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<b>Background and Objectives:</b> A new test (Dr. KSU H1N1 RT-PCR kit) was recently developed to provide a less expensive alternative to real-time reverse transcriptase-polymerase chain reaction (RT-PCR). We report the findings of a validation study designed to assess the diagnostic accuracy, including sensitivity and specificity, of the new kit, as compared to real-time RT-PCR. <b>Design and Setting:</b> Cross-sectional validation study conducted from 18-22 November 2009 at a primary care clinic for H1N1 at a tertiary care teaching hospital in Riyadh. <b>Patients and Methods:</b> Nasopharyngeal swab samples and data on socio-demographic characteristics and symptoms were collected from 186 patients. Swab samples were sent to the laboratory for testing with both real-time RT-PCR and the new Dr. KSU H1N1 RT-PCR kit. We measured the sensitivity and specificity of the new test across the entire sample size and investigated how these values were affected by patient socio-demographic characteristics and symptoms. <b>Results</b>: The outcomes of the two tests were highly correlated (kappa=0.85; <i>P</i>&lt;.0001). The sensitivity and specificity of the new test were 99.11&#x0025; and 83.78&#x0025;, respectively. The sensitivity of the new test was affected only minimally (96&#x0025;-100&#x0025;) by patient characteristics and number of symptoms. On the other hand, the specificity of the new test varied depending on how soon patients were tested after onset of symptoms (100&#x0025; specificity when swabs were taken on the first day of the symptoms, decreasing to 75&#x0025; when swabs were taken on or after the third day). The specificity of the new test also increased with increasing body temperature. <b>Conclusion:</b> The new test seems to provide a cost-effective alternative to real-time RT-PCR for diagnosing H1N1 influenza. However, further testing may be needed to verify the efficacy of the test in different settings and communities.