An accomplished and well-respected Pennsylvania doctor who suddenly collapsed in her home had "toxic levels of cyanide" in her bloodstream, according to police.
Autumn Marie Klein, 41, collapsed at her Oakland, Pa., home and died on April 20 at UPMC Presbyterian, where she was chief of the division of women's neurology and an assistant professor of neurology, obstetrics and gynecology.
The medical examiner has not determined an official cause of death, but police are saying she had high levels of cyanide in her blood. Cyanide is "a rapidly acting, potentially deadly chemical that can exist in various forms," as defined by the Center for Disease Control and Prevention.
"Our homicide division is conducting a death investigation of a female UPMC member where she was found at the time of her death with toxic levels of cyanide in her bloodstream and we're continuing to work with the medical examiner's office to determine the definite cause and manner of her death," Lt. Kevin Kraus of the Pittsburgh Police Department told ABCNews.com.
Kraus said he could not comment on the interviewing of any witnesses because the investigation is ongoing.
When asked if the case has been classified as suspicious, Kraus said, "Not at this point."
Klein was married to Robert Ferrante and had a daughter named Cianna, who is 6.
Klein's mother, Cook Klein, 79, lives in Towson, Md., and could not imagine anyone wanting to hurt her daughter.
"I don't know of anybody that would have a reason to try to hurt her," she said. "I wouldn't think so though because of the type of person she was."
"She was just a wonderful human being and a fantastic mother," an emotional Cook Klein said. "She was a person that cared for everybody. She was an absolutely wonderful mom. There was nothing about her that anybody would not like."
Cook Klein said her humble daughter was not one to talk much about her many accomplishments, but had been passionate about science from a young age.
"She always considered herself a geek that had her nose in a book," she said. "She was interested since the seventh grade in biology class. She knew from then on what she wanted to do and she was just great at what she did."
Cook Klein said her daughter had been selected by the American Academy of Neurology as one of the 10 most promising neurologists in the country and that three people at the funeral home told Cook Klein that they were working on publications with Klein. The three had traveled from Ohio, Florida and Canada to be at the funeral.
When Cook Klein got word of her daughter's death she and her husband were preparing to travel to Pennsylvania to babysit the daughter while the parents went out of town for a medical event. Cook Klein was packing her suitcase late the night before she was set to leave when she said Ferrante called her.
"Bob was saying something had happened to Autumn and he was there in the house by himself with Cianna," Cook Klein said. "He had called 911 and they had taken Autumn to the emergency room."
Cook Klein said she was initially told her daughter may have suffered a stroke.
When she heard about the cyanide, her first concern was her granddaughter and who would pick her up from school if police needed to speak to her father. Cook Klein said police told her that Cianna was with her father.
She said her young granddaughter "just knows her mommy isn't home."
Klein's husband Robert Ferrante could not be reached for comment.