Cardiology Research, ISSN 1923-2829 print, 1923-2837 online, Open Access
Article copyright, the authors; Journal compilation copyright, Cardiol Res and Elmer Press Inc
Journal website https://www.cardiologyres.org

Original Article

Volume 9, Number 2, April 2018, pages 99-106

Molecular Diagnosis of Bacterial Definite Infective Endocarditis by Real-Time Polymerase Chain Reaction

Figures

Figure 1.
Figure 1. Agarose gel electrophoresis of primer designing and a non-template control (NTC) reaction.
Figure 2.
Figure 2. Amplification (a) and melting curves (b) of 13 positive whole blood samples placed in duplicate manner. The identified bacteria were: S. gallolyticus (red line), S. sanguines (blue line), S. salivarius (violet line), S. aureus (orange line), S. mutans (green line), and E. faecalis (black line).

Tables

Table 1. Primer Used in This Study
 
BacteriaTarget geneForward primer (5′-3′)Reverse primer (5′-3′)Size (bp)References
S. aureuseapTACTAACGAAGCATCTGCCTTAAATCGATATCAC TAATACCTC230[22]
S. epidermidisSEICTAAAGAAGAAGCAAATCGTATAGATATTGGTTGTGGTGAT105This study
S. pyogenessodAAATATCTTCTGGAATCTTAGTGACTTATGTCGCTAATACCAATG101This study
E. faecalisddlCAATAACACGATTGAAATGCACTTCCATCTAACATAATATACG103This study
S. mitisSM1TGTCAGATAATGCTAATAAGATGATCAGAAAGGTTGTTAATGTC197This study
S. mutansgtfBAGAGGAATATACCAATGTTGTGAAGAACCATCTGTTGAAGAC110This study
S. sanguinesgtfpGACTGATGAGAAGATTACCATGTTGAGATATTCGTTGCTA113This study
S. salivariusMAPGGGAAGCATTATGGATTACCACACATCAAGGACTGACTTATC155This study
S. gallolyticusrecNSGGAAAGCTGGTGAGGACCAAGCCATTTCTTTATAGTCAGCATCA189This study

 

Table 2. Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Value of Blood Culture and Real-Time PCR
 
Diagnostic approachBlood culture (95% CI)Real-time PCR (95% CI)
Sensitivity5% (0.13% to 24.87%)65% (40.78% to 84.61%)
Specificity100% (83.16% to 100.00%)100% (83.16% to 100.00%)
Positive predictive value100%100%
Negative predictive value51% (48.77% to 53.79%)74% (61.12% to 83.85%)

 

Table 3. Microbiologic Findings of Real-Time PCR and Culture of Blood for 20 Patients With Definite IE
 
Patient no.Previous history of antibiotic therapyBlood cultureBlood real-time PCR
1YesNegativeNegative
2YesNegativeE. faecalis
3YesNegativeS. aureus
4YesNegativeNegative
5YesNegativeE. faecalis
6YesNegativeNegative
7YesViridans streptocococciS. sanguines
8YesNegativeE. faecalis
9YesNegativeNegative
10YesNegativeS. gallolyticus
11YesNegativeNegative
12YesNegativeS. mutans
13YesNegativeE. faecalis
14YesNegativeE. faecalis
15YesNegativeE. faecalis
16YesNegativeNegative
17YesNegativeS. gallolyticus
18YesNegativeS. salivarius
19YesNegativeNegative
20YesNegativeE. faecalis