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Correct Answer: A Section: (none)

Explanation:

The patient is hypercalcemic and has laboratory features suggesting dehydration, as do most patients with symptomatic hypercalcemia. Initial management would include saline rehydration, which replaces volume deficits, dilutes the elevated serum calcium, and promotes urinary calcium excretion. The addition of loop diuretics such as furosemide can also increase calciuresis, but should only be added after the patient has had adequate volume repletion. Administration of bisphosphanates, such as pamidronate or zoledronate, provide more powerful reduction of serum calcium by inhibiting bone resorption and liberation of calcium. Their effects may last for several weeks, but their onset of action does not occur for 12 days. Subcutaneous calcitonin can provide a faster onset of action to inhibit bone resorption within a few hours, but patients develop tachyphylaxis and become unresponsive to the drug effect within 2448 hours.

Most cancer patients with hypercalcemia develop this problem as a paraneoplastic phenomenon, due to the production of a parathyroid hormone-related protein (PTHrP).

This problem, called humoral hypercalcemia of malignancy (HHM), is very common, affecting 510% of all cancer patients. The diagnosis is usually straightforward, as there is a readilyavailable laboratory assay for PTHrP. Other cancer patients develop HHM due to the production of an enzyme that converts 25hydroxyvitamin D to the more active 1,25-hydroxyvitamin D, similar to the hypercalcemia seen in patients with granulomatous diseases. Severe hypercalcemia solely due to the presence of osteolytic metastases is much less common. Hyperparathyroidism and medications such as thiazide diuretics can also cause elevations of serum calcium, but usually not to the severe levels seen in HHM.

Correct Answer: A Section: (none)

Explanation: Wound infection is a complication of surgery that can lead to a great deal of morbidity and longer hospital stay. Prevention of wound infection includes perioperative antibiotics, which should be at their peak tissue concentration at the time of skin incision. This means they should be given at least 30 minutes prior to incision. Patients who have other infections, such as urinary tract infections, are at increased risk for wound infection. Bowel surgery exposes the wound to the normal intestinal flora, the most common being Bacteroides. Washing hands is an essential part of preventing spread of infectious pathogens between patients. Using gloves is not a substitute for good hand hygiene. Once a wound is infected, it must be opened and drained. Antibiotic therapy alone is not adequate.

Correct Answer: C Section: (none)

Explanation:

Pelvic ultrasound is the least invasive and most cost-effective test to diagnose uterine fibroids. MRI is useful but not always readily available and much more expensive. Plain radiographs would not be helpful, and office laparoscopy is impractical and potentially dangerous given the presumed size of her uterus. A hysterosalpingogram would only note filling defects within the uterine cavity and miss intramural or subserosal fibroids.

GnRH agonists have been used widely for preoperative treatment of uterine fibroids. They work by inducing amenorrhea, which improves hematologic parameters and decreases uterine volume. Although nonsteroidal anti-inflammatory drugs (NSAIDs) may help decrease bleeding for some patients with fibroids, they have not been reliably shown to decrease fibroid size. The other agents (OCPs, progesterone, and narcotics) do not have these effects and generally are not effective in treating dysfunctional uterine bleeding caused by anatomic lesions such as fibroids

Correct Answer: C Section: (none)

Explanation:

Hashimoto thyroiditis is a very common cause of hypothyroidism in the parts of the world where iodine levels are insufficient. The clinical picture is characterized by a gradual enlargement of the thyroid gland with autoimmune destruction. There is a great female to male predominance, with ratio of 10

20:1. Clusters of families are seen which are associated with HLA-DR5 on the major histocompatibility complex (MHC). A few cases are also characterized by HLA-DR3. The pathogenesis is attributed to cellular and humoral immunity which produces thyroid tissue injury. The morphology of the thyroid gland is characterized by typical destruction of the thyroid parenchyma with dense lymphocytic infiltrate and many secondary germinal centers. Occasional scattered Hurthle cells are also seen. Depending on the stage of the disease, extensive areas of fibrosis may also be present. The clinical course of Hashimoto thyroiditis is usually an initial period of time in which the patient may be euthyroid followed by hypothyroidism.

Correct Answer: A Section: (none)

Explanation:

Ranson's criteria represent a series of chemical clinical measurements that can be used to estimate the prognosis of an acute episode of pancreatitis. These markers are not meant for diagnosis of pancreatitis, but rather can be used to help gauge the severity of the disease and subsequently triage patients to the appropriate level of care. The criteria are measures of events that occur at admission and over the first 48 hours of hospitalization (see table below). Patients who meet three to four of the criteria have an estimated mortality of 15% and approximately 50% will require admission to the ICU. Essentially, all patients with five or more criteria will need to be cared for in the ICU, while patients with seven to eight positive criteria have a >90% mortality. It is important to note that amylase, lipase, and platelet counts are not considered in these criteria.