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Correct Answer: E Section: (none)

Explanation:

Oral corticosteroids are a mainstay of firstline treatment for moderate-to-severe ulcerative colitis. Starting doses of 40 mg PO daily of prednisone, with a slow taper, are often effective in reducing colonic inflammation, although some patients are unable to wean steroids or maintain remission once achieved. The patient does not have dysplasia in any biopsy specimens, nor does he have signs of systemic toxicity, so a colectomy would be premature. Oral metronidazole is ineffective in ulcerative colitis. Cortisone enemas would be helpful if the patient had isolated left-sided disease, but it is doubtful that enema therapy would reach his hepatic flexure. Intravenous cyclosporine would be used in severe colitis as a last measure before colectomy but this patient is not yet sick enough to warrant such therapy. PSC occurs in approximately 3% of patients with ulcerative colitis and is its major liver complication. It is a chronic inflammatory condition of the biliary tree. It can typically manifest with elevated alkaline phosphatase and bilirubin levels, and results in diffuse stricturing and pruning of the biliary tree. Wilson disease, hereditary hemochromatosis and alpha-1 antitrypsin deficiency are not associated with ulcerative colitis and are not cholestatic liver diseases. Primary biliary cirrhosis could account for these laboratory findings, but is rare in both males and patients with ulcerative colitis. Patients with PSC are at increased risk of developing cholangiocarcinoma but not the other liver tumors mentioned. Patients with celiac sprue are at increased risk for small bowel cancers (adenocarcinoma, lymphoma). Patients with FAP are at increased risk to develop desmoid tumors.

Correct Answer: A Section: (none)

Explanation:

Atrial fibrillation is the most common sustained clinical arrhythmia. It occurs in approximately 4% of the population over the age of 60. It is diagnosed by the presence of irregularly irregular QRS complexes on an ECG with an absence of P waves. The QRS complex is most commonly narrow, as this is a supraventricular arrhythmia. Wide QRS complexes can occur if there is an underlying conduction abnormality, such as Wolff-Parkinson-White syndrome or a bundle branch block. Saw-tooth Pwaves occur in atrial flutter, another atrial arrhythmia that may present similarly to atrial fibrillation but which is less common. The saw-tooth P waves, or flutter waves, are representative of an atrial rate typically in the range of 300350/minute.

Not infrequently, atrial flutter will lead to atrial fibrillation. Q waves in II, III, and aVF would be seen if there had been a previous inferior MI. Peaked T waves are seen in certain conditions, such as hyperkalemia, but are not routinely associated with atrial fibrillation. Atrial fibrillation may be precipitated by both cardiac and noncardiac conditions. Among the noncardiac conditions are metabolic abnormalities, which include hyperthyroidism. Of the tests listed, a suppressed TSH level, consistent with hyperthyroidism, would be most likely to be causative of atrial fibrillation. Troponin may be elevated in acute myocardial ischemia. Atrial fibrillation can occur following a MI, particularly when complicated by CHF. This is not consistent with the clinical scenario presented. Renal disease and diabetes may contribute to some of the conditions that can predispose to the development of atrial fibrillation, such as metabolic derangements or CAD. Acute and chronic pulmonary disease may also precipitate atrial fibrillation. In the setting of a man who is otherwise healthy and without significant medical history, new-onset atrial fibrillation would be less likely to be the initial presentation of diabetes, renal failure, or pulmonary disease than hyperthyroidism. For this reason, choice A is the single best answer of those provided.

Correct Answer: D Section: (none)

Explanation:

Any new palpable breast lesion in females (or males) of any age necessitates a mammographic evaluation and biopsy. Delay is inadvisable. Serum tumor markers, such as CA-27/29 (or even less specifically CEA), are useful to follow tumor response to therapy; however tumor markers are not reliable as diagnostic tools in breast cancer because of a relatively low sensitivity. Lobular carcinomas are frequently not visualized on mammogram, particularly standard mammograms; ultrasound however detects these tumors and should be ordered when a palpable lesion is not detected on a mammogram.

Correct Answer: D Section: (none)

Explanation:

Like other trauma patients, the initial management of burn patients is crucial in improving survival and function. Inhalation injury should be suspected in anyone with a history of confinement in smoke, facial burns, singed eyebrows or nasal hairs, carbonaceous sputum, or carboxyhemoglobin levels greater than 10%. These patients sometimes look stable initially but soon develop airway edema. These patients should be placed on high-flow oxygen and observed closely. There should be a very low threshold for endotracheal intubation to protect the airway. Burn patients require large volume fluid resuscitation that should begin immediately. If patients develop pulmonary edema, they should be intubated. Fluid resuscitation should not be withheld to prevent intubation. Heat loss is also a major concern in burn patients who have lost their thermoprotective skin covering. They should be wrapped in warm, moist dressings. Depth of burn affects management in resuscitation efforts, as well as need for debridement or escharotomy, and should be evaluated in every patient. The American Burn Association recommends transfer to a burn center for patients with: · Partial thickness and full thickness burns of >10% of total body surface area TBSA in patients with age <10 years old or >50 years old · Partial or full thickness burns of >20% in patients of any other age · Partial or full thickness burns involving face, hands, feet, genitalia, or perineum · Full thickness burns of >5% TBSA in any age group · Significant electrical or chemical burns · Inhalation injury

Correct Answer: E Section: (none)

Explanation:

Sinus histiocytosis represents hyperplasia of the endothelial lining of the sinusoids, which become dilated and contain many histiocytes. This reaction, which is also called reticular hyperplasia, becomes very prominent in lymph nodes when they are draining a cancerous process. This is particularly common in the axillary nodes when cancer of the breast has been detected. It is thought to represent an immune response to the host against the tumor products.