Tests for the diagnosis of brucellosis, leptospirosis, Q fever and rickettsioses
| Culture | Nucleic acid amplification | Serology | Comments | |
|---|---|---|---|---|
| Brucellosis | X | X | X | Culture: bone marrow cultures are more sensitive than blood cultures.
NAAT: sensitivity is highest in tissue samples. Serology: four-fold rise in Brucella antibody titre between paired sera. |
| Leptospirosis | X | X | X | Culture: poor sensitivity.
Serology: four-fold rise in Leptospira antibody titre between paired sera or single titre ≥1:800 |
| Q fever | X | X | X | NAAT: sensitivity is highest for whole blood samples within 2 weeks of symptom onset.
Serology: acute Q fever, four-fold rise in phase II IgG between paired sera; chronic Q fever, phase I IgG titres ≥1:1,024. |
| Rickettsiosis | X | X | X | NAAT: sensitivity in blood is low, but high when applied to skin biopsy.
Serology: four-fold rise in Rickettsia spp antibody titre between paired sera. |
IgG = immunoglobulin G; NAAT = nucleic acid amplification test.