Emergence of a genetically distinct, multidrug-resistant
Staphylococcus capitis
clone (NRCS-A) present in neonatal intensive care units has recently been extensively reported. The aims of the present ...study were to investigate which clones of
S. capitis
isolated from blood in a Swedish neonatal intensive care unit (NICU) have been present since 1987 and to investigate whether the NRCS-A clone has disseminated in Sweden. All
S. capitis
isolates from blood cultures of neonates (≤ 28 days of age) between 1987 and 2017 (
n
= 46) were whole-genome sequenced, and core genome multilocus sequence typing (cgMLST) was performed. Single-nucleotide polymorphism (SNP)-based phylogenetic relationships between the
S. capitis
isolates and in silico predictions of presence of genetic traits specific to the NRCS-A clone were identified. Furthermore, antibiotic susceptibility testing, including screening for heterogeneous glycopeptide-intermediate resistance, was performed. Thirty-five isolates clustered closely to the isolates previously determined as belonging to the NRCS-A clone and had fewer than 81 core genome loci differences out of 1063. Twenty-one of these isolates were multidrug resistant. The NRCS-A clone was found in 2001. Six pairs of isolates had differences of fewer than two SNPs. Genetic traits associated with the NRCS-A clone such as
nsr
,
ebh
,
tarJ
, and CRISPR were found in all 35 isolates. The increasing incidence of
S. capitis
blood cultures of neonates is predominantly represented by the NRSC-A clone at our NICU in Sweden. Furthermore, there were indications of transmission between cases; adherence to basic hygiene procedures and surveillance measures are thus warranted.
Staphylococcus capitis is a coagulase-negative staphylococcus that has been described primarily as causing bloodstream infections in neonatal intensive care units (NICUs), but has also recently been ...described in prosthetic joint infections (PJIs). The multidrug-resistant S. capitis subsp. urealyticus clone NRCS-A, comprising three sublineages, is prevalent in NICUs across the world, but its impact on other patient groups such as those suffering from PJIs or among adults planned for arthroplasty is unknown. Genome sequencing and subsequent analysis were performed on a Swedish collection of PJI isolates (n = 21), nasal commensals from patients planned to undergo arthroplasty (n = 20), NICU blood isolates (n = 9), operating theatre air isolates (n = 4), and reference strains (n = 2), in conjunction with an international strain collection (n = 248). The NRCS-A Outbreak sublineage containing the composite type V SCCmec-SCCcad/ars/cop element was present in PJIs across three Swedish hospitals. However, it was not found among nasal carrier strains, where the less virulent S. capitis subsp. capitis was most prevalent. The presence of the NRCS-A Outbreak clone in adult patients with PJIs demonstrates that dissemination occurs beyond NICUs. As this clone has several properties which facilitate invasive infections in patients with medical implants or immunosuppression, such as biofilm forming ability and multidrug resistance including heterogeneous glycopeptide-intermediate susceptibility, further research is needed to understand the reservoirs and distribution of this hospital-associated pathogen.
The use of conventional antibiotics has substantial clinical efficacy, however these vital antimicrobial agents are becoming less effective due to the dramatic increase in antibiotic-resistant ...bacteria. Novel approaches to combat bacterial infections are urgently needed and bacteriocins represent a promising alternative. In this study, the activities of the two-peptide bacteriocin PLNC8 αβ were investigated against different Staphylococcus spp. The peptide sequences of PLNC8 α and β were modified, either through truncation or replacement of all L-amino acids with D-amino acids. Both L- and D-PLNC8 αβ caused rapid disruption of lipid membrane integrity and were effective against both susceptible and antibiotic resistant strains. The D-enantiomer was stable against proteolytic degradation by trypsin compared to the L-enantiomer. Of the truncated peptides, β1-22, β7-34 and β1-20 retained an inhibitory activity. The peptides diffused rapidly (2 min) through the bacterial cell wall and permeabilized the cell membrane, causing swelling with a disorganized peptidoglycan layer. Interestingly, sub-MIC concentrations of PLNC8 αβ substantially enhanced the effects of different antibiotics in an additive or synergistic manner. This study shows that PLNC8 αβ is active against Staphylococcus spp. and may be developed as adjuvant in combination therapy to potentiate the effects of antibiotics and reduce their overall use.
Staphylococcus epidermidis is an important cause of bloodstream infections in patients with hematological malignancies. Knowledge of the long-term epidemiology of these infections is limited. We ...surveyed all S. epidermidis blood culture isolates from patients treated for hematological malignancies at the University Hospital of Örebro, Sweden from 1980 to 2009. A total of 373 S. epidermidis isolates were identified and multilocus sequence typing, staphylococcal chromosome cassette mec (SCCmec) typing and standard antibiotic susceptibility testing were employed to characterize these isolates. The majority of the isolates 361/373 (97%) belonged to clonal complex 2, and the 373 isolates were divided into 45 sequence types (STs); Simpson's Diversity Index was 0.56. The most prevalent STs were ST2 (243/373, 65%) and ST215 (28/373, 8%). Ninety three percent (226/243) of the ST2 isolates displayed either SCCmec type III or IV. ST2 and 215 were isolated during the entire study period, and together these STs caused temporal peaks in the number of positive blood cultures of S. epidermidis. Methicillin resistance was detected in 213/273 (78%) of all isolates. In the two predominating STs, ST2 and ST215, methicillin resistance was detected in 256/271 isolates (95%), compared with 34/100 (34%) in other STs (p<0.001). In conclusion, in this long-term study of patients with hematological malignancies, we demonstrate a predominance of methicillin-resistant ST2 among S. epidermidis blood culture isolates.
Carbapenem antibiotics are one of the last-resort agents against multidrug-resistant (MDR) bacteria. The occurrence of carbapenemase-producing Enterobacteriaceae (CPE) in wastewater and aquatic ...environments is an indication of MDR bacteria in the community. This study evaluated CPE in aquatic environments and compared them to the local hospital isolates in Sweden. Phenotypic and genotypic analyses of antibiotic resistance of environmental and clinical CPE were performed. The relatedness of the isolates and possible clonal dissemination was evaluated using phylogenetic and phyloproteomic analysis.
Klebsiella oxytoca
carrying carbapenemase genes (
bla
VIM-1
,
bla
IMP-29
) were isolated from wastewater and the recipient river, while
K. oxytoca
(
bla
VIM-1
) and
Klebsiella pneumoniae
(
bla
VIM-1
,
bla
OXA-48
,
bla
NDM-1
,
bla
KPC-3
) were isolated from patients at the local clinics or hospital. The
K. oxytoca
classified as sequence type 172 (ST172) isolated from the river was genotypically related to two clinical isolates recovered from patients. The similarity between environmental and clinical isolates suggests the dispersion of
bla
VIM-1
producing
K. oxytoca
ST172 from hospital to aquatic environment and the likelihood of its presence in the community. This is the first report of CPE in aquatic environments in Sweden; therefore, surveillance of aquatic and hospital environments for CPE in other urban areas is important to determine the major transfer routes in order to formulate strategies to prevent the spread of MDR bacteria.
The anaerobic Gram-positive coccus
is a rare cause of infections of bone and joints. The aim of this study was to describe the microbiological and clinical characteristics of orthopedic ...implant-associated infections caused by
We retrospectively analyzed samples consisting of anaerobic Gram-positive cocci and samples already identified as
from patients with orthopedic infections. The isolates found were determined to the species level using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The antibiotic susceptibility pattern was determined by Etest. Whole-genome sequencing (WGS) was performed. Clinical data were extracted from each patient's journal. In nine patients, orthopedic joint implant-associated infections were identified as being caused by
The isolates were susceptible to most of the antibiotics tested, with the exception of rifampin and moxifloxacin in a few cases. Five of the nine infections were monomicrobial. The most common antibiotic used to treat the infection was penicillin V, but five of the nine patients received a combination of antibiotics. Eight patients underwent surgical treatment, with extraction of the implant performed in seven cases and reimplantation in only two cases. The WGS showed a relatively small core genome, with 126,647 single nucleotide polymorphisms identified within the core genome. A phylogenomic analysis revealed that the isolates clustered into two distinct clades. Orthopedic implant-associated infections caused by
are rare, but the bacteria are generally susceptible to antibiotics. Despite this, surgical treatment combined with long-term antibiotics is often necessary. The WGS analysis revealed a high heterogeneity and suggested the existence of at least two different
species.
Further knowledge about the clinical and microbiological characteristics of prosthetic joint infections (PJIs) caused by different coagulase-negative staphylococci (CoNS) may facilitate ...interpretation of microbiological findings and improve treatment algorithms.
Staphylococcus capitis
is a CoNS with documented potential for both human disease and nosocomial spread. As data on orthopaedic infections are scarce, our aim was to describe the clinical and microbiological characteristics of PJIs caused by
S. capitis
. This retrospective cohort study included three centres and 21 patients with significant growth of
S. capitis
during revision surgery for PJI between 2005 and 2014. Clinical data were extracted and further microbiological characterisation of the
S. capitis
isolates was performed. Multidrug-resistant (≥3 antibiotic groups)
S. capitis
was detected in 28.6 % of isolates, methicillin resistance in 38.1 % and fluoroquinolone resistance in 14.3 %; no isolates were rifampin-resistant. Heterogeneous glycopeptide-intermediate resistance was detected in 38.1 %. Biofilm-forming ability was common. All episodes were either early post-interventional or chronic, and there were no haematogenous infections. Ten patients experienced monomicrobial infections. Among patients available for evaluation, 86 % of chronic infections and 70 % of early post-interventional infections achieved clinical cure; 90 % of monomicrobial infections remained infection-free. Genetic fingerprinting with repetitive sequence-based polymerase chain reaction (rep-PCR; DiversiLab®) displayed clustering of isolates, suggesting that nosocomial spread might be present.
Staphylococcus capitis
has the potential to cause PJIs, with infection most likely being contracted during surgery or in the early postoperative period. As
S. capitis
might be an emerging nosocomial pathogen, surveillance of the prevalence of PJIs caused by
S. capitis
could be recommended.
We report a sudden increase in the number of cases of C. canimorsus bacteremia during 3 months in 2022 at Östersund Hospital, Sweden. Prior to these cases, the most recent one in the region occurred ...in 2015. Among the five cases, one suffered from meningitis and one was diagnosed as endocarditis. Dog contact was present in all cases, although dog bites could only be verified in two. Improved diagnostics could not be an explanation to the surge, since the analysis method for blood culture had been the same since 2015. No corresponding increase was noted nationally, according to the Public Health Agency of Sweden. The isolates have been included in the ongoing global study with the aim to explore Capnocytophaga in humans and animals using comparative genomics and genome wide association studies. The study is supported by several ESCMID (European Society of Clinical Microbiology and Infectious Diseases) study groups.
Neisseria gonorrhoeae has developed resistance to most antimicrobials used for treatment. Worryingly, treatment failures with oral extended-spectrum cephalosporins (ESCs) have been reported, ...especially in the WHO Western Pacific Region, and susceptibility to all ESCs (oral and injectable), the last remaining treatment options in many settings, is decreasing globally.
To examine the emergence, spread and characteristics of Neisseria gonorrhoeae isolates with decreased susceptibility and resistance to ESCs in Sweden.
All available Swedish isolates from 1998-2009, collected from many countries worldwide, displaying decreased susceptibility to cefixime and/or ceftriaxone (minimum inhibitory concentration (MIC) ≥ 0.032 mg/l; n=331) were examined using antibiograms, full-length porB gene sequencing, N gonorrhoeae multi-antigen sequence typing (NG-MAST), and sequencing of ESC resistance determinants (penA, mtrR and porB1b (penB alteration)).
Based on EUCAST breakpoints, 30 (9.1%) and one (0.3%) of the isolates displayed in vitro resistance to cefixime and ceftriaxone, respectively. penA mosaic alleles and penA A501 alteration were detected in 24% and 11%, respectively, of the isolates, and in increasing prevalence over the years. Moreover, among these isolates 38 NG-MAST sequence type (STs) were detected, with ST1407 (n=29), ST1103 (n=9) and ST3378 (n=8) being most common.
The proportions of N gonorrhoeae isolates with decreased susceptibility and resistance to ESCs have substantially increased over the years in Sweden. Both penA mosaic alleles and the penA A501 alteration, together with mtrR and penB, are important for the decreased susceptibility and resistance to ESCs. At least one gonococcal penA mosaic strain (ST1407), including its evolving subtypes, with decreased susceptibility/resistance to ESCs circulates worldwide.
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