Autumn M. Klein, 41, who was the chief of the division of women's neurology at the University of Pittsburgh Medical Center, died April 20 after she collapsed in her home the same day, the Pittsburgh Post-Gazette reported Thursday.
High levels of cyanide were found in her system.
"Our homicide unit is investigating the death of a female UPMC employee, where she was found at the time of her death with toxic levels of cyanide in her system," Pittsburgh police major crimes Lt. Kevin Kraus said.
Kraus did not give any more details on the investigation.
The Allegheny County medical examiner's office said it was waiting for the results of toxicology and neuropathology tests, which may take 12 to 16 weeks, to determine Klein's cause of death.