NEWLY IDENTIFIED BACTERIUM PHENOTYPICALLY RESEMBLING, BUT GENETICALLY DISTINCT FROM, LEGIONELLA-PNEUMOPHILA - ISOLATE IN A CASE OF PNEUMONIA

A bacterium with growth characteristics similar to, but genetically distinct from, either Legionella pneumophila or WIGA (a 'rickettsia-like agent') was obtained from a postmortem lung specimen of a patient with fatal atypical pneumonia at the M.D. Anderson Hospital and Tumor Institute in Houston, Texas. This bacterium and WIGA have essentially the same cellular fatty acid composition, which is distinct from that of L. pneumophila. Deoxyribonucleic acid-relatedness studies show that the isolate from Texas is only about 10% related to both L. pneumophila and WIGA and therefore may represent a new species. This new bacterium should be considered in selecting laboratory procedures in the diagnosis of atypical pneumonia.