Advanced treatments control Cape Breton girl’s complex immune disorder

Catherine LeBlanc and her parents, Lynn and André, of Petit de Grat, Nova Scotia, were preparing for a much-anticipated trip to Disney World when they ended up taking an unanticipated trip to the IWK Health Centre.

“Catherine was falling—she fell at Walmart and then again at the airport hotel,” recalls Lynn of that day in May 2011. “At first we thought she was just tripping over her new shoes, but then we noticed that one of her knees was massively swollen, so we took her to emergency.”

X-rays and bloodwork revealed nothing—no fractures, no obvious disease. Suggesting that it might be arthritis and should be followed up upon their return, the doctor recommended ibuprofen and gave the family his blessing to go ahead with their Disney vacation.

“We had a wonderful time, but on the way home, Catherine fell again,” says Lynn. “Fortunately, it didn’t take us long to see a rheumatologist at the IWK.” Dr. Elizabeth Stringer diagnosed juvenile arthritis and prescribed Naprosyn—but within days, the then four-year-old Catherine was in crisis. “She was vomiting, her lips were white, and her skin and corners of her eyes were yellow.” Local doctors were so concerned, they arranged for Catherine to be airlifted to the IWK.

New investigations at the hospital revealed that, not only did Catherine have juvenile arthritis, she also had autoimmune anaemia, caused by an underlying immune dysregulation disorder, known as CVID (common variable immune deficiency). As the name suggests, CVID varies—in Catherine’s case, her immune system was generating inflammation in her joints (later also in her eyes), while rapidly destroying her red blood cells. Ten blood transfusions and large doses of steroids stabilized her short term, but the team soon realized Catherine’s immune system needed a reboot with chemotherapy.

Immunologists Drs. Andrew Issekutz, Thomas Issekutz and Beata Derfalvi monitored Catherine’s immune system on an ongoing basis, using a sophisticated cell-sorting and analysis machine called a flow cytometer. They discovered that, in addition to an overabundance of B-cells, Catherine lacked protective antibodies. When it became clear she was not developing a normal immune system following the chemotherapy, they moved on to intravenous immunoglobulin replacement (IVIG) therapy.

Even though Lynn is a nurse, André took on the challenge of learning to administer the immunoglobulin at home, weekly. “We didn’t want Catherine to have to go to the hospital more than absolutely ecessary,” André says. “Getting the treatment at home helped with her anxiety, which was really high because of all the needles she’d already received.”

Catherine is now treated by a multidisciplinary team at the IWK, including a rheumatologist, ophthalmologist and immunologist. While the IVIG helped boost Catherine’s immune system against bacteria and viruses, as well as reduce inflammation, she needed other medications to tone down her immune system and stop it from attacking her joints, eyes and red blood cells. Her rheumatologist

prescribed a targeted biologic treatment that blocks inflammatory messenger molecules, which Catherine

receives every two weeks. More recently, she added another immunosuppressive medicine targeted especially to the arthritis-related inflammation in Catherine’s eyes. “These will be lifelong treatments for Catherine, unless or until better options come along,” says André. “We just hope research will lead to less-invasive treatments, so she doesn’t have to have so many needles—or, better yet, a cure that would stop or reverse the disease.”

Now nine years old, Catherine is a positive, kindhearted and empathetic child who loves animals and being active outdoors. She and her parents are happy to be supporting Dalhousie Medical Research Foundation’s 2016-17 Molly Appeal, which is raising funds for inflammation, infection and immunity research. A large portion of the funds will go to purchasing a powerful new flow cytometer. This will allow researchers at Dalhousie Medical School and the IWK to perform more complex, in-depth analyses of the immune system and identify potential new strategies for treating immunity-related disorders and diseases.