These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Duration of Group A Streptococcus PCR positivity following antibiotic treatment of pharyngitis.
    Author: Homme JH, Greenwood CS, Cronk LB, Nyre LM, Uhl JR, Weaver AL, Patel R.
    Journal: Diagn Microbiol Infect Dis; 2018 Feb; 90(2):105-108. PubMed ID: 29150372.
    Abstract:
    BACKGROUND: Polymerase chain reaction (PCR) has high sensitivity and specificity for detection of group A streptococcus (GAS) in throat swabs and is routinely used for GAS pharyngitis diagnosis at our institution. Herein we defined the natural history of throat swab GAS PCR and culture positivity during and following treatment of GAS pharyngitis. METHODS: Fifty children with a PCR positive GAS throat swab were recruited for participation. Four additional throat swabs were collected over 2 weeks following the initial positive PCR result (during and following a standard course of antibiotic therapy) and tested for GAS using rapid real-time PCR and culture. RESULTS: After the initial positive swab, 45% had a positive PCR 2-4 days, 20% 5-7 days, 18% 8-10 days, 25% 11-13days, and 20% 14-18days later. The median time to a negative PCR was 4 days with the nadir in positive PCR results approximating the end of a typical 10-day treatment interval. Seven subjects remained persistently PCR positive. Culture results remained positive at a stable rate for each time interval, ranging from 5-10%. CONCLUSIONS: If a patient presents with symptoms of GAS pharyngitis after previous positive GAS PCR testing and treatment with appropriate antibiotics, it is reasonable to use PCR testing for GAS pharyngitis testing beginning one week after initial testing. Further studies are warranted to determine if this time frame can be applied to PCR testing used to detect other infections.
    [Abstract] [Full Text] [Related] [New Search]