WBR0919

Author	PageAuthor::Vendhan Ramanujam
Exam Type	ExamType::USMLE Step 3
Main Category	MainCategory::Community Medical Health Center, MainCategory::Primary Care Office, MainCategory::Inpatient Facilities
Sub Category	SubCategory::Endocrine
Prompt	[[Prompt::A 26 year old Caucasian male comes to his physicians office for his regular checkup. He is a known type 1 diabetes mellitus patient for the past four years who was on NPH insulin, 30 U each morning and 15 U every night. But following a persistent morning glycosuria that did not improve, the evening dose was increased to 20 U during his last visit. He strictly adheres to his diet schedule. His following lab tests reveal worsening of his morning glycosuria with moderate ketones in his urine. Several consecutive nights glucose monitoring did not reveal any hypoglycemia. He is diagnosed with hyperglycemia due to reduced sensitivity to insulin and increase in early morning catabolic hormones called as dawn phenomenon. The evening dose of NPH is switched over to glargine. But neither did this help. What will be the next step in management of this patient]]
Answer A	AnswerA::Increasing the evening dose of NPH insulin further
Answer A Explanation	AnswerAExp::'''Incorrect'''-Increasing the evening dose of NPH insulin further might not be helpful since a previous attempt did not turn improve the patients condition.
Answer B	AnswerB::Administering glargine as late as possible during evening
Answer B Explanation	AnswerBExp::'''Incorrect'''-The onset of action of glargine is 3 to 4 hours and its duration of action is 22 to 24 hours. So administering it as late as possible during the evening will not be useful.
Answer C	AnswerC::Increasing the morning dose of NPH insulin
Answer C Explanation	AnswerCExp::'''Incorrect'''-Only increasing the evening dose of insulin will be helpful in treating Dawn phenomenon and not the morning dose.
Answer D	AnswerD::Advising the patient not to eat late in the night
Answer D Explanation	AnswerDExp::'''Incorrect'''-The patient already adheres to his strict diet schedule, which will include avoidance of late night eating.
Answer E	AnswerE::Add metformin
Answer E Explanation	[[AnswerEExp::Correct-After confirming the dawn phenomenon, if the patient is not responding to adjusted dosage of evening medication (increased evening NPH insulin dose) and switching over to a longer acting insulin (glargine) during the evening, adding metformin will be the next best step in management since metformin inhibits liver glucose production.]]
Right Answer	RightAnswer::E
Explanation	[[Explanation::Early morning hyperglycemia without nocturnal hypoglycemia in diabetes mellitus patients who are on insulin is called as Dawn phenomenon. This is due to the increased body production of certain hormones (growth hormone, cortisol, catecholamines, glucagon and epinephrine) between 4 a.m. and 8 a.m., which suppress the activity of insulin and trigger the glucose release from liver. In non-diabetic people, the body responds to the excess glucose that accumulates as a result of this process by producing insulin. The insulin then moves the excess glucose into the cells. However, people with diabetes either fail to produce insulin or cannot properly use the insulin that is available. As a result, glucose continues to rise to abnormally high levels (hyperglycemia). The first step will be to monitor nocturnal blood glucose on several consecutive days, to rule out hypoglycemia that occurs due to Somogyi effect. After confirming, the next step in managing Dawn phenomenon will depend on the case. When the patient is not responding to adjusted dosage of evening medication (increased evening NPH insulin dose), the next best step will be to switching over to a longer acting insulin (glargine) during the evening. If switching over to a longer acting insulin (glargine) did not help, adding metformin will be the next best step in management since metformin inhibits liver glucose production. Educational Objective: Early morning hyperglycemia without nocturnal hypoglycemia in diabetes mellitus patients who are on insulin is called as Dawn phenomenon. The first step will be to rule out Somogyi effect by monitoring nocturnal blood glucose levels. The following management like adjusting the pre-bedtime diet, exercise plan, oral medication or insulin therapy will depend upon the case. Adjusting medication dosage: Physicians may recommend that patients take more medication in the evening or schedule their dosages of long-acting insulin later in the evening so peak action occurs when glucose starts rising. Eating a snack before bedtime: Some patients may be advised not to eat late at night. However, some cases of dawn phenomenon are a response to lower glucose that occurred earlier. Their physicians may advise such patients to smooth these glucose roller coasters by eating a snack before bedtime. They may recommend a small snack that contains protein or fat and is low in carbohydrates, such as nuts or cheese. Exercising earlier in the day: Strenuous physical activity at night can cause lows at night, which may trigger rebound highs. Taking metformin: This oral medication curbs glucose production by the liver, and has been used effectively to treat people with dawn phenomenon if adjustment of evening doses fail. Educational Objective: References: ]]
Approved	Approved::Yes
Keyword	WBRKeyword::Dawn phenomenon
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::