Legionella pneumophila, DFA

Determine the presence of Legionella pneumophila organisms in direct FA smear of specimen, providing rapid diagnosis.

Test does not include Legionella species other than L pneumophila.

Community-acquired and nosocomial infections caused by multiple serogroups of Legionella are increasingly recognized. Although culture is now possible on buffered charcoal yeast extract agar, the demonstration of organisms in tissue or brushings is the fastest way to make the diagnosis. It also has the advantage of applicability to specimens contaminated with other bacteria. Development of monoclonal antibodies have increased sensitivity and specificity. False-positive reaction has been reported in a case of pleuropulmonary tularemia and in cases of Campylobacter infection.

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