On an otherwise routine Tuesday evening in February, 11-year-old Nupur Mate was complaining at home about a headache.

The Mississauga girl had a 39 C fever and her symptoms seemed to be those of a common cold or influenza. But when Nupur couldn't stop shivering, her family took her to the emergency room at nearby Trillium Hospital.

That hospital visit became the first of two times her parents were told their daughter had influenza and could recover at home.

The third time Nupur's parents took her to the hospital, her heart stopped, and she had to be resuscitated.

Nupur has since had two limbs amputated — her left arm and right leg — and is surviving on dialysis at the Hospital for Sick Children, following a diagnosis of a serious bacterial infection caused by streptococcus A. Her family is now questioning why Trillium Hospital doctors didn't pick up on the severity of Nupur's symptoms sooner.

"One day, fever — OK. But three days, plus the pain … you don't just say 'oh, it's flu,'" her mother Sunita told CBC Toronto.

Doctors all thought flu

Sunita said her daughter rarely gets sick. This time was different.

Initially, the family's doctor advised rest and Tylenol to keep Nupur's fever down.

Then, when the family went to Trillium on Feb. 21, they waited four hours to see a doctor, Sunita said, adding that nurses were dismissing her concerns that her daughter had something worse than the flu. Frustrated, Sunita and Nupur went home to rest instead.

The next morning, Nupur woke up wincing with severe pain in her left arm and right leg, so they again rushed her to the emergency room.

This time, she had blood work and X-rays. They all came back clear.

"Everything points to influenza B," Sunita recalled the doctor saying, but that diagnosis didn't sit right with her.

"As far as I know, flu meant whole body pains, not in a particular part," she said.

In a life-saving measure to stop the infection, her left arm and right leg were eventually amputated. (Submitted/Sunita Mate)

Not flu, but a serious infection

It turned out a bacterial infection was attacking Nupur's body at a rapid pace. By Friday, her hands and feet felt cold to the touch.

"As a mom, I was doing all that I can. I put socks on her, I was rubbing her hands. After one hour, she said she doesn't have any feeling — she was completely numb," Sunita recalled.

Sunita called 911 that evening.

Nupur's blood pressure was plummeting in the ambulance back to Trillium, her mom said. "She was so pale. It was the first time I felt I was losing my daughter," Sunita said.

'I heard a nurse say, 'She's dead.'" - Nupur Mate's mother, Sunita

Soon after arriving, Nupur's heart stopped. "I heard a nurse say, 'She's dead,' then everyone, doctors and nurses, rushed over."

Sunita says 10 to 15 doctors took turns performing cardiopulmonary resuscitation on her daughter.

Nupur stabilized and was taken to SickKids. Her body was pumped with antibiotics to stop the infection from attacking more of her insides, Sunita said.

While on life support for more than a week, and 17 days spent in the ICU at SickKids, blood culture tests finally revealed the real diagnosis: Nupur had a bacterial infection caused by streptococcus A.

The next revelation was that they had to amputate to stop it from spreading, and there was no saving the limbs Nupur had been complaining about: Physicians had to cut her left arm above the elbow and her right leg partially below the knee, her mom recalled.

Nupur's mother Sunita Mate says her daughter rarely got sick. (Submitted/Sunita Mate)

Dr. Alison McGeer, infectious disease consultant at Mount Sinai hospital, says Nupur's bacterial infection is extremely rare — and that her case is an anomaly.

"Most often, streptococcus A will live in the nose and throat of people, and nothing will come of it," said McGeer, who is not involved in the family's health care.

She added it's a one-in-a-million instance for strep A to cause septic shock as it did in this case. There is also no vaccine to prevent a streptococcus A infection — and no way to tell who can fight the infection and who cannot.

"The tragedy is that for two or three days this condition just looks like a regular viral illness," McGeer said. "And then all of the sudden, this very serious illness develops."

Nupur Mate was soon going to reach her brown belt in her beloved karate classes. (Submitted/Sunita Mate)

Sunita said when her daughter woke up to her missing arm and leg, she asked, "How did this happen? I only had a cough."

While Nupur's family is questioning why the infection wasn't discovered sooner, McGeer said the doctors could not have predicted Mate's condition would advance the way it did.

In a statement provided to CBC Toronto, Trillium Health Partners said they would not comment on the case due to patient confidentiality.

"When a patient presents at one of our emergency departments, they are assessed and triaged based on their current medical needs," the statement said.

Attacked everything but her spirit

After 17 days in the intensive care unit, Nupur is still at SickKids spending hours on dialysis as her kidneys heal.

Sunita has quit her job to be by her daughter's side during her recovery. It isn't clear when she will be well enough to go home, and her family has launched a Go Fund Me campaign to raise money to relieve some of the financial burden of Nupur's recovery. ​

Nupur's heart stopped on her third visit to Trillium Hospital. After doctors stabilized her, Nupur was taken to SickKids, where she spent more than a week on life support. (Submitted/Sunita Mate)

Once her kidneys stabilize, her long journey in rehabilitation with prosthetics will begin. Nupur always loved swimming lessons and karate classes, her mom said, and Sunita said she's told her everything she wanted to do, she still can.

"It attacked everything in her body but her spirit," she said.