Impact of technical training on rapid antigen detection tests (RADT) in group A streptococcal tonsillopharyngitis.

ABSTRACT

Rapid antigen detection tests (RADT) are widely used for the rapid diagnosis of group A streptococcal (GAS) tonsillopharyngitis. In a prospective 3-year study, the reliability of two different RADT methods was compared, as performed by lab technicians versus physicians. Sensitivity and specificity, as well as positive and negative predictive values, were calculated. When performed by physicians, the results (44.4 %, 8.3 %, 26.7 % and 16.7 %) of a latex agglutination test (LAT) were unacceptably low. However, after switching to a lateral-flow immunoassay (LFIT) and implementing additional hands-on training, the performance improved dramatically (100 %, 92.6 %, 84.6 % and 100 %). In conclusion, technical errors, along with a lack of experience and expertise, negatively impact RADT accuracy.