[Reasons for low usage of strep A rapid antigen detection tests for pharyngitis in private medical practice]. / Motifs de la mauvaise utilisation des tests de diagnostic rapide du streptocoque de groupe A en médecine libérale.

ABSTRACT

UNLABELLED Rapid group A Streptococcus (GAS) antigen detection tests (RDT) have high diagnostic performance for the management of acute pharyngitis and are recommended before any antibiotic (ATB) prescription in France to reduce ATB use. The rate of general practitioners (GPs) using GAS RDT is low and decreasing. Our aims were to describe the reasons for pediatricians and GPs not using RDT or for prescribing ATB despite of a negative RDT. METHODS: In 2011, a survey was conducted in a random sample of 368 GPs plus all ambulatory pediatricians (n=82) in the Nord-Pas-de-Calais region of France. RESULTS: Response rates were 74% (n=61) for pediatricians and 18% (n=68) for GPs. RDTs for pharyngitis were used by 75% [95% CI 63-85] of pediatricians and 53% [95% CI 41-64] of GPs (P<0.001). RDTs were systematically used in children 3years of age and older by only 59% of all physicians using RDTs. An ATB was systematically prescribed in case of positive RDT by 96% of physicians and eventually prescribed in case of negative RDT by 74%. The main reasons for ATB prescription in case of negative RDT were association with otitis media (51%), second visit for the same pharyngitis (45%), and high clinical suspicion of GAS pharyngitis (36%). Forty percent of non-RDT users had used them in the past. The 3 main reasons for not using RDT were the lack of time (57%), high confidence in clinical data to discriminate GAS pharyngitis (48%), and low confidence in RDT (27%). DISCUSSION: This survey highlights the lack of knowledge about low and high discriminant values of clinical data and RDT, respectively, especially the excellent negative predictive value of RDTs, and an erroneous assessment of the low risk of missing GAS pharyngitis compared to the consequences of inappropriate ATB use.