NBME Review

Question 1

acute hemolytic transfusion reaction

Answer 1

*occurs because of ABO incompatibility
*mechanism: preformed antibodies against donor antigens on the surface of incompatible erythrocytes cause profound hemolysis
*clinical presentation: flank pain, fever, hemoglobinuria
*test: positive direct antiglobulin (Coombs) test
*treatment: immediate cessation of transfusion & supportive care

Question 2

transfusion-related acute lung injury (TRALI)

Answer 2

*clinical presentation: respiratory distress, often with associated hypoxemia, cyanosis, fever, and new infiltrates on CXR
*develops within 6 hours of transfusion of ANY blood product
*mechanism: abnormal priming of neutrophils in the lung undergo widespread activation and release cytokines upon exposure to inflammatory cytokines in blood product

Question 3

splenic laceration/rupture

Answer 3

*common after blunt abdominal trauma
*can lead to hemorrhage in peritoneal and retroperitoneal spaces
*leads to hemodynamic instability, characterized by tachycardia, hypotension, LUQ tenderness, peritonitis, referred pain to L shoulder
*tx: unstable pt = ex lap

Question 4

neurogenic shock

Answer 4

*may occur following traumatic brain or spinal cord injury due to disruption of autonomic fibers originating in the vasomotor center of the medulla oblongata
*loss of sympathetic innervation results in vasodilation and loss of vascular tone

Question 5

idiopathic intracranial hypertension (IIH)

Answer 5

*caused by inadequate resorption of CSF
*characterized by signs of increased ICP - headache, papilledema, increased opening pressure on LP without gross abnormality on imaging
*most common in young women with increased BMI

Question 6

basal cell carcinoma (BCC)

Answer 6

*most common form of skin cancer
*derived from basal cells of epidermis
*risk factors: UV light exposure > age, fair skin, FHx
*presentation: pink, pearly papules or nodules with rolled borders and central ulceration, commonly on sun-exposed areas of head and neck
*treatment: complete surgical excision with a margin of ~1 cm

Question 7

management of DVT / PE

Answer 7

*first-line = anticoagulation with heparin, LMWH, or DOACs
*thrombolytics are only used in severe cases

Question 8

cor pulmonale

Answer 8

*right ventricular dysfunction
*results from chronic pulmonary pathology (OSA, COPD, etc) and associated pulmonary hypertension
*mechanism: pulmonary HTN requires the R ventricle to pump against increased pressures, causing R ventricular dysfunction and remodeling
*presentation: exertional dyspnea & hypoxemia

Question 9

traumatic diaphragmatic hernia

Answer 9

*can occur after penetrating injury / blunt trauma
*caused by a sudden increase in intraabdominal pressure that leads to rupture of the diaphragm, leading to the presence of abdominal contents within the thorax
*clinical presentation: chest pain, SOB, bowel sounds in the lung fields
*tx: surgical exploration and repair of ruptured diaphragm

Question 10

Crohn disease

Answer 10

*characterized by transmural inflammation of GI tract, commonly involving the terminal ileum
*can arise anywhere in the GI tract
*clinical presentation: chronic abdominal cramping, bloody diarrhea, weight loss

Question 11

ulcerative colitis

Answer 11

*affects ONLY the COLON
*clinical presentation: abdominal pain, hematochezia, diarrhea, weight loss
*requires screening colonoscopy 8 years form date of diagnosis

Question 12

toxic megacolon

Answer 12

*a life-threatening medical emergency caused by extensive inflammation of the colon
*risk factors: ulcerative colitis / Crohn disease, infections (C. diff, etc), ischemic injury
*clinical presentation: high fever, tachycardia, hypotension, leukocytosis, enlarged and dilated bowel, impaired colonic motility

Question 13

ischemic colitis

Answer 13

*insufficient blood flow to an area of the intestine
*characterized by crampy abdominal pain, tenderness over affected bowel, hematochezia
*causes: occlusion of mesenteric vasculature (thromboembolism, dissection), hypotension, limited blood flow, aortic surgery

Question 14

cholangitis

Answer 14

*a bacterial infection or inflammation of the biliary tree
*Charcot triad: fever, RUQ pain, jaundice
*Reynold pentad: Charcot PLUS shock and altered mental status

Question 15

congenital biliary atresia

Answer 15

*the CBD is occluded, diminutive, or absent, so bile is unable to pass into the duodenum, precluding the use of bile to digest fats
*clinical presentation: progressive jaundice, pale stools, dark urine, poor weight gain

Question 16

urethral injuries

Answer 16

*characterized by difficulty voiding, blood at urethral meatus, perineal ecchymosis
*anterior urethra - commonly d/t straddle injuries
*posterior urethra - commonly d/t pelvic fractures
*evaluated by retrograde urethrography (injection of contrast into urethra to evaluate for extravasation)

Question 17

intraductal papilloma

Answer 17

*most common cause of unilateral bloody nipple discharge
*benign lesion of the ductal lining

Question 18

toxic adenoma

Answer 18

*adenoma autonomously produces T3 and T4, unregulated by normal negative feedback
*increased T4, low TSH, palpable single thyroid nodule
*sx of thyrotoxicosis: irritability, weight loss, diarrhea, heat intolerance, palpitations
*dx: thyroid ultrasound and radioactive iodine uptake scan