Porter had complained of a sore throat on November 7 and it developed into a fever of 102 degrees by November 12, according to the coroner.
Porter's death shook the hip-hop community, one so deeply engrained in her life as the long time girlfriend of Combs.
She was buried in her hometown of Columbus, Georgia, during a public funeral held by Combs.
She was found dead in her home in the Toluca Lake neighborhood last November.
Fans are finally learning the real reason behind the shocking death of Kim Porter, the former girlfriend of music mogul Sean "Diddy" Combs. She was laid to rest near her mother, Sarah Porter, who died in 2014 after a bout with cancer.
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"For the last three days I've been trying to wake up out of this nightmare", Combs wrote in an Instagram tribute to Porter after her death. She apparently contacted her doctor the day before her death complaining that she wasn't getting better. She was 47 years old.
"I just want to say to my kids, Justin, Christian, D'Lila, Jessie, Chance and the other man in the house, Quincy: Your mother instilled in me this, and I pledge in front of everybody right now that I will always be there for you", Combs said, TMZ reported. But I haven't. I don't know what I'm going to do without you baby. You have no idea how much it means to us.
Diddy, 49, and Porter began dating in 1994. The insider added, "They were still a family". The pair shared three children together including son Christian Casey Combs, now 20, and 11-year-old twin daughters Jessie James Combs and D'Lila Star Combs.
The Epoch Times reporter Jack Phillips contributed to the report.