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Background: Clinical reasoning utilizing certain symptoms and scores has not proven to be a reliable decision-making tool to determine whether or not to suspect a group A Streptococcus (GAS) infection in the patient presenting with a sore throat. Culture as the so-called 'gold standard' is impracticable because it takes 1 to 2 days (and even longer in remote locations) for a result, and thus treatment decisions will be made without the result available. Rapid diagnostic antigen tests have demonstrated sufficient sensitivities and specificities in detecting GAS antigens to identify GAS throat infections., Methods: Throat swab samples were collected from patients attending the Mount Isa Hospital emergency department for a sore throat; these samples were compared to swab samples collected from healthy controls who did not have a sore throat. Both groups were aged 3-15 years. All swab samples were analyzed with a point-of-care test (Alere Test Pack +Plus with OBC Strep A). The etiologic predictive value (EPV) of the throat swab was calculated., Results: The 95% confidence interval for positive EPV was 88-100% and for negative EPV was 97-99%, depending on assumptions made., Conclusion: This study demonstrates that the point-of-care test Alere Test Pack +Plus Strep A has a high positive predictive value and is able to rule in GAS infection as long as the proportion of carriers is low. Also the negative predictive value for ruling out GAS as the etiologic agent is very high irrespective of the carrier rate. Hence, this test is always useful to rule out GAS infection., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: History, clinical examination and throat culture may be inadequate to rule in or out the presence of group A streptococci (GAS) infection in patients with sore throat in a remote location. We correlated the diagnostic accuracy for guiding antibiotic prescription of clinical decision and physiological scoring systems to a rapid diagnostic point of care (POC) test result in paediatric patients presenting with sore throat., Methods: Prospective diagnostic accuracy study conducted between 30 June 2014 and 27 February 2015 in a remote Australian ED using a convenience sample. Among paediatric patients presenting with sore throat, the Centor criteria and clinical decision were documented. Simultaneously, patients without sore throat or respiratory tract infection were tested to determine the number of carriers. A throat swab on all patients was tested using a POC test (Alere TestPack +Plus Strep A with on board control), considered as reference standard to detect GAS infection., Results: A total of 101 patients with sore throat were tested with 26 (25.7%) positive for GAS. One hundred and forty-seven patients without sore throat were tested with one positive POC test result (specificity 99%; 95% CI 96-100). Positive predictive value for clinician decision-making for a positive GAS swab (bacterial infection) was 29% (95% CI 17-43), negative predictive value 78% (95% CI 63-88). Area under ROC for the Centor score was 0.70 (95% CI 0.58-0.81)., Conclusion: Clinician judgement and Centor score are inadequate tools for clinical decision-making for children presenting with sore throat. Adjunctive POC testing provides sufficient accuracy to guide antibiotic prescription on first presentation., (© 2016 The Authors. Emergency Medicine Australasia published by John Wiley & Sons Australia, Ltd on behalf of Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.)