A recent study conducted by researchers at North Carolina State University has shed light on a potential connection between Bartonella bacteria and mental health. The study found that patients diagnosed with schizophrenia or other psychotic disorders were three times more likely to have Bartonella DNA in their blood compared to adults without these conditions.
The Role of Bartonella
Bartonella is a group of vector-borne bacteria primarily transmitted by arthropods such as fleas, lice, and ticks. These bacteria can also be transmitted through animals that harbour them. While some Bartonella species are known to cause cat scratch disease, recent research suggests that they may play a broader role in human health.
Study Details
The research team analysed blood samples from 116 individuals, including control subjects, prodromal patients (those with symptoms but no formal diagnosis), individuals with psychosis, and close relatives of those diagnosed with psychosis. The samples were collected during a biomarker research study conducted at the Columbia University Irving Medical Center.
In a previous study at Columbia, patients with psychosis were found to have increased inflammatory markers in their blood. Dr. Edward Breitschwerdt, an infectious disease researcher at NC State’s College of Veterinary Medicine, wanted to explore potential drivers of inflammation in neuropsychiatric illnesses. Given the associations observed between Bartonella and mental health symptoms in prior work, Bartonella infection emerged as a possible candidate.
Detecting Bartonella DNA
The NC State team used immunofluorescence assays and digital droplet PCR testing to detect and amplify Bartonella DNA in the blood samples. Although the blood samples had been frozen and stored, the researchers did not attempt to culture bacteria from them. Culturing the bacteria could enhance DNA detection further.
The results revealed that 43% of participants diagnosed with psychosis had Bartonella DNA in their blood, compared to only 14% in the control group. Additionally, DNA sequencing allowed the identification of specific Bartonella species in 18 of the 31 participants with Bartonella DNA. These species included Bartonella henselae, Bartonella vinsonii subsp. berkhoffii, Bartonella quintana, Bartonella alsatica, and Bartonella rochalimae.
Implications and Future Research
This study is the second to identify Bartonella in the blood of psychiatric patients. A 2020 study at the University of North Carolina School of Medicine found Bartonella species DNA in 65% of patients with schizophrenia, compared to only 8% in healthy volunteers.
Dr. Breitschwerdt emphasises the need for further investigation. “We’ve now demonstrated the presence of Bartonella species in the blood of two separate cohorts of patients with neuropsychiatric symptoms,” he says. “These findings warrant additional research to determine whether Bartonella plays a role in mental illness.”
As researchers continue to explore the link between infectious agents and psychiatric disorders, understanding the potential impact of Bartonella could lead to new insights and treatment approaches.
