Normal range: Negative
Comment: Over 34 species in the Legionellaceae family of bacteria have been discovered since Legionella pneumophilia was first recognized. Thirteen species have been implicated pneumonia. A four fold rise in titer to > 1: 128 is evidence of recent infection. A single titer ³ 1: 256 is evidence of infection at an undetermined time in the past. However, due to the relatively high prevalence of antibodies to Legionella pneumophilia, acute and convalescent titers are preferred to a single sample. Most seroconversions can be documented within 3 weeks of onset
Sample: Serum