Role of Rapid Antigen Detection Test (RADT) and Throat Culture in the Diagnosis of Streptococcal Pharyngotonsillitis

Abstract

Objective:  To observe the sensitivity and specificity of the rapid antigen detection test and throat culture in the diagnosis of pharyngo tonsillitis.

Study Design: An Experimental study

Place and Duration of Study: This study was conducted in microbiology department, basic medical sciences institute, Jinnah post graduate medical centre, National institute of child health, and civil hospital Karachi, from May 2003 – April 2004.

Materials and Methods: A total of 300 children attending OPD’s and admitted (250 suspected and 50 Normal as control cases) of age group 5 – 15 years were included in this study and this age group was again divided into three sub groups I.e: first group from 5 – 8 years, second group was from 9 – 12 years, and the third group was from 13 – 15 years.

Results:  Rapid antigen detection test carried out was based on immuno - chromato graphic membrane assay procedure, a total of 24 positive antigen detection test from suspected 250 cases and 5 from 50 control cases were isolated and these isolated (RADT positive) cases were again confirmed by throat culture. The Bacitracin sensitivity and catalase tests were also performed.

Conclusion: The Rapid antigen detection test (RADT) is a rapid way of diagnosing the group A, Beta hemolytic streptococci, result can be obtained within 5 – 10 minutes so the treatment may be started accordingly, while the throat culture is still considered as the Gold standard for the diagnosis of group A beta hemolytic streptococcal pharyngotonsillitis. The positive as well as negative RADT cases were confirmed by the culture.