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AimsThe duration of systemic antibiotic treatment following first-stage revision surgery for periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is contentious. Our philosophy is to perform an aggressive debridement, and to use a high local concentration of targeted antibiotics in cement beads and systemic prophylactic antibiotics alone. The aim of this study was to assess the success of this philosophy in the management of PJI of the hip using our two-stage protocol.MethodsThe study involved a retrospective review of our prospectively collected database from which we identified all patients who underwent an intended two-stage revision for PJI of the hip. All patients had a diagnosis of PJI according to the major criteria of the Musculoskeletal Infection Society (MSIS) 2013, a minimum five-year follow-up, and were assessed using the MSIS working group outcome-reporting tool. The outcomes were grouped into ‘successful’ or ‘unsuccessful’.ResultsA total of 299 two-stage revision THAs in 289 patients met the inclusion criteria, of whom 258 (86%) proceeded to second-stage surgery. Their mean age was 68.1 years (28 to 92). The median follow-up was 10.7 years (interquartile range (IQR) 6.3 to 15.0). A 91% success rate was seen in those patients who underwent reimplantation, decreasing to 86% when including those who did not proceed to reimplantation. The median duration of postoperative systemic antibiotics following the first stage was five days (IQR 5 to 9). There was no significant difference in outcome between those patients who were treated with antibiotics for ≤ 48 hours (p = 0.961) or ≤ five days (p = 0.376) compared with those who were treated with longer courses. Greater success rates were seen for Gram-positive PJIs (87%) than for Gram-negative (84%) and mixed-Gram PJIs (72%; p = 0.098).ConclusionAggressive surgical debridement with a high local concentration of targeted antibiotics at the time of first-stage revision surgery for PJI of the hip, without prolonged systemic antibiotics, provides a high rate of success, responsible antibiotic stewardship, and reduced hospital costs.Cite this article: Bone Joint J 2023;105-B(5):511–517.

The SARS-CoV-2 lineage B.1.1.7, designated variant of concern (VOC) 202012/01 by Public Health England1, was first identified in the UK in late summer to early autumn 20202. Whole-genome SARS-CoV-2 sequence data collected from community-based diagnostic testing for COVID-19 show an extremely rapid expansion of the B.1.1.7 lineage during autumn 2020, suggesting that it has a selective advantage. Here we show that changes in VOC frequency inferred from genetic data correspond closely to changes inferred by S gene target failures (SGTF) in community-based diagnostic PCR testing. Analysis of trends in SGTF and non-SGTF case numbers in local areas across England shows that B.1.1.7 has higher transmissibility than non-VOC lineages, even if it has a different latent period or generation time. The SGTF data indicate a transient shift in the age composition of reported cases, with cases of B.1.1.7 including a larger share of under 20-year-olds than non-VOC cases. We estimated time-varying reproduction numbers for B.1.1.7 and co-circulating lineages using SGTF and genomic data. The best-supported models did not indicate a substantial difference in VOC transmissibility among different age groups, but all analyses agreed that B.1.1.7 has a substantial transmission advantage over other lineages, with a 50% to 100% higher reproduction number.

Fungal infection exacts a severe burden on patients with acute leukaemia. Azole prophylaxis attempts to mitigate this impact but is associated with toxicity and cost as well as the potential to select for resistance. The development of biomarkers including galactomannan and β-1,3-d-glucan may improve detection of early disease and thus reduce the need for prophylaxis, though these assays also have their limitations. In this debate, Howard et al. argue in favour of continuing chemoprophylaxis in patients with acute leukaemia receiving systemic chemotherapy, citing the multiple randomized control trials and meta-analyses that demonstrate its efficacy. Taynton et al. argue that fungal biomarker surveillance in the absence of primary antifungal chemoprophylaxis is a safe alternative that could reduce antifungal use and the development of resistance.

IntroductionViral sequencing of SARS-CoV-2 has been used for outbreak investigation, but there is limited evidence supporting routine use for infection prevention and control (IPC) within hospital settings.MethodsWe conducted a prospective non-randomised trial of sequencing at 14 acute UK hospital trusts. Sites each had a 4-week baseline data-collection period, followed by intervention periods comprising 8 weeks of ‘rapid’ (ResultsA total of 2170 HOCI cases were recorded from October 2020-April 2021, with sequence reports returned for 650/1320 (49.2%) during intervention phases. We did not detect a statistically significant change in weekly incidence of HAIs in longer-turnaround (IRR 1.60, 95%CI 0.85-3.01; P=0.14) or rapid (0.85, 0.48-1.50; P=0.54) intervention phases compared to baseline phase. However, IPC practice was changed in 7.8% and 7.4% of all HOCI cases in rapid and longer-turnaround phases, respectively, and 17.2% and 11.6% of cases where the report was returned. In a per-protocol sensitivity analysis there was an impact on IPC actions in 20.7% of HOCI cases when the SRT report was returned within 5 days.ConclusionWhile we did not demonstrate a direct impact of sequencing on the incidence of nosocomial transmission, our results suggest that sequencing can inform IPC response to HOCIs, particularly when returned within 5 days.

The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021., A study of the evolution of the SARS-CoV-2 virus in England between September 2020 and June 2021 finds that interventions capable of containing previous variants were insufficient to stop the more transmissible Alpha and Delta variants.

We report on the origins, development and refinement of an online inventory to help cooperating teachers focus on selected dimensions of their practice. The Mentoring Profile Inventory (MPI) helps quantify important features of both the motivating and challenging aspects of mentoring student teachers and provides results to respondents in a graphic, easy-to-understand and immediate feedback report (14 sub-scales and 3 summary charts). Psychometric properties of the MPI are shown to be robust. Results can be used individually or collectively to facilitate cooperating teacher professional development by providing the opportunity for dialog around a set of common issues.

Our group first reported the operation of a relativistic backward wave oscillator (BWO) in the so-called “cross-excitation” regime in 1998. This instability, whose general properties were predicted earlier through numerical studies, was a consequence of using a particularly shallow rippled-wall waveguide (slow wave structure – SWS) that was installed in the experiment to diagnose pulse shortening in a long pulse electron beam-driven high power microwave (HPM) source. This particular SWS was required to accommodate laser interferometry measurements during the course of microwave generation. Since those early experiments we have further studied this regime in greater detail using two different SWS lengths. We have invoked time-frequency analysis, the smoothed-pseudo Wigner-Ville distribution in particular, to interpret the heterodyned signals of the radiated power measurements. These recent results are consistent with earlier theoretical predictions for the onset, voltage scaling, and general behavior for this instability. This paper presents data for a relativistic BWO operating in the single frequency regime for two axial modes, operating in the cross-excitation regime, and discusses the interpretation of the data, as well as the methodology used for its analysis. Although operation in the cross-excitation regime is typically avoided due to its poorer efficiency, we discuss how it may be exploited in HPM effects studies.

A completely automated apparatus for the quantitative analysis of volatile compounds in urine vapor and breath is described in detail. More than two-hundred compounds are shown to be routinely measured in urine vapor, and the application of the apparatus to orthomolecular diagnosis is discussed.

Autosomal dominant olivopontocerebellar degeneration was evaluated in a family numbering 414 living members. Urine samples were obtained from 5 affected and 5 unaffected not at-risk family members after 4 days on a synthetic diet. 159 urine vapor constituents were measured by gas-liquid and ion-exchange chromatography and a non-correlation index was calculated. 2 distinct populations of urine vapor patterns were identified which conformed to the normal and disease affected groups, thus a diagnostically useful pattern for this disease in this family has been demonstrated which will be helpful in genetic counselling and potential elimination of the disease.

Since we are using the gas chromatography of volatile urine constituents in a procedure to diagnose diseases, we wished to identify the components of our sample. Forty-two compounds were identified by gas chromatography—mass spectroscopy, using a modified head-space collection technique. A co-injection procedure was used to place these components on a chromatogram from our disease diagnosis instrument.