Descriptive analysis of targeted carbapenemase genes and antibiotic susceptibility profiles among carbapenem-resistant Acinetobacter baumannii tested in the Antimicrobial Resistance Laboratory Network-United States, 2017-2020

Acinetobacter baumannii is a Gram-negative bacillus that can cause severe and difficult-to-treat healthcare-associated infections. A. baumannii can harbor mobile genetic elements carrying genes that produce carbapenemase enzymes, further limiting therapeutic options for infections. In the United States, the Antimicrobial Resistance Laboratory Network (AR Lab Network) conducts sentinel surveillance of carbapenem-resistant Acinetobacter baumannii (CRAB). Participating clinical laboratories sent CRAB isolates to the AR Lab Network for characterization, including antimicrobial susceptibility testing and molecular detection of class A (Klebsiella pneumoniae carbapenemase), class B (Active-on-Imipenem, New Delhi metallo-β-lactamase, and Verona integron-encoded metallo-β-lactamase), and class D (Oxacillinase, blaOXA-23-like, blaOXA-24/40-like, blaOXA-48-like, and blaOXA-58-like) carbapenemase genes. During 2017‒2020, 6,026 CRAB isolates from 45 states were tested for targeted carbapenemase genes; 1% (64 of 5,481) of CRAB tested for targeted class A and class B genes were positive, but 83% (3,351 of 4,041) of CRAB tested for targeted class D genes were positive. The number of CRAB isolates carrying a class A or B gene increased from 2 of 312 (<1%) tested in 2017 to 26 of 1,708 (2%) tested in 2020. Eighty-three percent (2,355 of 2,846) of CRAB with at least one of the targeted carbapenemase genes and 54% (271 of 500) of CRAB without were categorized as extensively drug resistant; 95% (42 of 44) of isolates carrying more than one targeted gene had difficult-to-treat susceptibility profiles. CRAB isolates carrying targeted carbapenemase genes present an emerging public health threat in the United States, and their rapid detection is crucial to improving patient safety.IMPORTANCEThe Centers for Disease Control and Prevention has classified CRAB as an urgent public health threat. In this paper, we used a collection of >6,000 contemporary clinical isolates to evaluate the phenotypic and genotypic properties of CRAB detected in the United States. We describe the frequency of specific carbapenemase genes detected, antimicrobial susceptibility profiles, and the distribution of CRAB isolates categorized as multidrug resistant, extensively drug-resistant, or difficult to treat. We further discuss the proportion of isolates showing susceptibility to Food and Drug Administration-approved agents. Of note, 84% of CRAB tested harbored at least one class A, B, or D carbapenemase genes targeted for detection and 83% of these carbapenemase gene-positive CRAB were categorized as extensively drug resistant. Fifty-four percent of CRAB isolates without any of these carbapenemase genes detected were still extensively drug-resistant, indicating that infections caused by CRAB are highly resistant and pose a significant risk to patient safety regardless of the presence of one of these carbapenemase genes.

Antimicrobial Resistance Laboratory Network's multisite evaluation of the ThermoFisher Sensititre GN7F broth microdilution panel for antimicrobial susceptibility testing

In 2017, the Centers for Disease Control and Prevention (CDC) established the Antimicrobial Resistance Laboratory Network to improve domestic detection of multidrug-resistant organisms. CDC and four laboratories evaluated a commercial broth microdilution panel. Antimicrobial susceptibility testing using the Sensititre GN7F (ThermoFisher Scientific, Lenexa, KS) was evaluated by testing 100 CDC and Food and Drug Administration AR Isolate Bank isolates [40 Enterobacterales (ENT), 30 Pseudomonas aeruginosa (PSA), and 30 Acinetobacter baumannii (ACB)]. We assessed multiple amounts of transfer volume (TV) between the inoculum and tubed 11-mL cation-adjusted Mueller-Hinton broth: 1 µL [tribe Proteeae (P-tribe) only] and 10, 30, and 50 µL, resulting in respective CFU per milliter of 1 × 104, 1 × 105, 3 × 105, and 5 × 105. Four TV combinations were analyzed: standard (STD) [1 µL (P-tribe) and 10 µL], enhanced standard (E-STD) [1 µL (P-tribe) and 30 µL], 30 µL, and 50 µL. Essential agreement (EA), categorical agreement, major error (ME), and very major error (VME) were analyzed by organism then TVs. For ENT, the average EA across laboratories was <90% for 7 of 15 β-lactams using STD and E-STD TVs. As TVs increased, EA increased (>90%), and VMEs decreased. For PSA, EA improved as TVs increased; however, MEs also increased. For ACB, increased TVs provided slight EA improvements; all TVs yielded multiple VMEs and MEs. For ENT and ACB, Minimum inhibitory concentrations (MICs) trended downward using a 1 or 10 µL TV; there were no obvious MIC trends by TV for PSA. The public health and clinical consequences of missing resistance warrant increased TV of 30 µL for the GN7F, particularly for P-tribe, despite being considered "off-label" use.

535 Private Trauma Lists: A Pragmatic Panacea During This Pandemic

Introduction

COVID-19 has disrupted the efficiency of hospitals nationwide. Ambulant trauma surgery was minimised to reduce risk of contracting COVID-19. Operating capacity significantly reduced and surgical training dramatically curtailed. Locally, a private hospital has been utilised as a green site with consultant-lead trauma lists. Our aim is to review the safety and efficiency of this service.

Method

Patients underwent pre-assessment, COVID-19 swabs and 7 days isolation pre and post-op. Staff also underwent swabbing. Prospectively data was gathered for all patients operated on at this site from 12/05/2020 to 20/08/2020. Records reviewed for readmission, complications and COVID status. A satisfaction questionnaire was sent to trainees who operated at this site.

Results

79 operations were completed during this period. 50 male and 29 female, average age 49, average ASA 2. No complications or COVID-19 infections were recorded. Mean time to theatre was 18 days. Delays to theatre led to 2 complications. 87% of trainees felt training was maintained.

Conclusions

Establishing a green site enabled efficient and safe management whilst still facilitating surgical training. This requires clear guidelines for staff and patients. We believe this model can help trauma service provision as the pandemic evolves.

Achilles tendon rupture: what you need to know

Heel pain and a history of a 'pop' or feeling 'something go' are the buzz phrases classically associated with Achilles tendon rupture. However, the diagnosis is often missed in clinical practice because of the assumption that this is a sporting injury suffered only by the young or middle-aged. In a sedentary older patient, the injury may be dismissed as an ankle sprain. If swelling is present but no injury is recalled then deep vein thrombosis is suspected, but Achilles rupture is not. The diagnosis of Achilles tendon rupture is clinical, based on history and examination. Radiological imaging (ultrasound scan) is useful to plan orthopaedic management and exclude concomitant deep vein thrombosis. In most cases, non-operative management with the ankle held plantar flexed in a boot is the current best practice.

Deconditioned Knee: The Effectiveness of a Rehabilitation Program that Restores Normal Knee Motion to Improve Symptoms and Function

BACKGROUND

Knee pain can cause a deconditioned knee. Deconditioned is defined as causing one to lose physical fitness. Therefore, a deconditioned knee is defined as a painful syndrome caused by anatomical or functional abnormalities that result in a knee flexion contracture (functional loss of knee extension), decreased strength, and decreased function. To date, no published studies exist examining treatment for a deconditioned knee.

OBJECTIVE

To determine the effectiveness of a rehabilitation program focused on increasing range of motion for patients with a deconditioned knee.

METHODS

Fifty patients (mean age 53.2 years) enrolled in the study. Objective evaluation included radiographs, knee range of motion, and isokinetic strength testing. The International Knee Documentation Committee (IKDC) subjective questionnaire was used to measure symptoms and function. Patients were given a rehabilitation program to increase knee extension (including hyperextension) and flexion equal to the normal knee, after which patients were instructed in leg strengthening exercises.

RESULTS

Knee extension significantly improved from a mean deficit of 10° to 3° and knee flexion significantly improved from a mean deficit of 19° to 9°. The IKDC survey scores significantly improved from a mean of 34.5 points to 70.5 points 1 year after beginning treatment. The IKDC subjective pain frequency and severity scores were significantly improved.

CONCLUSIONS

A rehabilitation program that improves knee range of motion can relieve pain and improve function for patients with a deconditioned knee.

Can the uptake of breast screening by Asian women be increased? A randomized controlled trial of a linkworker intervention

This study investigates the effectiveness of a linkworker intervention, giving encouragement and explanations about breast screening, on the subsequent attendance for screening by 'Asian' women. The control group received no visits. The study population comprised all women with Asian names, from a batch of general practices where high proportions of patients were Asian, who were invited for screening. It was found that 59 per cent of the intervention group could be contacted by linkworkers. No difference in attendance was found between the intervention and control groups (49 per cent and 47 per cent). Twenty-five per cent of women were permanently or temporarily not resident at the invitation address. Attendance for screening was related to length of stay in the United Kingdom. This type of intervention was not a successful strategy for promoting uptake by Asian women, and indicates that it is essential to evaluate rigorously projects with such objectives.