[Study on the medium (BALM) for isolation of Legionella pneumophila]

L. pneumophila was apparently using blue algae (cyanobacteria) extracellular products as carbon and energy sources for its proliferation. Based on this observation, a medium (BALM) in which all chemicals and reagents were made in China for isolation of L. pneumophila was developed. The recoveries of L. pneumophila serogroups 1 and 6 standard strains from contaminated air-conditional water and infected guinea pig spleens were evaluated by using two culture media: BALM and BCYE (buffered charcoal yeast extract agar). Recoveries of standard strains of L. pneumophila serogroup 1 were similar on both media, while those of L. pneumophila serogroup 6 were more efficient on BALM than on BCYE. In the process of isolation of L. pneumophila NANJ-1 strain, which was obtained from the material of tracheal lavage of a pneumonic patient in one of hospitals in Nanjing City, the recovery of this strain was also more efficient on BALM than on BCYE and other common used media. The results suggested that the use of BALM medium in place of BCYE may improve the recover of L. pneumophila from clinical and environmental specimens.