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  #1  
Old 10-20-2011
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A 26-year-old man is brought to the emergency department after being found by his family on his bathroom floor. He had apparently collapsed after being increasingly ill. His mother reports that over the last several weeks he has had severe insomnia, tremors, diarrhea, and fatigue. On arrival is only vaguely interactive and he does not follow commands appropriately. His blood pressure is 143/89, pulse is 125/min and his oxygen saturation is 96% on room air. On examination, he is diaphoretic and has a wide-eyed stare. He has a 2/6-midsystolic murmur at the second left intercostal space. His deep tendon reflexes are brisk throughout. Laboratory studies show:


Which of the following is the most appropriate next test to establish the etiology of this patient's collapse?



A.

24-hour urine for total catecholamines


B.

CT scan of the head


C.

Radioactive iodine uptake scan of the thyroid


D.

Serum thyrotropin-releasing hormone (TRH)


E.

Serum free triiodothyronine (T3) level








The correct answer is E. This patient is suffering from a severe bout of thyrotoxicosis, which is confirmed by his undetectable level of TSH. The surprising aspect of his presentation is the normal serum free T4. The most common causes of hyperthyroidism, Graves' disease and toxic multinodular goiter, both result in greatly increased production of T4. However, they can often have a proportionately greater increase in T3. Increased peripheral conversion of T4 to T3 may also play a role. In this patient's case, a solitary hyperfunctioning thyroid adenoma is secreting mostly T3, which is much more potent on target tissues than is T4. This condition, called T3 thyrotoxicosis, often occurs in the initial stages of hyperthyroidism, when symptoms are mild. However, it can also produce florid symptoms such as those seen above. The most appropriate next test to establish the etiology of this patient's collapse is the serum free T3 level.
A 24-hour urine for total catecholamines (choice A) is an appropriate initial test to screen for pheochromocytoma. Patients with these small, active tumors can present with tachycardia, mental status changes, and autonomic hyperactivity. However, their serum TSH levels will be normal, unlike this patient. The presence of a depressed TSH in the presence of hyperthyroid-like symptoms should always make the clinician suspect thyroid disease first.
A CT scan of the head (choice B), might be an appropriate study given his mental status changes. However, given what we know about the course of his illness and his laboratory results, imaging is unlikely to provide additional diagnostic information.
Radioactive iodine uptake scan of the thyroid (choice C), is a common test to evaluate the cause of hyperthyroidism. However, it often adds little to the history and physical examination and only serves to determine the appropriate dose for radioiodine ablation of the thyroid. For example, patients with Graves' disease will often have a family history of thyroid disease and will have a diffusely enlarged goiter. Patients with a solitary hyperfunctioning adenoma and such florid symptoms will invariably have a palpable nodule on physical examination. In this patient's case, the blood test is required first to confirm the diagnosis, and time cannot be spared to wait for a test as cumbersome as a thyroid uptake scan.
Serum TRH level (choice D), is rarely, if ever, useful in the evaluation of thyroid disease. The combined use of TSH, T4, and T3 studies makes this assay unnecessary, even when evaluating for "tertiary" or hypothalamic hyperthyroidism.


A 20-year-old woman with insulin-dependent diabetes comes to the office for a scheduled followup appointment. She was diagnosed with diabetes at age 5 years and has managed her illness very effectively. She has never had diabetic ketoacidosis or hypoglycemic episodes. She denies fever, chills, weight loss, polyuria, or excessive thirst. She has no other medical issues. Her medications include NPH, 20 units twice daily and regular insulin, 5 units before each meal. Review of her blood glucose record indicates that blood glucose levels are routinely 120-150 mg/dL before breakfast, dinner, and bedtime, with the normal being 116 mg/dL. Which of the following is the next most appropriate step in management?



A.

Decrease the dosage of NPH


B.

Decrease the dosage of regular insulin


C.

Increase the dosage of NPH


D.

Increase the dosage of regular insulin


E.

Make no changes and obtain a hemoglobin A1C
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  #2  
Old 10-20-2011
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First one was already answered and as for the second one im not really sure about

her normal glucose lvls are good but the lvl BEFORE meals seem a little on the high side (120-150) so this might need some adjustment of her NPH insulin dosage.

at the same time her HbA1c would give a better picture of her overall glycemic control

so im not really sure but still il go with increase her NPH dose.
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Old 10-20-2011
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the dose of insulin insufficient for 12 hrs (NPH) ,due to its low dosage the anti glycemic control is not effective till 12 hrs..so we need to increase the dose
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Default Answer

The correct answer is E. The patient has very good glycemic control. She may be experiencing higher levels with snacks, however. Her near perfect sugar levels should be confirmed objectively by checking a hemoglobin A1C level, which is an average glucose level over the past 3 months.
Decreasing the NPH dosage (choice A) might increase sugar levels 4-6 hours later.
Decreasing the dosage of regular insulin (choice B) would lead to an increase in sugar levels 30 minutes later.
Increasing the NPH dosage (choice C) would decrease sugar levels 4-6 hours later.
Increasing the regular dosage would decrease sugar levels 30 minutes later (choice D).
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Old 10-21-2011
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Please correct me if im wrong NPH insulin is given to provide a steady basal state. While the regular insulin given before meals is to control the post prandial hyperglycemia. If we increase the NPH wouldnt that decrease the glucose lvls we see before meals (since that is the basal glucose lvl )?

When i was reading the question i was thinking long term daily control and since it was slightly high and the fact she was DM1 i personaly would like tighter glycemic control.
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