Context
Diagnosis of infective endocarditis (IE), particularly in blood culture-negative patients, has been a problem and requires further investigations.
Aim
This study was designed to evaluate the added value of a commercial multiplex PCR performed on blood in the early diagnosis of IE and compare its performance with conventional blood culture and serological testing, at a tertiary care center in Egypt.
Settings and design
Thirty-seven cases of diagnosed definite endocarditis were enrolled in the study.
Patients and methods
For each patient, blood culture was prepared and serum sample was obtained for serology testing for spp., spp., antibodies, and galactomannan antigen. Patients were selected for commercial Seegene multiplex PCR (sepsis screening) when their blood culture remained negative after 24 h incubation.
Statistical analysis
Sensitivity, specificity, positive predictive value, negative predictive value, and κ-test were used in statistical analysis for agreement.
Results
Thirty-seven cases were diagnosed as having definite IE. Causative organisms were detected using blood cultures in 18.9% (7/37) of cases after 24 h of incubation. Blood culture remained negative in 81% (30/37) of cases until the end of 21 days of incubation. One case showed positive result in serological testing for galactomannan Ag, whereas serological tests for spp., , and spp. were negative in all cases. Multiplex PCR (sepsis screening) showed positive results in 51.3% (19/37) of definite IE cases.
Conclusion
The added value of multiplex PCR to conventional blood culture and the serological testing decreased the percentage of unidentified cases of IE from 81 to 48.7% in the selected study group.