INFECTIVITY

LEGIONELLA

Q.Which of the following organisms, if found on a sputum culture, definitely indicates infection?
A. Chlamydia pneumoniae
B. Pneumococcus
C. Haemophilus influenzae
D. Legionella pneumophila
E. Moraxella

D. Legionella is not known to be a colonizer; if it is found on culture, it should be treated. While Mycoplasma and Chlamydia cultures are rarely sent, these organisms can be found in asymptomatic subjects, so their mere presence does not require treatment. Moraxella, Haemophilus, and Pneumococcus can also be colonizers in asymptomatic patients. However, they should be treated in a patient with clinical signs of pneumonia and one of these organisms

predominating in a sputum Gram stain and culture