Gitte Nyvang Hartmeyer

Multidrug-resistant Bacteroides fragilis group on the rise in Europe?

We report a case of multidrug-resistance (MDR) in a strain of Bacteroides fragilis from a blood culture and abdominal fluid in a Danish patient. The patient had not been travelling for several years and had not received antibiotics prior to the present case. We also summarize the cases that have been reported to date of MDR B. fragilis group in Europe. As far as we know, a case like this with MDR B. fragilis has not been described in Scandinavia before.

Pig-associated methicillin-resistant Staphylococcus aureus: family transmission and severe pneumonia in a newborn.

Abstract Carriage of pig-associated methicillin-resistant Staphylococcus aureus (MRSA) is known to occur in pig farmers. Zoonotic lineages of MRSA have been considered of low virulence and with limited capacity for inter-human spread. We present a case of family transmission of pig-associated MRSA ST398, which resulted in a severe infection in a newborn.

Direct 16S rRNA gene sequencing of polymicrobial culture-negative samples with analysis of mixed chromatograms.

Two cases involving polymicrobial culture-negative samples were investigated by 16S rRNA gene sequencing, with analysis of mixed chromatograms. Fusobacterium necrophorum, Prevotella intermedia and Streptococcus constellatus were identified from pleural fluid in a patient with Lemierres syndrome and Neisseria meningitidis and Escherichia coli were identified from a petechia in a patient with meningococcal disease.

Need for species-specific detection for the diagnosis of amoebiasis in a non-endemic setting.

Abstract The diagnosis of amoebiasis caused by Entamoeba histolytica is traditionally based on microscopy. However, the specificity of this method may be questioned, especially in areas where infections by E. histolytica are rare. In the present study, a species-specific real-time PCR was used for the identification of the morphologically similar species E. histolytica and Entamoeba dispar. Out of 15 microscopy-positive stool samples, all were negative for E. histolytica and positive for E. dispar. In 2 cases, a suspicion of amoebic liver abscesses was confirmed by detection of E. histolytica DNA in stored sample material. Microscopy alone is clearly insufficient for the detection of E. histolytica in a setting where this parasite is rare. Microscopy-positive stool samples should be further tested by species-specific tests to distinguish E. histolytica from the non-pathogenic parasite E. dispar. On specific suspicion of amoebiasis, such as the suspicion of amoebic liver abscesses, species-specific tests can be applied even after storage.

Molecular characterisation of the clonal emergence of high-level ciprofloxacin-monoresistant Haemophilus influenzae in the Region of Southern Denmark

Haemophilus influenzae is an important human pathogen usually susceptible to quinolones. Here we report the emergence of high-level ciprofloxacin-monoresistant H. influenzae in the Region of Southern Denmark. Four isolates were collected for phenotypic and molecular characterisation using whole-genome sequencing (WGS). During an 18-month period, the occurrence of high-level ciprofloxacin-monoresistant H. influenzae in patients aged 1-77 years from sputum, ear and eye samples was detected. An epidemiological link between the patients could not be identified. The isolates were non-encapsulated, biotype III and were demonstrated by WGS to be clonal belonging to a single clade with an unknown multilocus sequence type (double-locus variant of ST196). The antibiogram demonstrated that they were all monoresistant to ciprofloxacin with a minimum inhibitory concentration (MIC) >32mg/L. In silico resistome analysis revealed identical, both previously characterised and novel, putative resistance-related mutations in gyrA (S84L and D88N), parC (K20R, S84I, D356A or T356A, and M481I) and parE (E151K, I159A, D420N and S599A) in all isolates. The isolates were otherwise negative for any resistance genes. This is the first description of the clonal emergence of high-level monoresistant H. influenzae due to amino acid substitutions in gyrA, parC and parE.

Incidence of HACEK bacteraemia in Denmark: A 6-year population-based study

OBJECTIVES Bacteria with common microbiological and clinical characteristics are often recognized as a particular group. The acronym HACEK stands for five fastidious genera associated with infective endocarditis (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella). Data on the epidemiology of HACEK are sparse. This article reports a 6-year nationwide study of HACEK bacteraemia in Denmark. METHODS Cases of HACEK bacteraemia occurring during the years 2010-2015 were retrieved from the national Danish microbiology database, covering an average surveillance population of 5.6 million per year. RESULTS A total of 147 cases of HACEK bacteraemia were identified, corresponding to an annual incidence of 0.44 per 100000 population. The annual incidence for males was 0.56 per 100000 and for females was 0.31 per 100000. The median age was 56 years (range 0-97 years), with variation among the genera. One hundred and forty-three isolates were identified to the species level and six to the genus level: Haemophilus spp, n=55; Aggregatibacter spp, n=37; Cardiobacterium spp, n=9; Eikenella corrodens n=21; and Kingella spp, n=27. CONCLUSIONS This is the first study on the incidence of HACEK bacteraemia in a large surveillance population and may inspire further studies on the HACEK group. Haemophilus spp other than Haemophilus influenzae accounted for most cases of HACEK bacteraemia in Denmark, with Aggregatibacter spp in second place.

Cryptosporidium Species are Frequently Present but Rarely Detected in Clinical Samples from Children with Diarrhea in a Developed Country

Two studies were done on cryptosporidiosis in children. A retrospective survey showed that from 2005 to 2015, Cryptosporidium species was detected by microscopy of stool from 0.25% of children with diarrhea. In a subsequent prospective study, polymerase chain reaction detected Cryptosporidium species in 4 (1.3%) of 304 children. Cryptosporidium species is as frequent as other intestinal pathogens in childhood diarrhea. Testing is relevant.

Selecting PCR for the Diagnosis of Intestinal Parasitosis: Choice of Targets, Evaluation of In-House Assays, and Comparison with Commercial Kits

Microscopy of stool samples is a labour-intensive and inaccurate technique for detection of intestinal parasites causing diarrhoea and replacement by PCR is attractive. Almost all cases of diarrhoea induced by parasites over a nine-year period in our laboratory were due to Giardia lamblia, Cryptosporidium species, or Entamoeba histolytica detected by microscopy. We evaluated and selected in-house singleplex real-time PCR (RT-PCR) assays for these pathogens in 99 stool samples from patients suspected of having intestinal parasitosis tested by microscopy. The strategy included a genus-specific PCR assay for C. parvum and C. hominis, with subsequent identification by a PCR that distinguishes between the two species. G. lamblia was detected in five and C. parvum in one out of 68 microscopy-negative samples. The performance of the in-house RT-PCR assays was compared to three commercially available multiplex test (MT-PCR) kit systems in 81 stool samples, collected in 28 microscopy-positive and 27 microscopy-negative samples from individuals suspected of intestinal parasitosis and in 26 samples from individuals without suspicion of parasitic infection. The in-house assays detected parasites in more samples from patients suspected of having parasitosis than did any of the kits. We conclude that commercial kits are targeting relevant parasites, but their performance may vary.