When Bartonella bacteria are present in the body, the immune system creates antibodies that help eliminate them. Test methods, such as immunofluorescence assays (IFA), determine the level of IgM and/or IgG antibodies circulating in a patient, which can be useful for diagnosis of bartonellosis and monitoring treatment response.
Almost 20 Bartonella species have been implicated in human and animal diseases. Galaxy Diagnostics offers the broadest IFA serology panel available, targeting the 4 species that are most commonly found in studies published by the Bartonella Project at NC State University College of Veterinary Medicine.
Species
Bartonella henselae
Bartonella henselae is the causative agent of cat scratch disease and implicated in systemic diseases affecting the heart, central nervous system, eyes, bones, and joints. B henselae has been documented in people and animals worldwide. Transmission is thought to occur primarily in the context of contact with cats and fleas. Transmission by needlestick, tick bite, spider bite, and contact with lice has also been reported in the medical literature.
Bartonella quintana
Bartonella quintana has been documented worldwide in people who live outdoors in rough settings with poor hygiene. Transmission is thought to occur primarily through contact with rodents and body lice.
Bartonella vinsonii berkhoffii
B. vinsonii berkhoffii infection has been documented worldwide in people who live and work with animals, especially veterinary workers, and can lead to systemic diseases. Transmission is thought to occur primarily in the context of contact with dogs and fleas.
A 2010 case report described a veterinarian who developed non-specific symptoms including headaches, fatigue, and intermittent paresthesia following an accidental needle stick after working with an ill dog. Evidence of B. vinsonii berkhoffii infection in the dog was confirmed using PCR testing following BAPGM™ enrichment of a mass aspirate. Both IFA serology and PCR testing following BAPGM™ enrichment were used to confirm B. vinsonii berkhoffii infection in the veterinarian.
Bartonella koehlerae
B. koehlerae infection is associated with cats and their fleas, like B. henselae, and has been implicated in illnesses impacting the central nervous system in people. Commercial testing for this species is not available anywhere else in the world at this time.
A 2011 case report described an 18-year-old woman with hallucinations and visual deficits who tested positive for B. koehlerae using both IFA serology and PCR testing following BAPGM™ enrichment. Her symptoms resolved following antimicrobial therapy.
An advantage to Galaxy’s Bartonella IFA Serology tests is the high specificity for Bartonella species that affect cats, dogs, and people.
A 2020 NCSU study showed a specificity of 97% for B. henselae, B. vinsonii berkhoffii, and B. koehlerae in nearly 16,000 dogs that were suspected of having a vector-borne infection. Like the NCSU Bartonella research team, Galaxy Diagnostics uses cell-culture-derived antigens derived from patient Bartonella isolates to ensure the highest levels of sensitivity and specificity.
A big limitation of any type of serology testing for Bartonella, however, is that patients may not always produce detectable antibodies. Research suggests that patients who do not produce detectable antibodies may test positive by direct detection via ddPCR or Digital ePCR™.