Cause of Death Revealed for 17-Year-Old Rugby Star Who Collapsed Days After Being Sent Home from Hospital

The cause of death has reportedly been revealed for a 17-year-old rugby player in the U.K. who collapsed days after first going to the hospital earlier this year.

During a recent inquest into the death of Lilly Day, which was held at Cheshire Coroner’s Court in England, it was confirmed that the teenager died from a ruptured spleen after suffering “a rare complication” from a common virus, according to the Warrington Guardian.

Lilly had attended an appointment at her doctor’s office in Warrington, Cheshire, on Feb. 14.

She died four days later, according to online records.

After attending her doctor’s appointment, Lilly was diagnosed with a viral upper respiratory tract infection, the Warrington Guardian reported. However, she didn’t get any better and went to the hospital the following evening, on Feb. 15, around 8:30 p.m. local time — complaining of a cough, sore throat and nasal congestion.

According to the inquest, Lilly — who previously played for teams including the Warrington Wolves Women’s Super League and was reportedly being eyed by both England and Ireland’s national teams — also had puffy eyes and swelling in her neck.

Medics thought a change in environment might have played a factor in her illness, the Guardian reported, so the teen — who had only started to feel unwell in January — was told to look into allergy testing.

Lilly continued to feel ill, experiencing symptoms including nausea and diarrhea, before collapsing in her bathroom at her home on Feb. 18, according to the Guardian. She remained conscious on her way to the hospital but was tired and experiencing pins and needles.

After arriving at the hospital, Lilly lost consciousness after having her blood taken before going into cardiac arrest.

She was pronounced dead within hours, according to the Guardian.

A post-mortem examination confirmed Lilly died from a ruptured spleen, which was caused by glandular fever, the Guardian reported, adding that she’d suffered “a rare complication” from the viral infection.

The U.S. term for glandular fever is infectious mononucleosis (mono), which is spread through saliva, according the Mayo Clinic.

Mono is often called the kissing disease and though it can be spread through kissing, people “can also be exposed by sharing a glass or food utensils with someone who has mono,” according to the medical center.

The senior coroner for Cheshire, Jacqueline Devonish, said at the hearing that Lilly’s spleen didn’t rupture until the morning of her death, so there was nothing that could have previously alerted medics, according to the Guardian.

Her cause of death was listed “as hypovolemic shock due to intra-abdominal haemorrhage, severe splenomegaly with rupture, and Epstein-Barr virus induced infectious mononucleosis,” the newspaper reported.

The Warrington Girls Community Rugby League Club, which Lilly previously played for, was among many paying tribute to the teen following her death. 

The team set up a GoFundMe to raise money for Lilly’s family, writing in a description, “Words cannot express the depth of our sorrow. We are heartbroken for Lilly’s family and offer them our deepest condolences during this incredibly difficult time. We also extend our love and support to her many friends and teammates who are struggling with this loss.”

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During the court hearing, Lilly’s mom, Dawn Boadey, said she “loved life. She had … many friends. She was happy to go out. She worked hard and played hard,” the Guardian reported.

“I don’t know a person that didn’t like Lilly,” Boadey said.

The Cheshire Coroner’s Office did not immediately respond when contacted by PEOPLE for further comment.