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Despite the importance of antimicrobial susceptibility testing (AST) to clinical management of infection and to antimicrobial resistance (AMR) surveillance, methodologies and breakpoints of the two most commonly used systems worldwide, CLSI and EUCAST, are far from harmonized. Most laboratories in resource-constrained settings such as Southeast Asia, including our own, currently follow CLSI disk diffusion AST guidelines. Many aspects of the EUCAST system, not least the freely available nature of all output, are likely to be attractive to laboratories in our setting, but published reports of the practical differences between CLSI and EUCAST methodologies are lacking. Our manuscript highlights key differences between CLSI and EUCAST disk diffusion AST methodologies, and the practical implications of adopting EUCAST guidelines in our laboratory network. We discuss potential barriers to adoption of EUCAST guidelines in resource-Clinical Microbiology and Infection constrained settings including difficulties in obtaining horse blood for media supplementation and the need for an MIC method for AST of N. gonorrhoeae. We highlight the need for a globally harmonized AST system that is practical and freely available, and we hope this commentary will be useful for laboratories considering switching between CLSI and EUCAST.

Background Melioidosis is difficult to diagnose clinically and culture of Burkholderia pseudomallei is the current, imperfect gold standard. However, a reliable point-of-care test (POCT) could enable earlier treatment and improve outcomes. Methods We evaluated the sensitivity and specificity of the Active Melioidosis Detect™ (AMD) rapid test as a POCT and determined how much it reduced the time to diagnosis compared with culture. Results We tested 106 whole blood, plasma and buffy coat samples, 96 urine, 28 sputum and 20 pus samples from 112 patients, of whom 26 (23.2%) were culture-positive for B. pseudomallei. AMD sensitivity and specificity were 65.4 and 87.2%, respectively, the latter related to 10 weak positive reactions on urine samples, considered likely false positives. The positive predictive value was 60.7%, negative predictive value was 89.3% and concordance rate between operators reading the test was 95.7%; time to diagnosis decreased by a median of 23 h. Conclusions Our findings confirm that a strongly positive AMD result can reduce the time to diagnosis of melioidosis. However, the AMD currently has a disappointing overall sensitivity, especially with blood fractions, and specificity problems when testing urine samples.

David AB Dance,1 Vanaporn Wuthiekanun,2 Derek Sarovich,3 Erin P Price,3 Direk Limmathurotsakul,4 Bart J Currie,5 Trinh Thanh Trung61Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Vientiane, Lao PDR; 2Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand; 3University of the Sunshine Coast, Sippy Downs, QLD, Australia; 4Microbiology, Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand; 5Infectious Diseases, Menzies School of Health Research, Darwin, NT, Australia; 6Vietnam National University, Hanoi, VietnamWe are writing, on behalf of the International Melioidosis Society Committee, as agroup of researchers and clinicians with longstanding experience of melioidosis andBurkholderia pseudomallei as we have some concerns about the above paper thatwas published in your journal recently.1Although we believe that melioidosis is undoubtedly being under-diagnosed inIndonesia,2,3 we are not convinced that the isolate in this case is B.pseudomalleibased on the information provided by the authors. Although it is difficult to becertain from the photographs in Figure 2, the colonies do not appear typical of thespecies to the microbiologists amongst us, who have seen several thousand isolates of B.pseudomallei over the past 30 years. Furthermore, the authors do not reportwhether the isolate was oxidase positive or negative. We believe that more comprehensivemethods of confirming the identity, particularly genomic analysis,should have been undertaken before publishing the case.4 Unfortunately, the postamplification16s analysis described in the paper might not have been able todistinguish between B.pseudomallei and other Burkholderia species (particularlyB.thailandensis and several as-yet-uncharacterized Burkholderia spp.), and we would have recommended additional testing, for example, multilocus sequencetyping and PCR for the TTS1 gene at least. View the original paper by Nuryastuti and colleagues.

International audience; Human respiratory syncytial virus (HRSV) is one of the most important causes of acute respiratory infections (ARI) in young children. HRSV diagnosis is based on the detection of the virus in respiratory specimens. Nasopharyngeal swabbing is considered the preferred method of sampling, although there is limited evidence of the superiority of nasopharyngeal swabs (NPS) over the less invasive nasal (NS) and throat (TS) swabs for virus detection by real-time reverse transcription quantitative polymerase chain reaction (RT-qPCR). In the current study, we compared the three swabbing methods for the detection of HRSV by RT-qPCR in children hospitalized with ARI at Mahosot Hospital, Vientiane, Laos. In 2014, NS, NPS, and TS were collected from 288 children. All three samples were tested for HRSV by RT-qPCR; 141 patients were found positive for at least one sample. Almost perfect agreements (κ > 0.8) between the swabs, compared two by two, were observed. Detection rates for the three swabs (between 93% and 95%) were not significantly different, regardless of the clinical presentation. Our findings suggest that the uncomfortable and technically more demanding NPS method is not mandatory for HRSV detection by RT-qPCR.

Background Pneumococcal disease is an important cause of childhood morbidity and mortality worldwide. Evidence is required to support the introduction of pneumococcal conjugate vaccines (PCVs) in low-income and middle-income countries (LMICs). PCVs prevent disease through both direct protection of vaccinated individuals, and indirect protection of unvaccinated people via reduction of nasopharyngeal carriage and transmission of vaccine-type (VT) pneumococci. We aimed to determine the degree of this indirect effect after introduction of 13-valent PCV (PCV13) at three sites in Asia-Pacific, and describe the relationship between PCV coverage and indirect protection. Methods We are recruiting and swabbing children aged 2–59 months, admitted to participating hospitals with acute respiratory tract infections in Laos, Mongolia, and Papua New Guinea. Pneumococci are detected using lytA qPCR and serotyped by microarray. We are comparing risk of VT carriage in undervaccinated cases by village/subdistrict-level PCV13 coverage in children younger than 5 years. Individual PCV status is determined using written records and village PCV coverage is determined by administrative data or survey. Recruitment is due to finish in March, 2019. Findings As of June, 2018, we have recruited 1208, 1056, and 897 cases, and tested 1099, 624, and 405 samples, from Laos, Mongolia, and Papua New Guinea, respectively. Overall, pneumococcal carriage varied from 37% in Laos to 88% in Papua New Guinea. In Laos, VT carriage decreased from 18% to 6% from the first to the third year post-PCV. In Papua New Guinea, VT carriage decreased from 54% to 37% from the first to the third year after PCV introduction. In Mongolia, VT carriage decreased from 31% pre-PCV to 24% in the first year after PCV. Undervaccinated children from villages with less than 50% coverage are 1·08 (95% CI 0·69–1·79) and 1·44 (95% CI 0·99–2·10) times more likely to be carrying VT than those from villages with 50% or more coverage, among the 336 in Laos and 83 children in Papua New Guinea, respectively, for whom we have both PCV and carriage data. This difference does not reach statistical significance. Interpretation In the absence of feasible methods for pneumococcal disease surveillance in LMICs, studies of nasopharyngeal carriage of VT pneumococci, which is a prerequisite for disease, provide useful information to guide vaccine policy. The inclusion of three sites, which have contrasting vaccine schedules and pneumococcal epidemiology, enable us to explore factors that could maximise indirect protection from PCVs. Funding Bill & Melinda Gates Foundation, Gavi the Vaccine Alliance.

A test phantom, including a wide range of mammographic tissue equivalent materials and test details, was imaged on a digital mammographic system. In order to quantify the effect of scatter on the contrast obtained for the test details, calculations of the scatter-to-primary ratio (S/P) have been made using a Monte Carlo simulation of the digital mammographic imaging chain, grid and test phantom. The results show that the S/P values corresponding to the imaging conditions used were in the range 0.084-0.126. Calculated and measured pixel values in different regions of the image were compared as a validation of the model and showed excellent agreement. The results indicate the potential of Monte Carlo methods in the image quality-patient dose process optimisation, especially in the assessment of imaging conditions not available on standard mammographic units

‘The opportunities of a pathologist at a large Eastern Hospital are many; but his time for research work is short, and his conveniences are few.’ So begins this landmark paper written by Alfred Whitmore and published in the journal in 1913 [1]. He goes on to demonstrate just how well that short time can be used by someone with the energy, intelligence and scientific rigour in order to make the most of those opportunities. I first read this paper 15 years ago and have re-read it many times since, usually reflecting on how remarkably little our knowledge of melioidosis has advanced since 1913. I notice something new each time I read it and, most importantly of all, each time it is an absolute pleasure to read. How many modern scientific papers leave one feeling the same way?

Melioidosis is an infectious disease endemic to northern Australia and Southeast Asia. In response to clinical confusion regarding the appropriate dose of amoxicillin-clavulanate, we have developed guidelines for the appropriate dosing of this second-line agent. For eradication therapy for melioidosis, we recommend 20/5 mg/kg orally, three times daily. Copyright © 2008 by The American Society of Tropical Medicine and Hygiene.

OBJECTIVE: To study the incidence, natural history and symptomatic effects of bacteriuria after urodynamic studies in women. PATIENTS AND METHODS: In a prospective study in the urogynaecology clinic of a large District General Hospital, 214 women (mean age 52.3 years, range 23-81) underwent urodynamic studies. Bacteriuria was detected by semiquantitative culture at 2 and 7 days after the test. Women completed a 7-day diary of symptoms and events. RESULTS: The incidence of bacteriuria after urodynamic studies was 7.9%. Bacteriuria was transient in four of 17 women but persisted in nine and developed late in four; only one of 17 infections gave rise to symptoms. Irritative bladder symptoms after the test occurred in 34% of women, but only three went to their doctors because of concern about a possible urinary tract infection. Advancing age was the only variable associated with bacteriuria after urodynamic studies (P= 0.05). Menopausal status, past history of urinary tract infection, number of urethral instrumentations required, order number in a session, peak urinary flow rate and urodynamic diagnosis were not associated variables. CONCLUSIONS: In a large series of women presenting to a urogynaecology clinic, urodynamic investigations were associated with a high incidence of transient irritative symptoms but a low incidence of bacteriuria (8%). Infection was asymptomatic in most patients, but its natural history was unpredictable. Transient, persistent and late cases of bacteriuria all occurred. In this population, urodynamic studies are associated with a low level of morbidity.

Burkholderia pseudomallei causes melioidosis, a serious and often fatal bacterial infection. B. pseudomallei can behave as a facultatively intracellular organism and this ability may be important in the pathogenesis of both acute and chronic infection. The uptake of B. pseudomallei and other Burkholderia spp. by cells in tissue culture was examined by electron microscopy. B. pseudomallei can invade cultured cell lines including phagocytic lines such as RAW264, J774 and U937, and non-phagocytic lines such as CaCO-2, Hep2, HeLa, L929, McCoy, Vero and CHO. Uptake was followed by the intracellular multiplication of B. pseudomallei and the induction of cell fusion and multinucleate giant cell formation. Similar effects were produced by B. mallei and B. thailandensis.

This work compares the detection of microcalcification clusters (MC) in digital mammography images with different image quality levels.