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Background: Glycated haemoglobin (HbA1c) is an important outcome measure in diabetes clinical trials. For multicentre designs, HbA1c can be measured locally at participating centres or by sending blood samples to a central laboratory. This study analyses the agreement between local and central measurements, using 1-year follow-up data collected in a multicentre randomised controlled trial (RCT) of newly diagnosed children with type I diabetes. Methods: HbA1c measurements were routinely analysed both locally and centrally at baseline and then at 3, 6, 9 and 12 months and the data reported in mmol/mol. Agreement was assessed by calculating the bias and 95 % limits of agreement, using the Bland-Altman analysis method. A predetermined benchmark for clinically acceptable margin of error between measurements was subjectively set as ±10 % for HbA1c. The percentage of pairs of measurements that were classified as clinically acceptable was calculated. Descriptive statistics were used to examine the agreement within centres. Treatment group was not considered. Results: Five hundred and ninety pairs of measurement, representing 255 children and 15 trial centres across four follow-up time points, were compared. There was no significant bias: local measurements were an average of 0. 16 mmol/mol (SD = 4.5, 95 % CI -0.2 to 0.5) higher than central. The 95 % limits of agreement were -8.6 to 9. 0 mmol/mol (local minus central). Eighty percent of local measurements were within ±10 % of corresponding central measurements. Some trial centres were more varied in the differences observed between local and central measurements: IQRs ranging from 3 to 9 mmol/mol; none indicated systematic bias. Conclusions: Variation in agreement between HbA1c measurements was greater than had been expected although no overall bias was detected and standard deviations were similar. Discrepancies were present across all participating centres. These findings have implications for the comparison of standards of clinical care between centres, the design of future multicentre RCTs and existing quality assurance processes for HbA1c measurements. We recommend that centralised HbA1c measurement is preferable in the multicentre clinical trial setting. [ABSTRACT FROM AUTHOR]

Introduction: There is a paucity of data about the clinical characteristics that help identify patients at high risk of influenza infection upon ICU admission. We aimed to identify predictors of influenza infection in patients admitted to ICUs during the 2007/2008 and 2008/2009 influenza seasons and the second wave of the 2009 H1N1 influenza pandemic as well as to identify populations with increased likelihood of seasonal and pandemic 2009 influenza (pH1N1) infection. Methods: Six Toronto acute care hospitals participated in active surveillance for laboratory-confirmed influenza requiring ICU admission during periods of influenza activity from 2007 to 2009. Nasopharyngeal swabs were obtained from patients who presented to our hospitals with acute respiratory or cardiac illness or febrile illness without a clear nonrespiratory aetiology. Predictors of influenza were assessed by multivariable logistic regression analysis and the likelihood of influenza in different populations was calculated. Results: In 5,482 patients, 126 (2.3%) were found to have influenza. Admission temperature =38°C (odds ratio (OR) 4.7 for pH1N1, 2.3 for seasonal influenza) and admission diagnosis of pneumonia or respiratory infection (OR 7.3 for pH1N1, 4.2 for seasonal influenza) were independent predictors for influenza. During the peak weeks of influenza seasons, 17% of afebrile patients and 27% of febrile patients with pneumonia or respiratory infection had influenza. During the second wave of the 2009 pandemic, 26% of afebrile patients and 70% of febrile patients with pneumonia or respiratory infection had influenza. Conclusions: The findings of our study may assist clinicians in decision making regarding optimal management of adult patients admitted to ICUs during future influenza seasons. Influenza testing, empiric antiviral therapy and empiric infection control precautions should be considered in those patients who are admitted during influenza season with a diagnosis of pneumonia or respiratory infection and are either febrile or admitted during weeks of peak influenza activity. [ABSTRACT FROM AUTHOR]

The Seeplex™ TB Detection-2 assay (Rockville, MD) is a nested endpoint PCR for the Mycobacterium tuberculosis complex (MTBC) targets IS6110 and MPB64 that utilizes dual priming oligonucleotide technology. When used to detect the presence of MTBC DNA in formalin-fixed paraffin-embedded tissue specimens, the sensitivity and specificity of this assay is equivalent to a labor-intensive traditional endpoint PCR assay and is more sensitive than a commercial real-time PCR assay. [ABSTRACT FROM AUTHOR]

The increase in adamantine resistance in influenza A (H3N2) and the emergence of oseltamivir resistance in influenza A (H1N1) has necessitated the use of rapid methodologies to detect influenza subtype. The purpose of this study was to evaluate the CombiMatrix influenza detection system compared to the FDA approved Luminex Respiratory virus panel (RVP) assay for influenza A subtyping. Verification of the CombiMatrix influenza detection system was carried out using the Luminex RVP assay as a reference method. A limit of detection (LOD) series was performed using the Luminex and CombiMatrix systems with both influenza A H3N2 and H1N1 viruses. Seventyfive clinical specimens were used in the study. Of these, 16 were influenza A (H3N2) positive and five were influenza A (H1N1) positive. Fifty-four specimens were influenza A negative or "no call" (inconclusive) or could not be subtyped. The LOD of the Luminex RVP assay was found to be 0.3 TCID50s/mL for influenza A (H3N2) and 16 TCID50s/mL for influenza A (H1N1). The LOD of the CombiMatrix influenza detection system was 200 TCID50s/mL for influenza A (H3N2) and 16 000 TCID50s/mL for influenza A (H1N1). The sensitivity of the CombiMatrix influenza detection system was 95.2% and the specificity was 100%. The CombiMatrix influenza detection system is an effective methodology for influenza A subtype analysis, specifically in laboratories with a constrained budget or limited molecular capabilities. [ABSTRACT FROM AUTHOR]

This study describes the prevalence of culture-positive adenovirus serotypes in culture-positive respiratory specimens sent to the Central Public Health Laboratory, Toronto, Ontario, Canada for the period September 2007-June 2008. Total nucleic acid was extracted from virus cultures using an automated extraction method followed by polymerase chain reaction and Sanger sequencing of the adenovirus hexon gene hypervariable region 7. 73% of specimens (n = 70) were from patients ⩽ 4 years of age. Of the 96 adenovirus isolates, the most common identified serotypes were serotype 3 (n = 44, 46%), serotype 2 (n = 25, 26%), serotype 1 (n = 17, 18%), and serotype 21 (n = 5, 5%). Adenovirus serotype 14 was not found in this study group. The leading serotype, Ad3, was identified throughout the duration of the study period. Molecular methods allow for the determination of circulating adenovirus serotypes and be used to document the spread of highly virulent adenoviral serotypes into a region. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Measurement of HbA1c in multicentre diabetes trials – should blood samples be tested locally or sent to a central laboratory: an agreement analysis" which appeared in the previous issue.