The predominant community-associated MRSA strains vary between geographic settings, with ST8-IV USA300 being the commonest clone in North America, and the ST30-IV Southwest Pacific clone established ...as the dominant clone in New Zealand for the past two decades. Moreover, distinct epidemiological risk factors have been described for colonisation and/or infection with CA-MRSA strains, although these associations have not previously been characterized in New Zealand. Based on data from the annual New Zealand MRSA survey, we sought to describe the clinical and molecular epidemiology of MRSA in New Zealand. All non-duplicate clinical MRSA isolates from New Zealand diagnostic laboratories collected as part of the annual MRSA survey were included. Demographic data was collected for all patients, including age, gender, ethnicity, social deprivation index and hospitalization history. MRSA was isolated from clinical specimens from 3,323 patients during the 2005 to 2011 annual surveys. There were marked ethnic differences, with MRSA isolation rates significantly higher in Māori and Pacific Peoples. Over the study period, there was a significant increase in CA-MRSA, and a previously unidentified PVL-negative ST5-IV spa t002 clone replaced the PVL-positive ST30-IV Southwest Pacific clone as the dominant CA-MRSA clone. Of particular concern was the finding of several successful and virulent MRSA clones from other geographic settings, including ST93-IV (Queensland CA-MRSA), ST8-IV (USA300) and ST772-V (Bengal Bay MRSA). Ongoing molecular surveillance is essential to prevent these MRSA strains becoming endemic in the New Zealand healthcare setting.
For the USA alone, in 2012, the estimated attributable financial impact of SSIs in adults in acute care hospitals was almost US$3·3 billion.3 A basic component of perioperative care bundles to reduce ...SSIs is the appropriate use of surgical antibiotic prophylaxis, including the right drug, dose, and timing of administration.4 Despite the recommendation that, for most procedures, continuation of antibiotic prophylaxis after surgery is not required, this is frequently not adhered to. In a global prevalence study in 2018, the proportion of patients receiving surgical antibiotic prophylaxis for longer than 24 h ranged from 30% to 93%.5 Prolonged antibiotic prophylaxis after surgery is associated with additional costs, an increased risk of antimicrobial resistance, and side-effects including acute kidney injury and Clostridioides difficile infection.6 In The Lancet Infectious Diseases, Stijn de Jonge and colleagues7 report the results of a systematic review and meta-analysis to reassess the effect of continuing antibiotic prophylaxis postoperatively. The authors examined whether fewer SSIs occurred with continued antibiotic prophylaxis after surgery than with its immediate discontinuation and, in a prespecified subgroup analysis, whether continued surgical antibiotic prophylaxis was of benefit when best practice standards of surgical antibiotic prophylaxis were not met.
The manufacture of mesenchymal stem/stromal cells (MSCs) for clinical use needs to be cost effective, safe and scaled up. Current methods of expansion on tissue culture plastic are labour-intensive ...and involve several 'open' procedures. We have used the closed Quantum® hollow fibre bioreactor to expand four cultures each of MSCs derived from bone marrow (BM) and, for the first time, umbilical cords (UCs) and assessed extensive characterisation profiles for each, compared to parallel cultures grown on tissue culture plastic.
Bone marrow aspirate was directly loaded into the Quantum®, and cells were harvested and characterised at passage (P) 0. Bone marrow cells were re-seeded into the Quantum®, harvested and further characterised at P1. UC-MSCs were isolated enzymatically and cultured once on tissue culture plastic, before loading cells into the Quantum®, harvesting and characterising at P1. Quantum®-derived cultures were phenotyped in terms of immunoprofile, tri-lineage differentiation, response to inflammatory stimulus and telomere length, as were parallel cultures expanded on tissue culture plastic.
Bone marrow cell harvests from the Quantum® were 23.1 ± 16.2 × 10
in 14 ± 2 days (P0) and 131 ± 84 × 10
BM-MSCs in 13 ± 1 days (P1), whereas UC-MSC harvests from the Quantum® were 168 ± 52 × 10
UC-MSCs after 7 ± 2 days (P1). Quantum®- and tissue culture plastic-expanded cultures at P1 adhered to criteria for MSCs in terms of cell surface markers, multipotency and plastic adherence, whereas the integrins, CD29, CD49c and CD51/61, were found to be elevated on Quantum®-expanded BM-MSCs. Rapid culture expansion in the Quantum® did not cause shortened telomeres when compared to cultures on tissue culture plastic. Immunomodulatory gene expression was variable between donors but showed that all MSCs upregulated indoleamine 2, 3-dioxygenase (IDO).
The results presented here demonstrate that the Quantum® can be used to expand large numbers of MSCs from bone marrow and umbilical cord tissues for next-generation large-scale manufacturing, without impacting on many of the properties that are characteristic of MSCs or potentially therapeutic. Using the Quantum®, we can obtain multiple MSC doses from a single manufacturing run to treat many patients. Together, our findings support the development of cheaper cell-based treatments.
Abstract
Purpose
While many guidelines recommend higher doses of cefazolin for patients with higher body weights, there are scant outcome data showing the benefit of higher doses. Surgical site ...infection (SSI) rates by dose of cefazolin used for surgical prophylaxis after hip or knee arthroplasty were analyzed.
Methods
Analysis of patient data entered into New Zealand’s national, prospective, surveillance and quality improvement SSI Improvement Programme database for the period July 2013 through December 2017 was conducted. The US Centers for Disease Control and Prevention’s National Healthcare Safety Network SSI definitions were used, and patients were followed for 90 days after surgery. Underdosing was defined as use of 1 g of cefazolin in patients weighing 80 kg or more or a cefazolin dose of <3 g in those weighing 120 kg or more.
Results
There were 38,288 procedures where cefazolin was used for prophylaxis; patient body weight was known for all these procedures. Of the 1,840 patients who received 1 g of cefazolin, 676 (37%) weighed 80 kg or more. Of the 2,011 patients weighing 120 kg or more, 1,464 (73%) were underdosed. After multivariable analysis, male gender, higher total surgical risk scores, performance of revision and hip arthroplasties, and cefazolin underdosing were associated with higher SSI rates. For the 2,106 underdosed patients, the odds ratio for SSI was 2.19 (95% confidence interval, 1.61-2.99; P < 0.0001). The number of higher-weight patients needed to treat to prevent 1 SSI was 83, with an estimated cost of <NZ$500 to prevent 1 infection costing an estimated NZ$40,000.
Conclusion
Patients undergoing hip or knee arthroplasty and with weights of ≥80 kg and those with weights of ≥120 kg should receive cefazolin doses of 2 g and ≥3 g, respectively, for SSI prophylaxis. The question of whether a dose of ≥4 g is needed in patients weighing 120 kg or more or who are above a given body mass index threshold (eg, >35 kg/m2 or >40 kg/m2) remains unanswered.
Our retrospective study compared genotypic antimicrobial resistance in Mycoplasma genitalium-positive specimens collected from 48 community and 33 sexual health clinic (SHC) patients. Macrolide ...resistance was similar in community (75%) and SHC (76%) patients. We observed no significant difference in fluoroquinolone resistance between community (19%) and SHC (27%) patients (p = 0.66).
Our aim was to assess national prescribing trends and determine longitudinal resistance patterns for topical antimicrobials in New Zealand. We observed a dramatic increase in fusidic acid (FA) ...resistance, and clonal expansion of FA-resistant Staphylococcus aureus. This increase was concurrent with a significant national increase in topical FA dispensing.
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