Final answer:
Polyuria, or excessive urination, is a symptom of hyperglycemia in diabetes mellitus. High blood glucose levels make it difficult for the kidneys to recover all the glucose from urine, causing glucose to be lost in urine. Increased thirst and increased hunger may also be present in hyperglycemia.
Step-by-step explanation:
A nurse monitoring a client newly diagnosed with diabetes mellitus should look for signs of hyperglycemia. One of the signs that would indicate hyperglycemia and warrant health care provider notification is polyuria, which refers to excessive urination. This occurs because high blood glucose levels make it difficult for the kidneys to recover all the glucose from urine, resulting in glucose being lost in urine. Other symptoms of hyperglycemia may include increased thirst and increased hunger.