Legionella Ab

Keywords: Legionella antibody, Legionella sp antibody, Legionella species antibody, Legionella serology

Specimen:

5-10 mL blood in plain tube, collected at onset of disease and 4-6 weeks later (convalescent).

Method:

IFA.

Application:

Investigation of pneumonia.

Fever.

Interpretation:

Confirmation of Legionella infection depends on detecting a four-fold increase in titre to ≥ 128. A single titre of ≥ 256 is suggestive of infection.

Polyvalent antiserum is used to detect antibodies to serogroups 1-6 of L. pneumophila.

Monovalent antisera are used to identify antibodies to other species, eg, L. longbeachae, L. micdadei.

Seroconversion may take up to 6 weeks. A convalescent sample is required for optimal diagnosis.

Reference:

Murdoch DR. Clin Infect Dis. 2003; 36: 64-69.

Waterer GW et al. Am J Med. 2001; 110: 41-48.