, bovine herpes virus-1 prior to (10 bulls, 5 herds) and after (118 bulls, 19 herds) the natural mating period, and for Campylobacter fetus spp. and Tritrichomonas foetus after the natural mating period (61 bulls, 7 herds). BVDV was detected from an ear-notch sample using a commercially available rapid assay ELISA, bovine herpes virus-1 and T. foetus were screened for by PCR from a penile swab and preputial sample respectively, and C. fetus spp. were screened for by culture of preputial samples.

RESULTS

None of the bulls tested positive for BVDV antigen. Campylobacter fetus venerealis (or C. fetus fetus) was cultured in 6.6% (4/61) of bulls, representing 2 of the 7 (28.6%) farms that were not vaccinating bulls against bovine genital campylobacteriosis. Bovine herpes virus-1 was identified in 7.8% (10/128) bulls sampled; T. foetus was not identified in any samples.

CONCLUSION

Bovine genital campylobacteriosis is present in south-western Victoria, despite longstanding recommendations to vaccinate bulls. Screening bulls for persistent infection with BVDV is probably justified, despite the absence of persistently infected bulls in this study. Further research is warranted to investigate the potential reproductive implications of BHV-1, and the presence of T. foetus.

Tubo-ovarian abscess with endometrial cyst probably infected by Campylobacter fetus: Two cases

Campylobacter fetus often causes systemic infection in immunocompromised or older patients, and prenatal infection, but Campylobacter has rarely been reported as a cause of adnexitis in healthy young women. Here we report two cases of endometriotic cysts infected by C. fetus for the first time. In case 1, a 28-year-old woman with a left adnexal cyst was hospitalized for left tubo-ovarian abscess and underwent left salpingo-oophorectomy. In case 2, a 22-year-old woman with a right adnexal cyst was hospitalized for a bilateral tubo-ovarian abscess and underwent right salpingo-oophorectomy and left salpingectomy. In both cases, C. fetus was detected on culture, and histopathology indicated a purulent endometriotic cyst. The present findings suggest that endometriotic cyst can be a focus of C. fetus infection.

[Efficiency of bacteriological culture and the immunofluorescent assay to detect Campylobacter fetus in bovine genital fluids]

Bovine genital campylobacteriosis is a reproductive disease that affects cattle production. It is caused by Campylobacter fetus subspecies, C. fetus fetus (Cff) and C. fetus venerealis (Cfv). The aim of this study was to identify the presence of C. fetus in genital fluids by bacteriological culture and direct immunofluorescence (DIF) and to compare the results. Two groups of 6 heifers and 5 bulls, one infected with Cff (Cff group) and the other with Cfv (Cfv group) were formed. Two heifers and 2 bulls, all of them uninfected, made up the control group. Samples of cervicovaginal mucus and preputial fluid were processed by culture and DIF. In the Cff group, 100% of the heifers and 80% of the bulls were infected, while in the Cfv group, 50% of the heifers and 60% of the bulls were infected. The degree of agreement (Kappa values) from benchmarking diagnostic techniques were 0.57 for heifers in the Cff group and 0.52 for heifers in the Cfv group, whereas the values for bulls were 0.17 and 0.27, respectively. Heifers yielded more positive results in the DIF assay than in the culture, exhibiting 5.6% increase in the Cff group and 7.4% in the Cfv group. The lowest percentage of positive results for DIF in bulls, 40% less for the Cff group and 5.2% for the Cfv group, could be due to improper sampling. Kappa values showed moderate agreement for the heifers and low for the bulls.

The susceptibility of Campylobacter concisus to the bactericidal effects of normal human serum

Campylobacter concisus is an emerging pathogen of the gastrointestinal tract that has been associated with Barrett's oesophagus, enteritis and inflammatory bowel disease. Despite having invasive potential in intestinal epithelial cells in-vitro, bacteraemic cases with C. concisus are extremely scarce, having only been reported once. Therefore, we conducted a serum resistance assay to investigate the bactericidal effects of human complement on C. concisus in comparison to some other Campylobacter species. In total, 22 Campylobacter strains were tested by incubation with normal human serum and subsequent cultivation in microaerobic conditions for 48 hours. Killing time was evaluated by decrease in total CFU over time for incubation with different serum concentrations. Faecal isolates of C. concisus showed inoculum reduction to less than 50% after 30 min. Campylobacter jejuni was sensitive to serum, but killing was delayed and a bacteraemic Campylobacter fetus subsp. fetus isolate was completely serum resistant. Interestingly, sensitivity of enteric C. concisus to human serum was not associated to different faecal-calprotectin levels. We find that faecal isolates of C. concisus are sensitive to the bactericidal effects of serum, which may explain why C. concisus is not associated to bacteraemia.

Campylobacter fetus infections in humans: exposure and disease

Campylobacter fetus can cause intestinal illness and, occasionally, severe systemic infections. Infections mainly affect persons at higher risk, including elderly and immunocompromised individuals and those with occupational exposure to infected animals. Outbreaks are infrequent but have provided insight into sources. Source attribution of sporadic cases through case-control interviews has not been reported. The reservoirs for C. fetus are mainly cattle and sheep. Products from these animals are suspected as sources for human infections. Campylobacter fetus is rarely isolated from food, albeit selective isolation methods used in food microbiology are not suited for its detection. We hypothesize that the general population is regularly exposed to C. fetus through foods of animal origin, cross-contaminated foodstuffs, and perhaps other, as yet unidentified, routes. Campylobacter fetus infection should be suspected particularly in patients with nonspecific febrile illness who are immunocompromised or who may have been occupationally exposed to ruminants.

Human infections with new subspecies of Campylobacter fetus

Campylobacter fetus subsp. testudinum subsp. nov. is a newly proposed subspecies of C. fetus with markers of reptile origin. We summarize epidemiologic information for 9 humans infected with this bacterium. All cases were in men, most of whom were of Asian origin. Infection might have been related to exposure to Asian foods or reptiles.

[Campylobacter fetus endocarditis: a case report]

Campylobacter are known to be a cause of enteritidic infections but Campylobacter fetus is more often a cause of systemic infections, mainly in fragilized patients. We report a C. fetus endocarditis. The prognosis seemstobe improved by a prolonged betalactam antibiotic treatment.

Herd-level risk factors for Campylobacter fetus infection, Brucella seropositivity and within-herd seroprevalence of brucellosis in cattle in northern Nigeria

Brucellosis and campylobacteriosis are economically important diseases affecting bovine reproductive efficiency in Nigeria. A questionnaire-based survey was conducted in 271 cattle herds in Adamawa, Kaduna and Kano states of northern Nigeria using multistage cluster sampling. Serum from 4745 mature animals was tested for Brucella antibodies using the Rose-Bengal plate test and positives were confirmed in series-testing protocol using competitive enzyme-linked immunosorbent assay. Preputial scrapings from 602 bulls were tested using culture and identification for Campylobacter fetus. For each disease, a herd was classified as positive if one or more animals tested positive. For each herd, information on potential managemental and environmental risk factors was collected through a questionnaire administered during an interview with the manager, owner or herdsman. Multiple logistic regression models were used to model the odds of herd infection for each disease. A zero-inflated Poisson model was used to model the count of Brucella-positive animals within herds, with the number tested as an exposure variable. The presence of small ruminants (sheep and/or goats) on the same farm, and buying-in of >3 new animals in the previous year or failure to practice quarantine were associated with increased odds of herd-level campylobacteriosis and brucellosis, as well as increased within-herd counts of Brucella-positive animals. In addition, high rainfall, initial acquisition of animals from markets, practice of gynaecological examination and failure to practice herd prophylactic measures were positively associated with the odds of C. fetus infection in the herd. Herd size of >15, pastoral management system and presence of handling facility on the farm were associated with increased odds, and gynaecological examination with reduced odds of herd-level Brucella seropositivity. Furthermore, the zero-inflated Poisson model showed that borrowing or sharing of bulls was associated with higher counts, and provision of mineral supplement with lower counts of Brucella-positive cattle within herds. Identification of risk factors for bovine campylobacteriosis and brucellosis can help to identify appropriate control measures, and the use of zero-inflated count model can provide more specific information on these risk factors.

A Case of Pyogenic Spondylodiscitis Caused by Campylobacter fetus for Which Early Diagnosis by Magnetic Resonance Imaging Was Difficult

The purpose of this case report was to report a rare case of pyogenic spondylodiscitis caused by Campylobacter fetus. A 37-year-old male presented with fever and low back pain. By lumbar magnetic resonance imaging (MRI), no abnormal finding was observed at the first presentation. However, low back pain was aggravated, and fever did not improve. Thus, lumbar MRI was repeated on the 26 day after the onset of symptoms, showing abnormal signals at vertebrae and disc spaces, and pyogenic spondylitis was diagnosed. The possibility of pyogenic spondylodiscitis should be taken into account if a patient presents with low back pain and fever, and areas of low signal intensity on a T1-weighted MRI should be carefully examined. When initial MRI does not reveal abnormal findings, repeated MRI after one or two weeks or, more favorably, immediate gadolinium enhancement MRI, are important for patients who have persistent low back pain and fever.

Mycotic abdominal aneurysm caused by campylobacter fetus: a case report for surgical management

We report a rare case of mycotic abdominal aortic aneurysm associated with Campylobacter fetus. A 72-year-old male admitted to the hospital because of pain in the right lower quadrant with pyrexia. The enhanced abdominal computed tomography (CT) examination showed abdominal aortic aneurysm (AAA) measuring 50 mm in maximum diameter and a high-density area of soft tissue density from the right lateral wall to the anterior wall of the aorta. However, since the patient showed no significant signs of defervescence after antibiotics administration, so we performed emergency surgery on the patient based on the diagnosis of impending rupture of mycotic AAA. The aneurysm was resected in situ reconstruction using a bifurcated albumin-coated knitted Dacron graft was performed. The cultures of blood and aneurysmal wall grew Campylobacter fetus, allowing early diagnosis and appropriate surgical management in this case, and the patient is making satisfactory progress. This is the fifth report of mycotic AAA characterizing culture positive for Campylobacter fetus in blood and tissue culture of the aortic aneurysm wall.