Laboratory values are as follows:?

Question

18: A 55-year-old woman who has a history of severe depression and who had radical mastectomy for carcinoma of the breast 1 year previously develops polyuria, nocturia, and excessive thirst. Laboratory values are as follows:

Serum electrolytes: Na- 149 meq/L; K- 3.6 meq/L
Serum calcium: 9.5 mg/dL
Blood glucose: 110 mg/dL
Blood urea nitrogen: 30 mg/dL
Urine osmolality: 150 mOsm/kg
The most likely diagnosis is:
a. Psychogenic polydipsia
b. Renal glycosuria
c. Hypercalciuria
d. Diabetes insipidus
e. Inappropriate antidiuretic hormone syndrome

Answer 1

D, Diabetes insipidus. This involves vasopressin, which include vasopressin receptors found in the breast and in the kidney. Desmopressin is usually given to correct this problem and allow the person to retain water and return their electrolytes back to normal. In this case, the only lab values that aren't normal are the urine osmolality (low), BUN (high), Sodium (very high), and the Potassium is kind of low. Also, nocturia is a classical sign of neurogenic diabetes insipidus. One might think this could be hypercalciuria, but the calcium levels in this person are fine, indicating that diabetes insipidus would be the right diagnosis.

What are you in school for? Apparently you are doing the section on diabetes? :)

Answer 2

OK...

This patient has polyuria, nocturia, and excessive thirst.
In spite of this, she has a high serum sodium, an elevated urea nitrogen, and an unconcentrated urine (<200mOsm/kg).

This is consitent with d. DI.

Choice a. and choice e. are typically associated with low serum sodium.

Choice b. is unlikely in view of the low urine osmolality.

Choice c. does not account for the hypernatremia.

http://www.emedicine.com/med/topic543.htm

Answer 3

seriously do your own homework.