Can parents do a throat culture?

Area of Science:

• Pediatric infectious diseases
• Diagnostic accuracy studies
• Microbiology

Background:

• Group A beta-hemolytic Streptococcus (GABHS) is a common bacterial pathogen causing pharyngitis in children.
• Accurate and timely diagnosis of GABHS is crucial to prevent complications like rheumatic fever.
• Home-based testing could potentially improve access to diagnosis, but requires validation.

Purpose of the Study:

• To evaluate the accuracy of throat swabs collected by parents compared to physician-collected swabs for GABHS detection.
• To assess the impact of patient age on the accuracy of parent-collected throat swabs.
• To determine the sensitivity, specificity, and predictive values of parent-collected swabs.

Main Methods:

• Throat swabs were collected from 98 pediatric patients (ages 4-17) by both parents and physician investigators.
• Samples were tested for GABHS using a standardized method.
• Discrepancy rates, false negative rates, sensitivity, and predictive values were calculated and compared between parent and physician collections, stratified by age.

Main Results:

• Parental collection resulted in a 32% false negative rate for GABHS compared to physician collection (P < 0.001).
• The false negative rate was higher in younger children (4-8 years) at 38% compared to older children (P < 0.001).
• Overall sensitivity and negative predictive value for parent-collected swabs were 68% and 45%, respectively, with lower values in younger children.

Conclusions:

• The high false negative rate of parent-obtained throat swabs indicates poor reliability for diagnosing GABHS.
• Age significantly impacts the accuracy of parental sample collection, with younger children being more challenging.
• Current home testing protocols using parental throat swabs are not recommended due to insufficient diagnostic accuracy.