March 10, 2009 -- Lyme disease can't make a person violent or psychotic, infectious disease specialists tell WebMD.
According to media reports, the family and lawyer of a man accused of the murder of an Illinois pastor blame the man's deteriorating mental health on longstanding Lyme disease.
The experts who spoke with WebMD have not reviewed the man's medical records and are familiar with the case only through media reports. But speaking in general terms, the experts reject the idea that violent behavior can be blamed on Lyme disease.
"I don't know of any convincing evidence that Lyme disease can cause violence or psychosis," Gary Wormser, MD, tells WebMD. Wormser is director of the Lyme Disease Center and chief of infectious diseases at New York Medical College in Valhalla, N.Y.
"We can be clear Lyme disease does not lead to psychotic and violent behaviors," William Schaffner, MD, tells WebMD. Schaffner is president-elect of the National Foundation for Infectious Diseases and chair of preventive medicine and infectious diseases at Vanderbilt University in Nashville, Tenn.
In an August 2008 article -- written before the alleged attack by Terry J. Sedlacek -- the St. Louis Post-Dispatch chronicled the man's decade-long mental health problems. The article suggested his symptoms were due to Lyme disease.
But such "chronic" Lyme disease is "not a sound diagnosis" for anyone, Schaffner says. Untreated Lyme disease certainly can go on for a very long time. And Lyme disease damage doesn't necessarily go away with treatment. But Schaffner says there is little evidence that prolonged antibiotic therapy -- or other radical, unproven treatments -- benefits patients.
"The history I've gleaned from the news reports suggests this man was being treated for supposed chronic Lyme disease, a diagnosis that needs to be looked at with great skepticism," Schaffner says. "If this was a misfocused attention on Lyme disease, his real underlying problem was not given attention and therapy. Because Lyme disease, in whatever manifestation, does not lead to violent and psychotic behavior."
Wormser has actually looked for Lyme disease in Missouri, near the Illinois border where the man was supposed to have contracted the disease.
"In that part of Illinois, that this person lived in, it would be almost unheard of to have true Lyme disease," he says. "But so many people get misdiagnosed because of doctors sending samples to labs that give unreliable results. I would not be surprised if this individual were misdiagnosed."
But even if the man did have Lyme disease, the evidence suggests it could not have been responsible for his recent behavior.
Wormser actually tested psychiatric inpatients in his area, which is in the heart of the U.S. region most affected by Lyme disease. Patients suffering psychiatric illnesses were no more likely to have present or past Lyme disease than other area residents.
That's not to say that Lyme disease can't affect the brain. It can.
"Like most manifestations of this disease, neurological symptoms are hard to recognize and manage," Schaffner says. "You can have an encephalitis picture that almost always occurs with damage to one of the nerves to the face. This causes paralysis of part of the face. These are part of the later manifestations of Lyme disease."
"There is no question that Lyme disease has neurological manifestations," Wormser says. "But frank psychosis to the point of killing someone would be really far fetched. It is really clear they are dealing with a situation that probably wasn't Lyme disease to begin with."