Multicenter Clinical Evaluation of the Automated Aries Group A Strep PCR Assay from Throat Swabs.

Group A Streptococcus (GAS) is one of the leading causes of bacterial pharyngitis. Early GAS diagnosis is critical for appropriate antibiotic administration that reduces the risk of GAS sequelae and limits spread of the infection. The Aries Group A Strep (GAS) assay (Luminex, Austin, TX) is a fully automated PCR assay for direct detection of GAS in throat swab specimens in less than 2 h with minimum hands-on time. This multicenter prospective study evaluated the clinical performance of the Aries GAS assay compared to that of Streptococcus pyogenes culture. Subjects with symptoms consistent with pharyngitis were enrolled across four sites in the United States, and a throat swab in liquid Amies medium was obtained. Aries and reference testing was performed within 72 and 48 h after sample collection, respectively. Of 623 throat swab specimens from patients with pharyngitis (93.6% <18 years old, 54.3% female), the reference method yielded valid results for 618 specimens. Reference and Aries assay testing showed GAS-positive results for 160 (25.9%) and 166 (26.9%) specimens, respectively. Compared to the reference method, Aries assay sensitivity was 97.5% (95% confidence interval [CI], 93.7% to 99.0%), specificity was 97.8% (95% CI, 96.0 to 98.8%), positive predictive value was 94.0% (95% CI, 89.3% to 96.7%), and negative predictive value was 99.1% (95% CI, 97.7% to 99.7%). There were 10 false-positive and four false-negative detections with the Aries assay. Discrepant analysis with bidirectional sequencing yielded concordant results with the Aries assay for nine of 14 discordant samples. The Aries assay had high sensitivity and specificity for qualitative detection of group A Streptococcus from patients with pharyngitis.

Preventing glycaemic relapse in recently controlled type 2 diabetes patients: a randomised controlled trial.

AIMS/HYPOTHESIS: After achieving glycaemic control, many type 2 diabetic patients relapse to clinically significant levels of hyperglycaemia. We sought to determine the optimal frequency of telephone contact by nurse practitioners that was necessary to prevent glycaemic relapse. METHODS: This parallel, randomised controlled trial ran from June 2002 to February 2006 at an academic medical centre, studying 164 type 2 diabetic patients who had recently achieved glycaemic control. Participants were randomly assigned by sequential, concealed, computer-generated allocation to a 2 year maintenance strategy consisting of: (1) routine follow-up (n = 54); (2) routine follow-up and quarterly telephone contact (n = 55); or (3) routine follow-up and monthly telephone contact (n = 55). Blinding was not possible. The primary outcome was cumulative incidence of glycaemic relapse, defined as an increase in HbA(1c) of > or =1%; all participants were analysed. Cumulative incidence and prevalent proportions were compared. Weight change and hypoglycaemia were also assessed. RESULTS: All participants randomised were included in the analyses. The study was completed by 90% of participants and intervention fidelity was high. At 24 months, the cumulative incidence of relapse was 41%. At 12 months, prevalent proportions of relapse were 20%, 14% and 15% for control, quarterly contact and monthly contact, respectively. At 24 months, they were 25%, 21% and 29%, respectively. There was no statistically significant difference in cumulative incidence or prevalent proportions of relapse among the study arms. Adverse events did not differ between study arms. CONCLUSIONS/INTERPRETATION: This first randomised controlled trial to test an intervention to prevent glycaemic relapse found that regularly scheduled telephone contact by a nurse practitioner was no more effective than routine follow-up care in preventing glycaemic relapse.