An atypical presentation of type 1 diabetes

Type 1 and type 2 diabetes have been described historically as occurring in distinct patient populations; however, atypical demographics are becoming more frequent as the prevalence of diabetes increases, crossing boundaries of ages. Some of these cases can be challenging to diagnose clinically as the patient symptomatology and progression can differ from the standard features of type 1 and 2 diabetes. Our case is an example of a patient whose type 1 diabetes presented atypically with characteristics often associated with type 2 diabetes. Patient presentations such as this are uncommon, with our patient having presented with the “textbook” characteristics of type 2 diabetes. When first diagnosed with diabetes mellitus type 2, the patient was 60 years old, had a BMI around 30 and experienced a gradual onset of symptoms over the course of several months. At the age of 64, the patient tested positive for GAD65 autoantibodies following a year of declining glycemic control and was re-evaluated and classified as a type 1 diabetes patient. Subsequent insulin injections resolved his diabetes-related complications which included polyuria, weakness and weight loss and improved his glycemic control. This case provides an example of an unusual clinical presentation of type 1 diabetes and serves to raise awareness for atypical presentations of diabetes to improve accurate classifications at earlier stages.