by The 5th annual LymeMIND Virtual Conference held in October 2020 is available online. A session on “Bartonella and Co-infections” featured several speakers, including two Galaxy Diagnostics scientists. The speakers focused on what we know now about Bartonella species infection in people and hypotheses to drive future research. These hypotheses all require more advanced molecular and microscopy test methods that directly detect evidence of the bacteria.
- Marna Ericson, PhD, who presented first, discussed microscopy findings in detail and showed an example that clearly illustrated the differences between stretch marks and striae. Striae resemble scars and typically have more Bartonella bacteria present in the collagen. She also reported on finding Bartonella in a biofilm found on a PICC (peripherally inserted central catheter) line. In the lab, they found that Bartonella henselae grew best on a collagen matrix. The hypothesis researchers in her lab have developed is that the dermis is a primary niche for Bartonella species. The infection is introduced through the skin, where it is able to escape immune surveillance. It is also able to enter the vascular system and travel to other organs.
- Monica Embers, PhD, then presented on “Modeling Bartonella Infection for Human Health Risk and Pre-clinical Studies.” Dr. Embers and her team at Tulane University are using a one health approach to better understand bartonellosis in humans. The lessons learned from developing the best laboratory animal model for Bartonella will have applications for other vector-borne diseases, like Lyme borreliosis and babesiosis. One of their roadblocks is that common laboratory animals such as mice tend to have high levels of these bacteria for only a short amount of time. A mouse that is immunocompromised may develop a sustained higher bacterial load, but it might also not be the best model for a typical human infection. Consequently, researchers require very sensitive testing to be able to follow what is going on in their immunocompetent mice. Early results from their research suggest that when Borrelia burgdorferi is present, Bartonella species invade more kinds of tissues. The hypothesis researchers have developed is that “mice co-infected with Bartonella species and Borrelia burgdorferi will have a more broadly disseminated and persistent infection than mice singly infected with Bartonella.”
- Edward Breitschwerdt, DVM (co-founder of Galaxy Diagnostics), presented on neuropsychiatric illness related to Bartonella species infection. He discussed three previously published case studies of patients with neuropsychiatric symptoms which improved after bartonellosis was diagnosed and antibiotic treatment was initiated. In all three patients, identification of a Bartonella species infection was delayed because it was not considered in the initial possibilities for diagnosis.
- Bob Mozayeni, MD (medical director at Galaxy Diagnostics), spoke on “vascular and lymphatic mechanisms for encephalopathy & distinction from Lyme borreliosis”. He observed that symptoms of bartonellosis are mainly the result of “endothelial inflammation, damage to collagen and systemic inflammation.” We previously wrote about Dr. Mozayeni’s presentation at the European Crypto-Infections Conference in 2020, where he discussed the role of Bartonella species in small vessel disease. Bartonellosis and borreliosis can often be confused because they are both transmitted by arthropod vectors and the non-specific symptoms reported by chronically ill patients greatly overlap. Further, serology (tests for antibodies), test results can be difficult to interpret due to documented cross-reactivity between Bartonella and Borrelia antigens. He reminded the audience that it is important to confirm diagnoses with molecular testing when possible.
- Neil Spector, MD, passed away prior to the conference. Dr. Mozayeni introduced a presentation Dr. Spector had previously recorded at the ILADS conference. Dr. Spector had a heart transplant following misdiagnosed Lyme carditis, and his own experience as a patient drove his research on pathogens and cancer, which led to his focus on bartonellosis. His research found Bartonella species bacteria in primary tumors from inflammatory breast cancer. Research has also shown upregulation of HER2 and HER3 in a short amount of time after tissue is exposed to Bartonella species. Bartonellosis causes changes in cells that are also present in about 15% of all cancers. Further research is needed to determine how frequently these changes in cancer cells are associated with Bartonella species.
Other researchers at his laboratory at Duke University have taken up this research, using not just molecular testing for pathogens but also very specific biological pathway testing to better understand how these pathogens affect the activities of the cell.
Conclusion
The breadth of human disease associated with bartonellosis presented just in these few speeches includes dermatological symptoms, neuropsychiatric symptoms and oncology. Microbiome and pathogen research is an untapped area of medical research, and Bartonella species bacteria are already being found across areas of study.