ABSTRACT
BACKGROUND: Campylobacter fetus subspecies fetus (CFF) is an important pathogen for both cattle and humans. We performed a systematic epidemiological and clinical study of patients and evaluated the genetic relatedness of 17 human and 17 bovine CFF isolates by using different genotyping methods. In addition, the serotype, the dissemination of the genomic island containing a type IV secretion system (T4SS) and resistance determinants for tetracycline and streptomycin were also evaluated. METHODS: The isolates from patients diagnosed with CFF infection as well as those from faecal samples of healthy calves were genotyped using pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), as well as single locus sequence typing (SLST) targeting cmp1 and cmp2 genes encoding two major outer membrane proteins in CFF. The presence of the genomic island and identification of serotype was determined by PCRs targeting genes of the T4SS and the sap locus, respectively. Tetracycline and streptomycin resistance phenotypes were determined by minimal inhibitory concentration. Clinical data obtained from medical records and laboratory data were supplemented by data obtained via telephone interviews with the patients and treating physicians. RESULTS: PFGE analysis defined two major clusters; cluster A containing 16 bovine (80 %) isolates and cluster B containing 13 human (92 %) isolates, suggesting a host preference. Further genotypic analysis using MLST, SLST as well as sap and T4SS PCR showed the presence of genotypically identical isolates in cattle and humans. The low diversity observed within the cmp alleles of CFF corroborates the clonal nature of this pathogen. The genomic island containing the tetracycline and streptomycin resistance determinants was found in 55 % of the isolates in cluster A and correlated with phenotypic antibiotic resistance. CONCLUSIONS: Most human and bovine isolates were separated on two phylogenetic clusters. However, several human and bovine isolates were identical by diverse genotyping methods, indicating a possible link between strains from these two hosts.
Subject(s)
Campylobacter Infections/epidemiology , Campylobacter fetus/drug effects , Campylobacter fetus/genetics , Drug Resistance, Bacterial/genetics , Adult , Aged , Aged, 80 and over , Animals , Anti-Bacterial Agents/pharmacology , Campylobacter Infections/drug therapy , Campylobacter Infections/microbiology , Campylobacter Infections/veterinary , Campylobacter fetus/pathogenicity , Cattle , Drug Resistance, Bacterial/drug effects , Electrophoresis, Gel, Pulsed-Field , Female , Genotype , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Multilocus Sequence Typing , Phenotype , Phylogeny , Polymerase Chain Reaction , Streptomycin/pharmacology , Switzerland/epidemiology , Tetracycline/pharmacologyABSTRACT
An unusual increase in the number of Campylobacter concisus isolates found in stool cultures provoked an outbreak investigation at Bern University Hospital. No epidemiological links were found between the cases, and the Campylobacter isolates were clonally unrelated. A change in culture conditions to a hydrogen-rich atmosphere enhancing growth of C. concisus was deemed responsible for this pseudo-outbreak.
Subject(s)
Bacteriological Techniques/methods , Campylobacter Infections/epidemiology , Campylobacter Infections/microbiology , Campylobacter/isolation & purification , Feces/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cluster Analysis , Female , Hospitals, University , Humans , Infant , Male , Middle Aged , Molecular Epidemiology , Molecular Typing , Switzerland/epidemiology , Young AdultABSTRACT
This case describes evidence for a Shiga toxin-producing Escherichia coli (STEC) O146:H28 infection leading to hemolytic uremic syndrome in a neonate. STEC O146:H28 was linked hitherto with asymptomatic carriage in humans. Based on strain characteristics and genotyping data, the mother is a healthy carrier who transmitted the STEC during delivery. STEC strains belonging to the low-pathogenic STEC group must also be considered in the workup of neonatal hemolytic uremic syndrome.
Subject(s)
Escherichia coli Infections/transmission , Hemolytic-Uremic Syndrome/microbiology , Shiga-Toxigenic Escherichia coli/isolation & purification , Anticonvulsants/therapeutic use , Carrier State/microbiology , Escherichia coli Infections/microbiology , Feces/microbiology , Humans , Infant, Newborn , Infectious Disease Transmission, Vertical , Male , Seizures/diagnosis , Seizures/drug therapy , Shiga Toxin 2/genetics , Shiga-Toxigenic Escherichia coli/genetics , Shiga-Toxigenic Escherichia coli/pathogenicityABSTRACT
Bacteria known in animal infectious diseases can cause challenges in human diagnostic laboratories. We present pitfalls in the identification and susceptibility testing of Staphylococcus hyicus, a pathogen that typically causes exudative epidermitis in pigs. In this case, the coagulase-positive staphylococcus isolated from a septic patient was misidentified as Staphylococcus aureus.
Subject(s)
Bacteremia/diagnosis , Bacteremia/microbiology , Staphylococcal Infections/diagnosis , Staphylococcal Infections/microbiology , Staphylococcus hyicus/isolation & purification , Animals , Bacteremia/pathology , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Humans , Middle Aged , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Staphylococcal Infections/pathology , Staphylococcus hyicus/classification , Staphylococcus hyicus/geneticsABSTRACT
A 29-year-old man complained of a 2-day history of frontal headache and new-onset fever but no other symptoms. Two months prior to admission, he underwent his third kidney transplantation. Clinical and laboratory examinations were unremarkable. Brain MRI showed a meningeal irritation consistent with viral meningitis. A diagnosis of cryptococcal meningitis and fungaemia was made after detection of a remarkably high and visible load of Cryptococcus neoformans in the cerebrospinal fluid.