Misdiagnosis

Dan explains in the video how getting a genetic diagnosis and coming off insulin changed his life.

Around 80% of patients with monogenic diabetes are initially misdiagnosed as having type 1 or type 2 diabetes. This is usually a consequence of unfamiliarity with monogenic diabetes. For example, a diagnosis of type 1 diabetes may be made in a young person where the family history of diabetes is not considered relevant or a diagnosis of type 2 diabetes may be made in a patient who is older or overweight. Taking a thorough family history noting particularly ages of diagnosis, treatment and BMI can help identify those families with autosomal dominant inheritance which would be worth investigating further.

Misdiagnosis can impact on treatment with patients taking unnecessary insulin injections or tablets which are sub-optimal for the subtype of MODY or patients with Glucokinase MODY being given treatment which is not needed at all. In the UK there is a national network of Genetic Diabetes Nurses who raise awareness of monogenic diabetes and discuss local cases. They are also trained in supporting patients through genetic testing and treatment change. Some patients who have previously been told they have ‘type 1’ diabetes find it initially hard to adjust to a life without insulin injections and need support in transferring to tablets.

Misdiagnosis can also impact on advice regarding the risk of other family members developing diabetes. If an individual has a monogenic cause of diabetes, the risk to their children of inheriting the same genetic change and developing diabetes is 1 in 2, or 50%, in contrast to around a 30% lifetime risk to children of a parent with type 2 diabetes or 2-6% to children of a parent with type 1 diabetes.