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Objective To compare the diagnostic performance of three rapid antigen detection tests (RADTs) for group A Streptococcus (GAS). Design A hospital-based, cross-sectional, retrospective study. Setting A comparative study of rapid diagnostic tests for GAS using clinical specimens in a single institute. Participants 225 children in the outpatient clinics ofKorea University Guro Hospitalwith suspicious symptoms were subjected to throat swab sampling. A dual-swab applicator was used. Samples were stored at below −70°C in a 10 mL transport tube containing 1 mL liquid Stuart’s transport medium. Outcome measures All tests were performed in the laboratory by trained clinical laboratory scientists. Sensitivity, specificity, accuracy and kappa index of three RADTs were compared with the reference PCR test and culture results. Results Of the 225 patients suspected of having GAS, 67 and 90 were positive for GAS in the culture and PCR tests, respectively. Compared with the reference culture, the sensitivity for GAS was 92.5% (CI 83.4 to 97.5), 71.6% (CI 59.3 to 81.9) and 74.63% (CI 62.5 to 84.4) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 97.0% (CI 93.1 to 99.0), 94.6% (CI 90.1 to 97.5) and 92.9% (CI 87.8 to 96.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively. Compared with the reference GAS real-time PCR, the sensitivity was 73.3% (CI 62.9 to 82.1), 63.3% (CI 52.5 to 73.2) and 67.8% (CI 57.1 to 77.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 99.3% (CI 95.9 to 99.9), 100.0% (CI 97.3 to 100.0) and 99.3% (CI 95.9 to 99.9) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively. Conclusions The careUS Strep A Plus is a useful test that showed highly comparable results with those of the culture test and superior performances among the three RADTs. The use of RADTs should be encouraged to provide acceptable and fast results using simple equipment.

ObjectiveTo compare the diagnostic performance of three rapid antigen detection tests (RADTs) for group AStreptococcus(GAS).DesignA hospital-based, cross-sectional, retrospective study.SettingA comparative study of rapid diagnostic tests for GAS using clinical specimens in a single institute.Participants225 children in the outpatient clinics ofKorea University Guro Hospitalwith suspicious symptoms were subjected to throat swab sampling. A dual-swab applicator was used. Samples were stored at below −70°C in a 10 mL transport tube containing 1 mL liquid Stuart’s transport medium.Outcome measuresAll tests were performed in the laboratory by trained clinical laboratory scientists. Sensitivity, specificity, accuracy and kappa index of three RADTs were compared with the reference PCR test and culture results.ResultsOf the 225 patients suspected of having GAS, 67 and 90 were positive for GAS in the culture and PCR tests, respectively. Compared with the reference culture, the sensitivity for GAS was 92.5% (CI 83.4 to 97.5), 71.6% (CI 59.3 to 81.9) and 74.63% (CI 62.5 to 84.4) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 97.0% (CI 93.1 to 99.0), 94.6% (CI 90.1 to 97.5) and 92.9% (CI 87.8 to 96.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively. Compared with the reference GAS real-time PCR, the sensitivity was 73.3% (CI 62.9 to 82.1), 63.3% (CI 52.5 to 73.2) and 67.8% (CI 57.1 to 77.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 99.3% (CI 95.9 to 99.9), 100.0% (CI 97.3 to 100.0) and 99.3% (CI 95.9 to 99.9) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively.ConclusionsThe careUS Strep A Plus is a useful test that showed highly comparable results with those of the culture test and superior performances among the three RADTs. The use of RADTs should be encouraged to provide acceptable and fast results using simple equipment.

Objective We compared the automated non-treponemal reagin (rapid plasma reagin (RPR)) test with the conventional RPR card test for usefulness in clinical applications. Setting A comparative study of laboratory methods using clinical specimens in a single institute. Participants A total of 112 serum samples including 59 Treponema pallidum particle agglutination (TPPA)-positive and 53 TPPA-negative specimens were evaluated. Outcome measures HiSens Auto RPR LTIA (HBI, Anyang, Korea) was compared with Macro-Vue RPR Card Tests (Becton Dickinson BD Microbiology Systems, Sparks, Maryland, USA). Treponemal-specific tests were performed by Serodia TPPA assay (Fujirebio, Tokyo, Japan). The percentage agreement, κ value and overall sensitivity and specificity of the two RPR tests were compared. Seroconversion rates after treatment were also compared for each RPR test. Results The percentage agreement between the two RPR tests was 78.6% (κ 0.565; 95% CI 0.422 to 0.709). Sensitivity and specificity of the automated RPR test relative to the TPPA test was 52.5% (95% CI 39.1% to 65.7%) and 94.3% (95% CI 84.3% to 98.8%), respectively, while the same values for the conventional RPR card test were 86.4% (95% CI 75% to 93.9%) and 94.3% (95% CI 84.3% to 98.8%), respectively. The conventional RPR card test showed overall higher positivity than the automated RPR test, whereas the automated RPR test showed higher seroconversion (43.5%, 10/23) than the conventional RPR card test (4.3%, 1/23) in treated patients. Conclusions The automated RPR test showed overall lower sensitivity than the conventional RPR test based on the treponemal test, but higher seroconversion after treatment. The automated RPR test could be used to monitor treatment response, especially in the reverse screening algorithm in syphilis testing.

Objective Elevation of C reactive protein (CRP) is one of the major acute-phase responses following ischaemic or haemorrhagic stroke. This study aims to investigate the associations between platelet indices, neutrophil-to-lymphocyte ratio (NLR) and erythrocyte sedimentation rate (ESR) compared with CRP in patients with cerebral infarction. Setting The clinical data of patients with cerebral infarction were analysed retrospectively. Participants We analysed, unduplicated, 516 patients with cerebral infarction (mean age 66.2±12.7, male/female=291/225). Outcome measures Mean platelet volume (MPV), MPV to platelet count, NLR and ESR were compared with CRP in patients with cerebral infarction in a single institute through Spearman correlation test. Results There were significant correlations between CRP and MPV (ρ=0.088, p=0.045), NLR (ρ=0.4, p