What are the physiologic mechanisms involved with the polydipsia, polyuria, and polyphagia in diabetes mellitus?

D.K. is an 18-year-old high school student who began to experience weight loss despite a ravenous appetite and resulting increased dietary intake. She has
to make frequent trips to the bathroom to urinate and has difficulty concentrating on her work because of fatigue. She drinks large volumes of coffee to
help with a constant dry mouth and to combat her fatigue. At a clinic appointment, it was noted that D.K.’s weight has dropped from 140 to 128 pounds. She
is 5 feet 7 inches tall. Her urine specimen shows glycosuria and ketonuria. A chemstick blood glucose level is 412 mg/dl. D.K. had eaten breakfast 3 hours
before the chemstick blood test.

Discussion Questions

1. Considering D.K.’s presenting history and physical data, what form of diabetes mellitus is indicated?

2. What are the physiologic mechanisms involved with the polydipsia, polyuria, and polyphagia in diabetes mellitus?

3. What immediate and long-term therapy will D.K. need to manage her disorder?