Abstract
Introduction: The bacteria responsible for pyothorax may be derived from the oral cavity; however, it has not been proven yet.
Objective: Our aim was to study if there is genetic homology between the bacteria in pus from the pyothorax and the bacteria in the oral cavity using Next-Generation Sequencing technology (NGS) in patients with pyothorax.
Methods: Two patients with pyothorax were studied. We aspirated pus from the pyothorax by fine-needle biopsy and sampled the bacteria in the oral cavity with a sponge. Cultured bacteria from the pus were isolated and identified by their 16S rRNA gene sequence. Then, we obtained its whole genome sequence by NGS using the MiSeq (illumina) platform. Based on this sequence and an already-known sequence of the same bacterial species, we generated five specific primers for the isolated pyothorax strain. We amplified total DNA that had been extracted from the oral bacteria using these specific primers by the PCR method and performed DNA sequencing.
Results: In both patients, we identified the Streptococcus anginosus group from the pus. In each patient, the sequence of the oral bacterial DNA that had been amplified by specific primers for the pyothorax strain completely matched the DNA sequence of the isolated pyothorax strain, while it did not match already-known sequences of the same bacterial species.
Conclusion: This study demonstrated genetic homology between the bacteria in pus from the pyothorax and oral bacteria at the strain level in pyothorax patients. This study proved for the first time that pyothorax is caused by oral bacteria, although the number of cases was limited.
- Copyright ©the authors 2016
