Study of phase variation and intractable acute otitis media at the time of mixed infection of Streptococcus pneumoniae and Haemophilus influenzae

本文对37株中耳炎和31株鼻咽炎急性中耳炎肺炎球菌在无细菌培养的情况下进行了菌相分析。不透明菌落的比例在中耳分离株中显著高于鼻咽分离株。在中耳液和鼻咽液中观察到的PFGE图谱完全相同，但相态变化不同，这种差异可能是肺炎球菌适应不同选择性环境的结果。

Pneumococcal phase variation of 37 middle ear and 31 nasopharyngeal isolates obtained from children with acute otitis media was examined in the absence of intervening culture. The fraction of the opaque colonies was significantly higher in middle ear isolates than in nasopharyngeal isolates. We observed the identical PFGE pattern on the strains showing different phase variation pattern in the middle ear fluid and in the nasopharynx.The difference is probably the result of the pneumococci adapting to differential selective environments.