Thermonuclease test accuracy is preserved in methicillin-resistant isolates.

The gene encodes a thermonuclease which is present in but not in coagulase-negative staphylococci (CoNS) and is the target of the rapid phenotypic thermonuclease test. The effect of gene variation in methicillin-resistant (MRSA) on the performance of PCR testing has been noted, although there are no reports about the effect of MRSA on the activity of the thermonuclease enzyme. Our goals were to examine the sensitivity and specificity of the thermonuclease test used to distinguish from CoNS cultured from blood. In addition, we aimed to assess differences in the sensitivity, specificity and accuracy of the thermonuclease test between methicillin-sensitive (MSSA) and MRSA isolates. We performed a retrospective analysis of 1404 isolates. Each isolate from a positive blood culture was identified as a Gram-positive coccus by microscopy then analysed with the thermonuclease test (Southern Group Laboratory) prior to confirmatory identification using VITEK microbial identification platforms (bioMérieux) and cefoxitin disc diffusion testing. Of 1331 samples included in the final analysis, 189 were thermonuclease-positive, of which 176 were identified as . Of the 1142 thermonuclease-negative samples, 13 were finally identified as , giving a sensitivity of 93.1 % (95 % confidence interval [CI] 88.5-96.3) and specificity of 98.9 % (95 % CI 98.1-99.4). Of the nine proven MRSA samples, eight were thermonuclease-positive, giving a sensitivity of 88.9 % (95 % CI 51.8-99.7). Thermonuclease test accuracy for MSSA and MRSA isolates was 98.1 % (95 % CI 97.2-98.8) versus 98.8 % (95 % CI 98.0-99.3), respectively. In the era of increasing use of molecular-based microbiology assays, the thermonuclease test remains a simple, inexpensive and robust test for the presumptive identification of cultured from blood, irrespective of methicillin sensitivity

Frequency and correlates of Mycoplasma genitalium antimicrobial resistance mutations and their association with treatment outcomes: findings from a national sentinel surveillance pilot in England.

BACKGROUND Mycoplasma genitalium infection is a public health concern due to extensive antimicrobial resistance (AMR). Using data from a pilot of M. genitalium AMR surveillance, we determined the prevalence and risk factors for resistance among specimens from sexual health clinic attendees and assessed treatment outcomes. METHODS Seventeen sexual health clinics in England sent consecutive M genitalium-positive specimens to the national reference laboratory from January to March 2019. Regions of the 23S rRNA, parC and gyrA genes associated with macrolide and fluoroquinolone resistance, respectively, were amplified and sequenced where appropriate. Fisher's exact tests, univariate and multivariable logistic regression models were used to determine associations between demographic, clinical and behavioural factors and resistance-associated mutations. RESULTS Over two-thirds (173/249, 69%) of M. genitalium specimens had mutations associated with macrolide resistance, while predicted fluoroquinolone (21/251, 8%) and dual-drug (12/237, 5%) resistance were less prevalent. No specimens had both gyrA and parC resistance associated mutations. Macrolide resistance was more common in specimens from men who have sex with men (MSM) compared to heterosexual men (aOR: 2.64; 95% CI: 1.09-6.38; p = 0.03). There was an association between both macrolide and fluoroquinolone resistance and having a previous STI (p = 0.06).Only 19% of individuals returned for a test-of-cure. Of those infected with a macrolide-resistant genotype who were given azithromycin, 57/78 (73%) were known or assumed to be clinically cured; however, 43/57 (75%) of these also received doxycycline. Of the 21 with a macrolide-resistant genotype who failed treatment, 18/21 (86%) also received doxycycline. CONCLUSIONS While macrolide resistance was widespread, particularly among specimens from MSM and those with a previous STI diagnosis in the past year, resistance-associated mutations in M. genitalium did not appear to be unequivocally predictive of treatment failure

Clinical management of community-acquired meningitis in adults in the UK and Ireland in 2017: a retrospective cohort study on behalf of the National Infection Trainees Collaborative for Audit and Research (NITCAR)

Objectives To assess practice in the care of adults with suspected community-acquired bacterial meningitis in the UK and Ireland.Design Retrospective cohort study.Setting 64 UK and Irish hospitals.Participants 1471 adults with community-acquired meningitis of any aetiology in 2017.Results None of the audit standards, from the 2016 UK Joint Specialists Societies guideline on diagnosis and management of meningitis, were met in all cases. With respect to 20 of 30 assessed standards, clinical management provided for patients was in line with recommendations in less than 50% of cases. 45% of patients had blood cultures taken within an hour of admission, 0.5% had a lumbar puncture within 1 hour, 26% within 8 hours. 28% had bacterial molecular diagnostic tests on cerebrospinal fluid. Median time to first dose of antibiotics was 3.2 hours (IQR 1.3–9.2). 80% received empirical parenteral cephalosporins. 55% ≥60 years and 31% of immunocompromised patients received anti-Listeria antibiotics. 21% received steroids. Of the 1471 patients, 20% had confirmed bacterial meningitis. Among those with bacterial meningitis, pneumococcal aetiology, admission to intensive care and initial Glasgow Coma Scale Score less than 14 were associated with in-hospital mortality (adjusted OR (aOR) 2.08, 95% CI 0.96 to 4.48; aOR 4.28, 95% CI 1.81 to 10.1; aOR 2.90, 95% CI 1.26 to 6.71, respectively). Dexamethasone therapy was weakly associated with a reduction in mortality in both those with proven bacterial meningitis (aOR 0.57, 95% CI 0.28 to 1.17) and with pneumococcal meningitis (aOR 0.47, 95% CI 0.20 to 1.10).Conclusion This study demonstrates that clinical care for patients with meningitis in the UK is not in line with current evidence-based national guidelines. Diagnostics and therapeutics should be targeted for quality improvement strategies. Work should be done to improve the impact of guidelines, understand why they are not followed and, once published, ensure they translate into changed practice