Antibiotic therapy following polymerase chain reaction diagnosis of infective endocarditis: a single centre experience

OBJECTIVES: Conventional culture methods often fail in the aetiological diagnosis of infective endocarditis (IE), complicating adequate IE treatment. Therefore, in addition to culture diagnostic methods, our clinical department uses a broad-range 16S and 18S rDNA polymerase chain reaction (PCR) and sequencing test to detect and identify IE agents. METHODS: Between 2009 and 2013, we performed 246 valve replacements due to endocarditis. In 46 patients with culture-negative IE or incongruent preoperative microbiological diagnostics, heart valve (HV) samples were PCR-analysed and PCR products subsequently sequenced for phylogenetic analysis. RESULTS: The molecular diagnosis led us to change the antibiotic regimen in 7 of 46 patients. CONCLUSIONS: The PCR results demonstrate that the molecular test is a useful diagnostic tool for the rapid diagnosis of IE. Furthermore, the molecular diagnosis had a significant, direct impact on the therapy of IE. This suggests that using PCR can improve antibiotic treatment, particularly in cases of culture-negative IE. Consequently, molecular analysis of micro-organisms in HV samples should be performed routinely where preoperative diagnosis remains unclear.