New blood test could ease life for patients with rare form of diabetes
Fourteen-year-old Karine has received two insulin injections per day for as long as she can remember. Soon after birth she was diagnosed with juvenile-onset diabetes.
Fourteen-year-old Karine has received two insulin injections per day for as long as she can remember. Soon after birth she was diagnosed with juvenile-onset diabetes, also known as insulin-dependent or type I diabetes, which results in an inability to produce insulin. New testing at the Montreal Children's Hospital of the MUHC recently revealed that Karine has an extremely rare form of diabetes that responds to a class of drugs used to treat type II diabetes. This treatment switch has allowed Karine to stop insulin injections and has led to a significant improvement in her health.
"This form of diabetes starts very early in life and shares the same symptoms as regular type I diabetes," says Dr. Polychronakos, Director of Pediatric Endocrinology at the Montreal Children's Hospital of the MUHC and a professor in the Departments of Pediatrics and Human Genetics at McGill. "However, the causes are different so the disease responds to treatments that would not normally work for type I diabetes."
This new form of diabetes involves the mutation of a single gene, which can now be verified through a routine DNA test on a small sample of blood. "Earlier this year we began blood testing all our diabetic patients at the Children's," notes Dr. Polychronakos. "Karine was the only confirmed case of the 400 diabetics tested."
Switching from insulin injections to oral medication can result in significant health improvements. "Insulin injections are unpleasant, especially for a child, and often involve guesswork — it is difficult to determine exactly how much insulin to inject," says Dr. Polychronakos. "Since Karine switched to glyburide pills, her own pancreas has taken over and her blood sugar levels have shown marked improvement."
The MUHC is currently conducting research to see whether it would be advisable to test all early-onset diabetic patients for this mutation. "It is important to note that this form of diabetes is very rare," says Dr. Polychronakos. Only one case was discovered in the 400 patients tested at the Children's. "Despite the rarity, for the few diabetics that have this mutation, it can feel like winning the lottery," he notes.
Patients who wish to participate in research studies on the genetics of type I diabetes should contact Diane Laforte at the Montreal Children's Hospital at 514-412-4400 (ext. 22521).
The Montreal Children's Hospital is the pediatric teaching hospital of the McGill University Health Centre (MUHC). The institution is a leader in the care and treatment of sick infants, children and adolescents from across Quebec. The Montreal Children's Hospital provides a high level and broad scope of health care services, and provides ultra specialized care in many fields, including cardiology and cardiac surgery; neurology and neurosurgery, traumatology; genetic research; psychiatry and child development and musculoskeletal conditions, including orthopedics and rheumatology. Fully bilingual and multicultural, the institution respectfully serves an increasingly diverse community in more than 50 languages.
The McGill University Health Centre (MUHC) is a comprehensive academic health institution with an international reputation for excellence in clinical programs, research and teaching. The MUHC is a merger of five teaching hospitals affiliated with the Faculty of Medicine at McGill University — the Montreal Children's, Montreal General, Royal Victoria, and Montreal Neurological Hospitals, as well as the Montreal Chest Institute. Building on the tradition of medical leadership of the founding hospitals, the goal of the MUHC is to provide patient care based on the most advanced knowledge in the health care field, and to contribute to the development of new knowledge.