Can you have diabetes insipidus with normal blood sodium levels ?

Anything is possible since it depends on what the sodium level is at baseline. If there is an abnormal sodium level at baseline, the diabetes insipidus could normalize it. Typically the sodium level increases with diabetes insipidus because there is dehydration associated with the disorder. If it is caught early, the sodium level may also be normal. Good luck!

This is extremely rare but possible if the blood sodium levels were affected by depletion from some cause eg fluids.