Comparison of the Gen-Probe Group A streptococcus Direct Test with culture and a rapid streptococcal antigen detection assay for diagnosis of streptococcal pharyngitis.

The objective of the study was to determine the correlation between group A streptococcal antigen detected from throat swabs with the culture results. A total of 1457 children had two swabs taken simultaneously, and culture and antigen detection were performed. There was a good correlation between antigen detection and isolation rates. In all, 225 strains of group A streptococcus were isolated;53 [57.6%] were from the 92 children with high antigen positivity, 68 [55.7%] were from the 122 children with medium antigen positivity and 77 [25.4%] were from 303 children with low antigen positivity;only 27 [2.9%] were from the 940 children with no antigen detected. We postulate that those who are antigen-positive, culture-negative carry the organisms in their throats, but they may be missed on culture because of the small number carried

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Evaluating the use of dedicated swab for rapid antigen detection testing in group a streptococcal pharyngitis in children

African Journal of Clinical and Experimental Microbiology ◽

10.4314/ajcem.v19i1.4 ◽

2017 ◽

Vol 19 (1) ◽

pp. 24

Author(s):

A.M. Sultan ◽

W.A Seliem

Keyword(s):

Streptococcal Pharyngitis ◽

Antigen Detection ◽

Group A

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Value of rapid test for identification of beta hemolytic Streptococcus antigens in children with Streptococcal pharyngitis

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh04s1039n ◽

2004 ◽

Vol 132 (suppl. 1) ◽

pp. 39-41 ◽

Cited By ~ 1

Author(s):

Branimir Nestorovic ◽

Suzana Laban-Nestorovic ◽

Veselinka Paripovic ◽

Katarina Milosevic

Keyword(s):

Group A Streptococcus ◽

Rapid Test ◽

Streptococcal Pharyngitis ◽

Early Spring ◽

Group A Streptococci ◽

Upper Respiratory Tract ◽

Isolation And Identification ◽

Cervical Lymph Nodes ◽

Group A ◽

Tract Infections

Beta-hemolytic group A streptococcus (Streptococcus pyogenes) is the most common bacterial agent associated with the upper respiratory tract infections in humans. The most frequently group A streptococcus-associated disease is pharyngitis. Males and females are equally affected by group A streptococcus. There is seasonal increase in the prevalence of group A streptococcus-associated pharyngitis. Streptococcal pharyngitis is most prevalent in winter and early spring with higher incidence of disease observed in crowded population such as school children. Early diagnosis and treatment of group A streptococcal pharyngitis has been shown to reduce the severity of symptoms and further complications such as rheumatic fever and glomerulonephritis. The conventional methods used for identification of group A streptococci depend on isolation and identification of the organism on blood agar plates. These methods usually require 18-24 hours of incubation at 37?C. Such delay in identifying the group A streptococcus has often made physicians to administer therapy without first disclosing the etiological agent. Development of immunologic tests, capable of detecting the group A streptococcal antigen directly from the throat swabs, produced rapid test results employed for better treatment of patients. STREP A test is a rapid immunochromatographic test for the detection of group A streptococci from throat swabs or culture. The accuracy of the test does not depend on the organism viability. Instead, group A strep antigen is extracted directly from the swab and identified using antibodies specific for the group A carbohydrates. We compared rapid test with conventional throat swab in 40 children, who met Centor criteria for streptococcal pharyngitis (absence of cough, high fever, purulent pharyngitis, enlarged and painful cervical lymph nodes). Overall congruence of rapid test and culture was 94%. Test is easy to perform and it is recommended as the first diagnostic test for management of children with streptococcal pharyngitis. In children with negative test, but with characteristics highly suggestive of streptococcal infection, throat culture should be performed.

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Rapid antigen detection test for group A streptococcus in children with pharyngitis

10.1002/14651858.cd010502 ◽

2013 ◽

Cited By ~ 3

Author(s):

Jérémie F Cohen ◽

Robert Cohen ◽

Martin Chalumeau

Keyword(s):

Group A Streptococcus ◽

Antigen Detection ◽

Rapid Antigen Detection Test ◽

Group A

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Molecular Testing for Detection of Groups A, C, and G β-Hemolytic Streptococci in Pharyngeal Samples from Children

The Journal of Applied Laboratory Medicine ◽

10.1373/jalm.2018.026104 ◽

2018 ◽

Vol 3 (3) ◽

pp. 429-437 ◽

Cited By ~ 1

Author(s):

Tam T Van ◽

Javier Mestas ◽

Jennifer Dien Bard

Keyword(s):

Group A Streptococcus ◽

Improve Patient Care ◽

Routine Care ◽

Streptococcal Pharyngitis ◽

Molecular Testing ◽

Culture Methods ◽

Rapid Antigen Detection Test ◽

Large Colony ◽

Group A ◽

Improve Patient

Abstract Background Group A Streptococcus (GAS) and large colony-forming group C (GCS) and G (GGS) β-hemolytic streptococci are important causes of acute pharyngitis in children and adults. Rapid and accurate diagnosis of streptococcal pharyngitis can improve patient care and potentially reduce transmission. In this study, we evaluated the performance of the Lyra Direct Strep (LDS) assay for detection of GAS and GCS/GGS compared with traditional culture methods. Methods Pharyngeal samples obtained from 278 children presenting to the emergency department with initial negative GAS rapid antigen detection test (RADT) were used. All samples were cultured as part of routine care and tested in batches using the LDS assay. Results Of 278 pharyngeal samples with negative GAS RADT, 37 (13.3%) and 63 (22.7%) patients were positive for GAS by culture and LDS assay, respectively. Four (1.4%) patients were positive for GCS or GGS by culture or LDS assay. The LDS assay demonstrated sensitivity and specificity of 97.6% and 89.0%, respectively, compared with culture as the gold standard. Repeat culture and an alternate PCR showed that 85.7% (24 of 28) of discrepant samples agreed with findings of the LDS assay. Since implementation, the LDS assay shows a positivity rate of 21.0% (281 of 1340) compared with 11.7% (246 of 2110) by culture in the previous year. Conclusions We successfully implemented the LDS assay at our institution and have observed a significant increase in the positivity rate of GAS compared with culture. The LDS assay alone allowed for the elimination of β-streptococci screening by culture at our institution.

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853. Epidemiology of Groups A, C, and G β-Hemolytic Streptococcal Pharyngitis

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz359.038 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S18-S19

Author(s):

James Ray Mata Lim ◽

Bobby L Boyanton ◽

Julie George ◽

Matthew Sims

Keyword(s):

Heart Disease ◽

Rheumatic Heart Disease ◽

Group A Streptococcus ◽

Retrospective Chart Review ◽

Streptococcal Pharyngitis ◽

Molecular Testing ◽

Age Difference ◽

Need For Treatment ◽

Group A ◽

Rheumatic Heart

Abstract Background Treatment of Group A Streptococcus (GAS) pharyngitis is imperative to mitigate sequelae such as rheumatic heart disease. The need for treatment of Group C Streptococcus (GCS) and Group G Streptococcus (GGS) pharyngitis is unclear, as rheumatogenic sequelae have not been well documented. Our institution switched from culture to molecular confirmation testing for a negative rapid streptococcal antigen detection test. Cultures reported GAS whereas molecular testing reported GAS, GCS, and GGS. We performed a retrospective chart review to examine the epidemiological differences of GAS, GCS, and GGS pharyngitis. Methods Records were obtained of pharyngeal samples from patients sent for testing at Beaumont Health Laboratory. In all, 92,369 records were analyzed. There were 47,106 records of cultures from May 2012 through December 2014 and 45,263 records of molecular testing from May 2015 to December 2017. Samples positive for either GCS or GGS were reported as positive for Group CG Streptococcus (GCGS). Epidemiological factors were evaluated. If available, electronic records from GCGS positive samples were evaluated for clinical features, antibiotics used, and sequelae or complications reported. Results Molecular testing showed GAS positivity of 9.3% (n = 4,189) and GCGS positivity of 1.5% (n = 687). GCGS pharyngitis was more likely during the summer months and in young adults 13 years and older than children under 13 years. GAS pharyngitis was more likely during spring months and in children aged 4–9 years. Mean age of GCGS pharyngitis was 13 vs. 8.6 years for GAS pharyngitis. Similar results were obtained for GAS between culture and molecular testing records. Amoxicillin was most often prescribed for treatment of GCGS. There were few instances of severe GCGS exudative or recurrent pharyngitis that required hospitalization or tonsillectomy. There were no cases of rheumatic fever or rheumatic heart disease associated with GCGS. Conclusion This is the largest study based on our literature review to evaluate the epidemiology of GAS, GCS, and GGS pharyngitis in children and adults. We found a seasonal and age difference between GAS and GCGS. Complications were rare, and no rheumatogenic sequelae were noted from GCGS infections. Disclosures All Authors: No reported Disclosures.

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