Polymerase chain reaction for Streptococcus pyogenes used to evaluate an optical immunoassay for the detection of group A streptococci in children with pharyngitis
| Autor: | Patricia L. Welby-Sellenriek, Gregory A. Storch, Michael G. Caparon, Jorge Diego, Rhonda Ferrett, Gustavo Kaltwasser |
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| Rok vydání: | 1997 |
| Předmět: |
Microbiology (medical)
food.ingredient Streptococcus pyogenes medicine.disease_cause Polymerase Chain Reaction Group A Microbiology law.invention food Antigen law Streptococcal Infections medicine Humans Agar Child Polymerase chain reaction Immunoassay Antigens Bacterial medicine.diagnostic_test biology business.industry Pharyngitis Streptococcaceae biology.organism_classification Infectious Diseases Pediatrics Perinatology and Child Health medicine.symptom business |
| Zdroj: | The Pediatric Infectious Disease Journal. 16:748-753 |
| ISSN: | 0891-3668 |
| DOI: | 10.1097/00006454-199708000-00004 |
| Popis: | Background In evaluations of sensitive rapid tests for group A streptococci such as the optical immunoassay (OIA), some samples are positive by the antigen test but negative by culture. A method is needed for resolving these discrepant results. Objective To develop a PCR-based assay to detect group A streptococci and to use it to establish a reference standard for evaluating an OIA for group A streptococcal antigen. Methods A PCR assay that detects a segment of the MF gene of Streptococcus pyogenes was developed for the detection of group A streptococci in throat swabs. Paired swabs were obtained from 200 children with symptomatic pharyngitis and used to perform OIA, agar culture, broth-enhanced culture and PCR. As a reference standard any patient with group A streptococci detected by either culture or PCR was considered to be truly positive. Results In comparison to agar and broth-enhanced culture procedures, OIA had sensitivities of 82 and 80% and specificities of 87 and 89%, respectively. Eight (44%) of 18 samples that were positive by OIA but negative by culture were positive for group A streptococci by PCR. Compared with the reference standard, sensitivities were OIA 76%, agar culture 79%, broth-enhanced culture 86% and PCR 96%. The specificity of OIA was 92%. Conclusions PCR can be used to establish a reference standard for evaluating rapid tests for group A streptococci. With this reference standard OIA was nearly as sensitive as but less specific than agar culture for detection of group A streptococci. Maximum detection requires use of both tests. |
| Databáze: | OpenAIRE |
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