Table 1.
Diagnosis* |
||||
---|---|---|---|---|
Concurrent findings | Direct identification techniques | Serology | Comments | |
Flea-associated pathogens | ||||
Bartonella species | • Endocarditis • Hyperglobulinemia • Lymphadenopathy • Myocarditis • Osteomyelitis • Uveitis • Other |
• Silver stain on exudates or tissues • Culture of blood or tissues • PCR assay on blood or tissues |
• Several techniques available in some laboratories | • The combination of serology plus culture and PCR has the greatest diagnostic sensitivity |
Coxiella burnetii | • Abortion • Stillbirth |
• PCR assay on blood | • Available in some laboratories | • Difficult to culture • The role that fleas play in the transmission of this agent is still being explored |
Hemoplasmas | • Hemolytic anemia | • Blood smear cytology • PCR assay on blood |
• Not commercially available | • Organisms on erythrocyte surface • Cytology is falsely negative in many cases and does not allow speciation • PCR is preferred diagnostic method |
Rickettsia felis
Rickettsia typhi |
• Currently unknown | • PCR assay on blood | • Not commercially available | |
Yersinia pestis | • Lymphadenopathy • Cough |
• Cytology • Fluorescent antibody staining • Culture • PCR assay |
• Available in some laboratories | • Lymph nodes, abscesses and airway wash samples used for direct identification techniques • Rising titers can be used to confirm recent infection if direct techniques are negative |
Results of direct tests (cytology ± staining techniques, culture, PCR assays) confirm infection when they are positive. However, for some agents, such as Bartonella species and the hemoplasmas, there is a carrier phase in many healthy cats and so positive test results do not confirm disease induced by the agent. Similarly, most positive antibody test results merely indicate past or current infection, but do not confirm current infection or disease