New research is the latest to find evidence of a link between mental illness and infections caused by a group of bacteria commonly found in cats and other animals. The small study found that people diagnosed with schizophrenia and schizoaffective disorder were more likely to carry Bartonella bacteria in their bloodstream than a control group of patients. However, more research is needed to definitively show whether these infections can contribute to mental illness.
Acute infections involving Bartonella bacteria can be especially serious for people in poor health or with a weakened immune system. In most people, they are thought to cause only mild, short-term illness. Yet for years, Ed Breitschwerdt and his fellow researchers at North Carolina State University have theorized that the health effects of these infections may be more profound in at least some unfortunate people.
Your previous job has outstanding the case of a 14-year-old boy who suddenly developed schizophrenia-like symptoms and was later found to be carrying a species of Bartonella known to cause cat scratch fever. In that case, the boy’s serious psychiatric problems seemed to disappear once his chronic Bartonella infection was treated with antibiotics. Last year, they published The research found that other people with similar neuropsychiatric symptoms often carried these bacteria, along with physical symptoms of an ongoing infection that appeared around the same time, as distinct skin lesions.
For this new research, the NC State researchers worked with researchers at the University of North Carolina. Your study, published last week in Vector-Borne and Zoonotic Diseases, compared 17 people with diagnosed schizophrenia or schizoaffectlive disorder to a control group of 13 healthy people, in what is known as a case-control study.
According to the study, both groups received a comprehensive exam. This included the use of more sensitive PCR tests, which look for the presence of pathogens in our body in DNA. Bartonella is something strange among bacteria, since they are capable of infecting and then hiding inside the cells of our body (red blood cells, in the case of Bartonella). This vanishing trick allows them to survive undetected by the immune system, and it also makes conventional tests for an active infection worse. Last year, Breitschwerdt and his colleagues published Research showing that this newer testing technique, called the digital drop test, or ddPCR, could be more accurate in identifying Bartonella than previous tests.
In 11 of the 17 people with schizophrenia or schizoaffective disorder, traces of Bartonella DNA could be found, while the same was true for only one of the 13 control patients. Although cats, dogs, and even the fleas they carry can be vectors for Bartonella transmission, the team found no link between an increased likelihood of infection and reported pet ownership or exposure to fleas.
The team is careful to describe their work as a pilot study, the sole aim of which is to show that this link is worth further investigation. But coupled with his previous research, Breitschwerdt believes that the case for this theory is only getting stronger.
“Our research to date continues to support a role for Bartonella species as a cause or cofactor in neuropsychiatric disease, ”Breitschwerdt told Gizmodo in an email.
However, he added: “There is a lot of work to be done to clarify these preliminary results.”
The team is already working to validate ddPCR tests for other groups of bacteria that can invade the bloodstream and may be more difficult to find with standard tests. With more funding and cooperation with other research centers, they also hope to conduct a larger study comparing people with and without schizophrenia.