Antimicrobial susceptibilities of Campylobacter sp strains isolated from humans in 2005 to 2006 in Bielsko-Biala Region, Poland

Campylobacter jejuni and Campylobacter coli are frequent causes of bacterial gastroeneritis in humans worldwide. Campylobacteriois is usually a self-limiting disease and therapy with antibiotics is required in severe clinical infections. The objective [corrected] of this study was to determine the antibiotic resistance of C. jejuni and C. coli isolated from humans with diarrhea during 2005-2006 in Bielsko-Biala region in Poland. The MICs of ciprofloxacin, tetracycline, erythromycin, gentamicin and ampicillin were determined by the E-test method. It was observed that 23 % and 6% C. jejuni isolates were resistant to two and three antibiotics, respectively. All isolates of Campylobacter sp. were sensitive to erythromycin and gentamicin. From the 69 C. jejuni strains 58% were resistant to ciprofloxacin, 23% to tetracycline and 17% to ampicillin. From the 8 C. coli strains all were resistant to ciprofloxacin, 62,5% to ampicillin and 12,5% to tetracycline.     

Tigecicline susceptibilities of tetracycline-resistant Campylobacter jejuni clinical strains isolated in Poland

Campylobacteriosis is a significant public health problem in many developed countries. Campylobacter jejuni is one of the leading causes of food-borne gastroenteritis and enteritis in humans. Treatment of campylobacteriosis is required in severe clinical infections, extraintestinal infections and in immunocompromised patients. Erythromycin is the proposed drug of choice for the treatment of Campylobacter infections. However, tetracycline and fluoroquinolones (ciprofloxacin) are also clinically effective agents for treating infections caused by Campylobacter spp. High prevalence of C. jejuni resistant to fluoroquinolone and tetracycline have been recently reported in many countries. In human medicine new agents for the treatment of many serious infections are acutely needed in hospital practice. Tigecycline is a member of a new group of antibiotics--the glycylcyclines with an expanded microbiological spectrum. In our study we will determine the susceptibility of polish, resistant to tetracycline clinical C. jejuni isolates to tigecycline. All 94 tetracycline-resistant C. jejuni strains, with MICs between 8 and 256 mg/l, isolated between 2007 and 2008 were susceptible to tigecycline, with MICs 0.06 mg/1. Tigecycline may has potential therapeutic role in the treatment of serious Campylobacter infections.     

Diversities and similarities in PFGE profiles of Campylobacter jejuni isolated from migrating birds and humans

AIMS: To genetically sub-type Campylobacter jejuni strains isolated from migratory birds, and to compare these with clinical strains collected in the same area and corresponding time period, with the aim to increase our knowledge on sub-types occurring among wild birds and their possible impact on human disease. METHODS AND RESULTS: We sub-typed C. jejuni strains from migrating birds (n = 89) and humans (n = 47), using macrorestriction profiling by pulsed-field gel electrophoresis. Isolates from migrant birds often exhibited sub-types with higher levels of similarity to isolates from birds of the same species or feeding guild, than to isolates from other groups of birds. Likewise, could the vast majority of sub-types found among the migrant bird isolates not be identified among sub-types from human cases. Only two bird strains, one from a starling (Sturnus vulgaris) and one from a blackbird (Turdus merula), had sub-types that were similar to some of the human strain sub-types. CONCLUSIONS: Isolates from one bird species, or feeding guild, often exhibited high similarities, indicating a common transmission source for individuals, or an association between certain sub-types of C. jejuni and certain ecological guilds or phylogenetic groups of birds. Sub-types occurring among wild birds were in general distinctively different from those observed in patients. The two bird isolates that were similar to human strains were isolated from bird species that often live in close associations with human settlements. SIGNIFICANCE AND IMPACT OF STUDY: Wild birds have often been mentioned as a potential route for transmission of C. jejuni to humans. Our study demonstrates that strains isolated from birds most often are different from clinical strains, but that some strain similarities occur, notably in birds strongly associated with human activities.     

Prevalence of Campylobacter jejuni in Chicken Wings

Campylobacter jejuni was found in 82.9% of 94 chicken wing packages analyzed on the day of arrival at supermarkets and in 15.5% of 45 packages obtained from the supermarket shelves a few days later. The number of bacterial cells ranged from 10² to 10^3.9 per wing. The prevalence of C. jejuni in the wings varied with the brand, the day of sampling, and the age of the product.     

Prevalence of Campylobacter jejuni in chicken wings

Campylobacter jejuni was found in 82.9% of 94 chicken wing packages analyzed on the day of arrival at supermarkets and in 15.5% of 45 packages obtained from the supermarket shelves a few days later. The number of bacterial cells ranged from 10(2) to 10(3.9) per wing. The prevalence of C. jejuni in the wings varied with the brand, the day of sampling, and the age of the product.     

Campylobacter jejuni isolated from patas monkeys with diarrhea

Campylobacter jejuni was isolated from 11 (46%) of 24 patas monkeys with chronic diarrhea. Eight of these 11 (73%) monkey were characterized clinically by mucohemorrhagic diarrhea for periods up to a month followed by loose, semi-formed feces for a 12-month period. Half of the monkeys were treated with erythromycin for 10 days and the other half with tetracycline for 10 days, with all responding to treatment. Despite treatment, all monkeys again had an outbreak of mucohemorrhagic diarrhea. Biopsy specimens were taken from all eight monkeys over a period of 3 months. The clinical signs, treatment, and the gross and microscopic lesions seen in these monkeys were similar to those reported in humans and animals infected with Campylobacter jejuni.     

Comparison of genotypes and antibiotic resistance of Campylobacter jejuni isolated from humans and slaughtered chickens in Switzerland

Aims: To get an overview of genotypes and antibiotic resistances in Swiss Campylobacter jejuni implicated in human gastroenteritis and to examine the association with isolates from chickens. Methods and Results: Multilocus sequence typing (MLST) and flaB typing were applied to 136 human clinical isolates. Phenotypic resistance to 12 antimicrobials and genotypic resistance to macrolides and quinolones were determined. MLST resulted in 35 known and six new sequence types (ST). The flaB analysis revealed 35 different types, which – in combination with MLST – increased the resolution of the typing approach. Resistance to quinolones, tetracycline and ampicillin was found in 37·5, 33·1 and 8·1% of the isolates, respectively, whereas macrolide resistance was found only once. Genotypic and phenotypic resistance correlated in all cases. A comparison to Camp. jejuni isolated from slaughtered chickens was performed. While 86% of the quinolone‐sensitive human isolates showed overlapping MLST‐flaB types with those of chicken origin, resistant strains showed only 39% of matching types. Conclusion: Mainly quinolone‐sensitive Camp. jejuni strains implicated in human campylobacteriosis showed matching genotypes with isolates originating from chickens. Significance and Impact of the Study: A large proportion of human cases in Switzerland are likely to originate from domestic chickens, confirming that prevention measures in the poultry production are important.     

Pathophysiology of Campylobacter jejuni infections of humans

Campylobacter jejuni and closely related organisms are major causes of human bacterial enteritis. These infections can lead to extraintestinal disease and severe long-term complications. Of these, neurological damage, apparently due to the immune response of the host, is the most striking. This review examines current knowledge of the pathophysiology of the organism. Diversity of C. jejuni isolates in genotypic and phenotypic characteristics now is recognized and clinically relevant examples are presented. Expected future directions are outlined.     

Relationships between bacterial genotypes and in vitro virulence properties of Campylobacter jejuni and Campylobacter coli isolated from turkeys

AIMS: Campylobacter isolates from turkeys were genotyped and characterized by their in vitro virulence properties. Relationships between bacterial genotypes and virulence properties were analysed. METHODS AND RESULTS: Isolates were analysed by pulsed-field gel electrophoresis and fla typing. The toxin production was determined on the phenotypic level using a CHO-K1 cell culture model and on the genotypic level using PCR for detection of the cdtA, cdtB and cdtC genes. Although the cdtB gene was detected from 100% of the Campylobacter jejuni and Campylobacter coli isolates we observed three different morphological pictures on the cells. Cytotoxicity was associated with cell distension or cell rounding. All four Camp. coli strains and one Camp. jejuni strain did not produce any cytotoxic changes on the cells. Adhesion, invasion and survival of Campylobacter isolates were determined in a Caco-2 cell culture model. All isolates adhered to and invaded Caco-2 cells, whereas 64.7% of the strains survived for 48 h in the cells. CONCLUSION: Seventeen Campylobacter isolates from turkeys were classified into four groups with regard to their in vitro abilities. Jackknife analysis revealed a strong association between these groups and genotype clusters. SIGNIFICANCE AND IMPACT OF THE STUDY: Typing methods have generally failed to identify strains with specific virulence properties. This study suggests that a relationship between subgroups of Campylobacter with common in vitro virulence characteristics and genotypes exist.     

The heterogeneity of Campylobacter jejuni and Campylobacter coli strains isolated from healthy cattle

AIMS: To identify campylobacters isolated from clinically healthy cattle at species level by a multiplex polymerase chain reaction (m-PCR). The heterogeneity among Campylobacter jejuni and Campylobacter coli isolates was also investigated by using a restriction fragment length polymorphism (RFLP) analysis of flagellin (flaA) gene. METHODS AND RESULTS: Samples of intestinal contents, gall bladders, liver and faeces were collected from a total number of 1154 healthy cattle. The samples were inoculated onto Preston enrichment broth and agar. Of 1154 samples, 301 (26.1%) were positive for Campylobacter spp. Using an m-PCR assay for species identification, 179 (59.5%) were positive with C. jejuni specific primers while 30 (10%) were positive with C. coli specific primers. None of the liver samples examined was positive for C. jejuni or C. coli by mPCR. All the isolates identified as C. jejuni and C. coli were successfully subtyped by flaA typing. Of the 209 isolates tested, 28 different flaA types were found. Twenty-three flaA types were identified among 179 C. jejuni isolates and the remaining five from C. coli isolates. CONCLUSIONS: Although the overall results suggest that the degree of heterogeneity among the flaA genes of thermophilic Campylobacter strains isolated from healthy cattle is relatively high, they should be treated cautiously as the number of band types for C. coli was low and band type 8 in C. jejuni was represented by a high percentage (%58). SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of the present study suggest that healthy cattle can play role in the contamination of environment and human food chain by Campylobacter spp.     

Determination of toxicity of Campylobacter jejuni isolated from humans and from poultry carcasses acquired at various stages of production

AIM: The research focused on the determination of the toxicity variation associated with Campylobacter jejuni isolated from humans and chickens. METHODS AND RESULTS: Campylobacter jejuni isolates were obtained from chicken carcasses and from humans exhibiting symptoms of campylobacteriosis. Using HeLa cells as the in vitro model, toxicity was determined for each isolate. The mean toxicity level of the chicken isolates was significantly lower than that of the human isolates (P < 0.001). There was a wide range of toxicity in C. jejuni isolated from chickens and the percentage of isolates exhibiting low toxicity remaining relatively constant. All C. jejuni isolates from humans possessed either medium or high levels of toxicity. CONCLUSIONS: All wildtype C. jejuni isolates obtained from poultry carcasses may not be equally important as a human foodborne pathogen. SIGNIFICANCE AND IMPACT OF STUDY: Campylobacter jejuni remains a primary foodborne pathogen and increased efforts are needed to determine the impact of wildtype isolates in causing human illness. The present research indicates that all isolates may not be equally important in regards to disease potential. The information found should be included in efforts to develop C. jejuni detection, control and infection modelling.     

Speciating Campylobacter jejuni and Campylobacter coli isolates from poultry and humans using six PCR-based assays

Six previously published polymerase chain reaction (PCR) assays each targeting different genes were used to speciate 116 isolates previously identified as Campylobacter jejuni using routine microbiological techniques. Of the 116 isolates, 84 were of poultry origin and 32 of human origin. The six PCR assays confirmed the species identities of 31 of 32 (97%) human isolates and 56 of 84 (67%) poultry isolates as C. jejuni. Twenty eight of 84 (33%) poultry isolates were identified as Campylobacter coli and the remaining human isolate was tentatively identified as Campylobacter upsaliensis based on the degree of similarity of 16S rRNA gene sequences. Four of six published PCR assays showed 100% concordance in their ability to speciate 113 of the 116 (97.4%) isolates; two assays failed to generate a PCR product with four to 10 isolates. A C. coli-specific PCR identified all 28 hippuricase gene (hipO)-negative poultry isolates as C. coli although three isolates confirmed to be C. jejuni by the remaining five assays were also positive in this assay. A PCR-restriction fragment length polymorphism assay based on the 16S rRNA gene was developed, which contrary to the results of the six PCR-based assays, identified 28 of 29 hipO-negative isolates as C. jejuni. DNA sequence analysis of 16S rRNA genes from four hipO-negative poultry isolates showed they were almost identical to the C. jejuni type strain 16S rRNA sequences ATCC43431 and ATCC33560 indicating that assays reliant on 16S rRNA sequence may not be suitable for the differentiation of these two species.     

Genome analysis of Campylobacter jejuni strains isolated from a waterborne outbreak

Background

Waterborne Campylobacter jejuni outbreaks are common in the Nordic countries, and PFGE (pulsed field gel electrophoresis) remains the genotyping method of choice in outbreak investigations. However, PFGE cannot assess the clonal relationship between isolates, leading to difficulties in molecular epidemiological investigations. Here, we explored the applicability of whole genome sequencing to outbreak investigation by re-analysing three C. jejuni strains (one isolated from water and two from patients) from an earlier resolved Finnish waterborne outbreak from the year 2000.

Results

One of the patient strains had the same PFGE profile, as well as an identical overall gene synteny and three polymorphisms in comparison with the water strain. However, the other patient isolate, which showed only minor differences in the PFGE pattern relative to the water strain, harboured several polymorphisms as well as rearrangements in the integrated element CJIE2. We reconstructed the genealogy of these strains with ClonalFrame including in the analysis four C. jejuni isolated from chicken in 2012 having the same PFGE profile and sequence type as the outbreak strains. The three outbreak strains exhibited a paraphyletic relationship, implying that the drinking water from 2000 was probably contaminated with at least two different, but related, C. jejuni strains.

Conclusions

Our results emphasize the capability of whole genome sequencing to unambiguously resolve the clonal relationship between isolates of C. jejuni in an outbreak situation and evaluate the diversity of the C. jejuni population.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-768) contains supplementary material, which is available to authorized users.     

Antibmicrobial susceptibility of Serratia marcescens isolated from hospitalized patients in 2003 - 2005

500 strains of Serratia marcescens isolated in 2003-2005 were examined for drug susceptibility. By using several phenotypic methods it was shown that 67.6% of these strains produced ESBLs. Strains ESBL(-) and ESBL(+) were compared, paying special attention to their susceptibility to various antibiotics. It was revealed that strains ESBL(+) were much more resistant to majority of the investigated drugs. The biggest differences were in the case of amikacin and gentamicin, sensitive about 50% of ESBL(-) and 10% of ESBL(+), ciprofloxacin, sensitive 42% of ESBL(-) and 6.3% of ESBL(+) and trimethoprim/ sulphametoxazole, sensitive 45.8% of ESBL(-) and 9.4% of ESBL(+). Strains ESBL(-) retained a high susceptibility to ceftazidime (68.9%) and cefepime (71%). All strains ESBL(-) as well as ESBL(+) were susceptible to imipenem and meropenem. 78.9% of ESBL(-) and 67.3% of investigated ESBL(+) were susceptible to piperacillin/ tazobactam.     

Characterization of erythromycin resistance in Campylobacter coli and Campylobacter jejuni isolated from pig offal in New Zealand

AIMS: To determine the level and mechanism(s) of antimicrobial resistance in Campylobacter isolates obtained from human and environmental sources from South Canterbury, New Zealand. METHODS AND RESULTS: A total of 251 Campylobacter isolates were tested for susceptibility to ciprofloxacin, erythromycin, nalidixic acid and tetracycline using disc diffusion assays. Five pig offal isolates were observed to be highly erythromycin resistant, with minimal inhibitory concentrations determined to be >/=256 microg ml(-1). Nucleotide sequencing of the 23S ribosomal DNA (rDNA) in these resistant isolates identified an A --> G change at Escherichia coli position 2059 that has been previously implicated in erythromycin resistance in Campylobacter coli. Macrorestriction profiling using pulsed-field gel electrophoresis showed these isolates were nonclonal. CONCLUSIONS: The majority of Campylobacter isolates from South Canterbury remain sensitive to the most clinically relevant antimicrobial agents. Our results support other reports showing that specific variations in the 23S rDNA contribute to erythromycin resistance. SIGNIFICANCE AND IMPACTS OF THE STUDY: This study defines the baseline frequency of antimicrobial resistance associated with Campylobacter isolates from South Canterbury, and discusses the likely molecular mechanisms conferring erythromycin resistance in this organism. Resistance to erythromycin in these isolates is not linked to a dominant Campylobacter clone and has likely arisen independently in different genetic lines exposed to selective antimicrobial pressure.     

Prevalence and survival of Campylobacter jejuni in unpasteurized milk.

Campylobacter jejuni was isolated from 1 to 108 (0.9%) milk samples obtained from the bulk tanks of nine grade A dairy farms and from 50 of 78 (64%) cows producing grade A milk. Survival of eight Campylobacter strains in unpasteurized milk (4 degrees C) varied greatly: the most tolerant strain showed a less than 2-log10 decrease in viable cells after 14 days, and the most sensitive strain showed a greater than 6-log10 decrease after 7 days. One strain was still recoverable 21 days after the inoculation of milk. Inactivation of the different strains corresponded with an increase in milk aerobic plate count and a decrease in milk pH; however, no absolute correlation could be made between the rates of change of these parameters and the rates of campylobacter inactivation. When held at 4 degrees C, C. jejuni was most stable in brucella broth, died most rapidly in unpasteurized milk, and was inactivated at an intermediate rate in sterile milk. Our results indicate the presence and possible persistence of C. jejuni in raw grade A milk and reaffirm the need for pasteurization of milk.