Sheriff: Wis. toddler likely died from hyperthermia

Isaiah Theis
Isaiah Theis of Centuria, Wis., was found dead in a car trunk.
Photo courtesy Polk County Sheriff's office

A toddler found dead in the trunk of a car near his Wisconsin home probably died of hyperthermia -- high body temperature -- during one of the hottest days of the summer, authorities said today.

The body of 2-year-old Isaiah Theis, of Centuria, Wis., was found late Wednesday in the trunk of a car near his parents' home. Searchers thought it had been secured before he went missing and didn't look inside until the owner came to retrieve the vehicle from the Theis family's home. A sheriff's deputy checked the trunk and found the boy, who had been missing since Tuesday night. He was dead.

A preliminary autopsy concluded the boy died of hyperthermia, the Polk County Sheriff's Office said.

Hyperthermia is the opposite of hypothermia. It's an "abnormally high body temperature caused by a failure of the heat-regulating mechanisms of the body to deal with the heat coming from the environment," according to the National Institutes of Health.

Polk County Sheriff Pete Thompson said in a release today that the boy showed no signs of trauma or other disease during the autopsy. The case remains under investigation.

More than 2,400 volunteers had searched for the boy.

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