A teenager was left believing he was an evil, damned son of the devil after he caught a mind-altering bug from a cat.
The 14-year-old suffered hallucinations, violent outbursts and thought about killing his family after he was scratched by his pet.
He was initially diagnosed with rapid onset schizophrenia and his mother had to quit work to care for the otherwise healthy boy.
However, further tests recognised it as the rare bug bartonella henselae which he had caught from his cat.
The case came to light after researchers documented it in the Journal of Central Nervous Disease.
Dr Ed Breitschwedt, lead author of the case report, said: This case is interesting for a number of reasons.
Beyond suggesting that infection itself could contribute to… schizophrenia, it raises the question of how often infection may be involved with psychiatric disorders generally.
The unnamed teen was hospitalised four times in 18 months exhibiting severe psychiatric symptoms.
He was also plagued by painful headaches, chest pains, shortness of breath and a constant urge to urinate.
He had to miss school for two years because his delusions meant that he refused to leave the house.
During his last visit to the hospital in North Carolina, one medic noticed that the boy had a series of lesions on his skin around the armpit and thigh.
It was recognised as a sign of bartonella henselae and tests confirmed he had caught the infection.
Bartonella is a bacteria that is most commonly associated with cat scratch disease and until recently was thought to be short-lived.
There are around 30 different species of bartonella and the bug is notorious for hiding in the lining of blood vessels.
The boy in the case was treated with antimicrobial chemotherapy and has since made a full recovery.
Medical advice for dealing with a cat bite includes cleaning the wound with warm water and encouraging it to bleed slightly.
Any dirt or foreign objects should be removed. For severe wounds, seek medical treatment.