At the age of two, Tiana Raposo started having up to 500 seizures every single day and nothing seemed to help keep the attacks under control.
The first time the Laval toddler's symptoms manifested was on Aug. 29, 2013. That's when her mother Linda Florio got a phone call from Tiana's daycare.
"She fell off the toilet and hit her head and she was a little bit not responsive," she said. "She ended up vomiting."
Until that day, Tiana behaved like any other child, her mom said.
On top of the seizures, during which her eyes would roll into the back of her head, Tiana would not speak, eat, or respond.
"It was a dark time, and I never thought we would come out of that period," Florio said. "I thought, this is our life now."
A promising diagnosis and unexpected treatment
During her seven months in hospital, Tiana underwent multiple medical treatments but nothing seemed to help.
After a week spent in the intensive care ward at the Montreal Children's Hospital, where Tiana was tested for a number of ailments including concussion and meningitis, her neurologist Dr. Bradley Osterman suggested the toddler could have a rare neurological disorder.
Anti-NDMA receptor encephalitis is an autoimmune disease that affects perception of reality, human interaction, the formation of memory and automatic functions, according to the Anti-NDMA Receptor Encephalitis Foundation.
"Dr. Osterman said 'everything she's doing, her epilepsy, her convulsions, the fact that she stopped talking and eating… I think it's encephalitis," Florio said.
"[Tiana's] immune system produced bad antibodies, which killed the right antibodies," said her father Jason Raposo.
After trying a number of medical treatments that failed to lessen the severity of the symptoms, Osterman told the family he wanted to try a new method: a very high-fat diet.
Through the ketogenic diet, the results were noticeable almost immediately — four weeks after Tiana changed her food intake, the number of seizures she was having per day diminished drastically.
And although Tiana, who is now six, still has some developmental delays, it's been a year and a half since she's had a convulsion.
"It changed our life. [Tiana] started talking and walking again, her eye contact improved, and she became more responsive," said Florio.
A medical first?
This is the first time this treatment method has been used to treat epileptic symptoms in a patient as young as Tiana, said Osterman.
"Looking at the literature, I am not aware of another case where [the ketogenic diet] has been tried, especially with this much success," he said.
For Osterman, improvement was visible right away.
"Her convulsions reduced quickly. We had more than a year without convulsions, with a return to a fairly normal development last year," Osterman said.
The neurologist is hopeful that Tiana will one day recover completely from the disease and catch up, despite her developmental delays.
"It's very encouraging to see how much [she] has recovered in the last year," he said.
High-fat diet treatment explained
Marie-Josée Trempe, Tiana's nutritionist, said the effect of nutrition on the body is underestimated by many.
"This diet has existed for a long time," Trempe said, adding that it was first used in the 1920s.
"Neurologists usually try medication first, and if it doesn't work, then they try diet."
First and foremost, Tiana's diet contains little to no carbohydrates — though some fruits and vegetables are allowed, and some foods high in protein.
Most of the time, though, Tiana is eating foods high in fat. That means grub like avocados, mayonnaise, and oil.
The ketogenic diet strictly moderates carbohydrate intake, replacing the majority of carb consumption with protein and fat.
While the breakdown varies, a typical ketogenic diet consists of fats providing 70 to 80 per cent of all calories, with proteins accounting for just about 10 to 20 percent, and carbs only five to 10 per cent.
"We don't know exactly how it works, but [the diet] forces the body to use fat as a source of energy instead of carbohydrates, and it creates ketones, which go to the brain, and seem to give good results," Trempe said.
Patients usually follow the diet for two years, then slowly wean off it, she added.
"It's temporary, that's why the younger they are, the better."