ISOLATION OF LEGIONELLA-PNEUMOPHILA FROM CLINICAL SPECIMENS - SALUTARY EFFECTS OF LUNG-TISSUE DILUTION

Abstract
Diagnosis of Legionnaires'' disease is seldom confirmed by isolation of L. pneumophila. In 2 [human] cases, isolates were obtained using inocula of diluted lung tissue suspensions, even though no growth occurred when undiluted suspensions were used. Tissue dilution apparently decreases the concentration of antimicrobial agents and antibacterial properties associated with lung host defense mechanisms, which allows improved recovery rates. This technique is recommended when attempting isolation of L. pneumophila from clinical specimens.