Secondary diabetes mellitus may be caused by which of the following?

• A. Chronic steroids use
• B. Autoimmune beta cell destruction
• C. Excess insulin production
• D. Neonatal physiologic hyperglycemia

Answer: (A)

Secondary diabetes happens when an external factor or condition disrupts how the body handles glucose, rather than a primary autoimmune or genetic defect. Chronic glucocorticoid therapy fits this, because steroids raise blood glucose through multiple pathways: they increase hepatic glucose production (gluconeogenesis), decrease insulin sensitivity in muscle and fat, and promote protein and fat breakdown, all of which push glucose levels higher. With long-term use, this can develop into diabetes.

The other choices describe conditions not caused by a medication or external factor in this way. Autoimmune beta cell destruction is the classic mechanism of type 1 diabetes, a primary form, not a secondary effect. Excess insulin would tend to lower glucose, not cause diabetes. Neonatal physiologic hyperglycemia in newborns is usually transient and not a chronic diabetes cause.