I have read so many times about adults being diagnosed with T2D when they are actually have T1D. Here is a quote from a very good article on this topic.
"People with adult-onset Type 1 diabetes/LADA who are misdiagnosed as having Type 2 diabetes are wrongly treated as though they have Type 2 diabetes. Consistent evidence shows the importance, in terms of clinical outcome, of early initiation of insulin therapy in Type 1/LADA. Thus, the early clinical recognition of people with adult-onset Type 1 diabetes, as distinct from Type 2 diabetes, is extremely important to guarantee the most suitable treatment in order to preserve beta-cell function, gain optimal metabolic control, and improve long-term outcomes. A correct diabetes diagnosis is the cornerstone of correct therapy and a wrong diagnosis delays achievement of optimal metabolic control, frustrates patents, and increases the risk of life-changing or fatal complications."
The link for the complete article appears below: