11.5.2015

The diagnostics of group A streptococcus from pharyngeal swab samples by bacterial culture is challenged by a novel mariPOC point of care test.

Journal of Clinical Microbiology has published the study about point of care testing of group A streptococcus conducted by Dr. Jukka Vakkila.

Abstract:

The diagnostics of group A streptococcus from pharyngeal swab samples by bacterial culture is challenged by a novel mariPOC point of care test.

mariPOC® is a novel point-of-care test system for rapid detection of respiratory tract infections. We compared the performance of mariPOC® to bacterial culture for detecting group A streptococcus (GAS) in 219 pharyngitis patients (ages 1-64 years) and 109 healthy asymptomatic controls (19-69 years). In addition, 42 patient samples were analyzed by quantitative PCR (qPCR). Of the 219 pharyngeal patient samples, 32 were positive in GAS bacterial culture (prevalence 15%) and 65 (30%) in mariPOC®. The amount of GAS in samples reported positive by mariPOC and negative by culture was, on average, 10-fold less compared to that of those positive in both methods. This indicated that the negative results in bacterial culture were due to lower sensitivity. qPCR results were positive and in line with the mariPOC® results in 43% of the discordant samples studied. Two GAS culture positive samples were negative by mariPOC®. The prevalence of GAS in the control subjects was 2 % and 6 % by culture and mariPOC®, respectively. We conclude that the mariPOC® antigen detection test is more sensitive than conventional bacterial culture for detection of GAS among symptomatic pharyngitis patients. The higher prevalence of GAS by mariPOC® among symptomatic patients was unlikely due to the carriership, since among the control patients the difference in the prevalence of GAS by mariPOC and culture was not nearly as high, 15% vs. 4% respectively. Clinical trials are needed to show the clinical importance of our finding.

Read more: Pubmed