Diagnostic Accuracy of Rapid Molecular Tests for Group A Streptococcal Pharyngitis Using Saliva Samples

Summary

Observational study evaluating the diagnostic accuracy of rapid point-of-care molecular Group A strep diagnostic tests in saliva as compared to standard culture- and PCR-based techniques for the management of children aged 3-15 years of age presenting with sore throat to primary care.

Conditions

• Streptococcal Pharyngitis

Interventions

DIAGNOSTIC_TEST

Index test: Abbott ID NOW STREP A 2

The test under evaluation ('index test') is the rapid molecular test for Group A streptococcus Abbott ID NOW STREP A 2 (performed on saliva samples instead of throat swabs). This test was chosen because of its ease of use and several previous evaluations showing high diagnostic accuracy on throat swabs. The test gives a result after 2 to 6 minutes and will be performed by primary care practitioners participating in the study, in their office, using salivary swabs instead of throat swabs. Investigators will receive one session of specific training prior to the study. Saliva samples will be collected using the cotton swab that comes within the test packages. Index test results will not be used for patient management. Clinicians performing the rapid saliva test will not be blinded to clinical information.

DIAGNOSTIC_TEST

Reference standard test: Composite of culture and PCR-based tests based on a throat swab

Throat samples will be obtained by use of a double-swab collection-transportation system : * Swab #1 will be used to perform the rapid antigen detection test (see below) * Swab #2 will be held at ambient temperature and sent within 72 hours to Robert Debre Hospital microbiology laboratory. Throat swabs will be used to perform throat cultures using standard techniques (PMID: 22768060). Throat swabs will also be used to perform a PCR specific for Group A streptococcus (PMID: 23465407). Samples with a positive culture and/or a positive PCR test result will be classified as reference-standard-positives. Samples with a negative culture and a negative PCR will be classified as reference-standard-negatives. Investigators will be blinded to clinical data, including the result of the rapid antigen detection test and the rapid saliva test.

DIAGNOSTIC_TEST

Comparator test: Rapid antigen detection test (usual care)

As per usual care, all children will undergo a rapid antigen detection test (StreptAtest, Biosynex), using Swab#1 (see above). This rapid antigen detection test is the one used in France and is the only commercial kit that is officially recommended by the National Health Insurance system. It detects Lancefield's Group A antigen, which is specific to Group A Streptococcus. The test will be performed by investigators, during consultation time. Clinicians performing the rapid antigen detection test will not be blinded to clinical information.

Sponsors & Collaborators

• Hôpital Necker-Enfants Malades

  collaborator OTHER

• University Hospital, Paris

  collaborator OTHER

• Groupe Hospitalier Diaconesses Croix Saint-Simon

  collaborator OTHER

• Association Clinique Thérapeutique Infantile du val de Marne

  collaborator OTHER

• Centre Hospitalier Intercommunal Creteil

  lead OTHER

Eligibility

Min Age

3 Years

Max Age

15 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-01-31

Primary Completion

2025-01-31

Completion

2025-02-28

Countries

• France

Study Locations