Clinical Case Conundrums
Pharmacology Frenzy
Anatomy Adventures
Micro-Marvels
Path-Puzzles
100
A patient presents with a painful vesicular rash in a dermatomal distribution. What virus is responsible for this condition?
Herpes zoster (shingles)
100
What type of receptors do the majority of antihistamine drugs bind to?
H1 Receptors
100
Which of the following types of muscle contraction in muscle energy is associated with no change in muscle length?
Isometric
100
What protozoa can cross the placenta and cats are the definite host?
Toxoplasma gondii
100
A 77-year-old man with hypertension, type 2 diabetes mellitus, and atrial fibrillation is admitted to the hospital because of a 3-hour history of nausea and flank pain. Two days after admission, he suddenly develops aphasia and left-sided paralysis. Despite appropriate life-saving measures, he dies. A photograph of a section of the spleen obtained at autopsy is shown. Microscopic examination of the pale region in the photograph shows preserved cellular architecture with eosinophilic cytoplasm and no visible nuclei. Which of the following pathological changes is most likely responsible for the splenic findings on autopsy?
Coagulative Necrosis
200
A 30-year-old male presents with abdominal pain, diarrhea, and weight loss. Colonoscopy shows skip lesions in the terminal ileum with rectal sparing. What is the most likely diagnosis?
Crohn's disease
200
Which clotting factors are inhibited by warfarin?
Warfarin inhibits clotting factors II, VII, IX, and X
200
The loss of which structure would eliminate peristalsis of the GI tract?
Myenteric plexus
200
What gram-negative bacilli is multi-drug resistant and produces pyocyanin?
Pseudomonas
200
An otherwise healthy 8-month-old girl is brought to the physician because of a lesion on her back. Her mother reports that the lesion has been present since shortly after birth and has been rapidly increasing in size. Vital signs are within normal limits. Examination of the upper back shows a 2.8-cm, flat, reddish-purple, sharply demarcated skin lesion that is nontender and blanches with pressure. A biopsy of the lesion is obtained; microscopic examination of the specimen shows dense cords of mitotically active endothelial cells and few small-caliber vessel lumina that contain red blood cells. Which of the following is the most likely outcome if the patient's lesion is left untreated?
Spontaneous Involution
300
A 40-year-old female complains of fatigue, weight gain, and cold intolerance. TSH is elevated, and free T4 is low. What is the likely diagnosis?
Hypothyroidism, (Hashimoto's thyroiditis)
300
This bronchodilator, commonly used in the treatment of asthma, works by stimulating beta-2 adrenergic receptors. What is it?
Albuterol
300
A 42-year-old woman presents to the clinic with bulging in her groin that worsens when she coughs. She is diagnosed with a femoral hernia and scheduled for hernia repair. During the repair, the clinician would expect which structure to be located just superior to the herniated bowel?
Inguinal ligament
300
Which class of antibiotics has tendon rupture and seizures as an adverse effect?
Fluoroquinolone
300
A previously healthy 46-year-old woman comes to the physician with a one-week history of productive cough and fatigue. Two weeks ago, she had fever, nasal congestion, rhinorrhea, and myalgias that resolved with supportive care. She has not traveled out of the United States. Pulmonary examination shows dullness to percussion and increased fremitus anteriorly over the right lung. An x-ray of the chest is shown. A sputum sample is most likely to show which of the following findings?
Gram+, catalase+ cocci (Staph aureus)
400
A 45-year-old male presents with crushing chest pain radiating down the left arm. ECG shows ST-segment elevation in leads II, III, and aVF. What is the most likely diagnosis?
an inferior myocardial infarction
400
This class of drugs, including enalapril and lisinopril, is commonly used in the treatment of hypertension. What is their mechanism of action?
ACE inhibitors. They block the conversion of angiotensin I to angiotensin II
400
A 45-year-old female is diagnosed with left-sided renal carcinoma that has invaded the renal artery, a direct branch from which artery?
Aorta
400
What DNA virus is partially double stranded and enveloped?
Hepadna
400
A 45-year-old woman gravida 1, para 1, comes to the physician because of a lump that she noticed in her right breast. She otherwise feels well and has not had any breast pain or nipple discharge. She had right breast mastitis 10 years ago while breastfeeding but has no other history of serious illness. Palpation of the right breast shows a 3-cm firm, nontender mass with well-defined margins lateral to the right nipple. There is a dimpling of the skin overlying the mass but no rash. The left breast is normal. Mammography shows a density with calcifications in a star-shaped formation in the same location as the mass. Microscopic examination of a biopsy specimen from the breast mass shows disorganized nests of glandular cells that express E-cadherin and are surrounded by fibrous tissue. Which of the following is the most likely diagnosis?
Invasive Ductal Carcinoma
500
A 38-year old female with a history of joint pain, positive syphilis test, 7 miscarriages, and the CBC shows thrombocytopenia. What is the most likely diagnosis?
Antiphospholipid Syndrome (APS)
500
This drug, often used in the treatment of opioid overdose, competes with opioids for receptor binding and can reverse respiratory depression. What is it?
Naloxone (opioid receptor antagonist)
500
A 67-year-old man comes to the office to discuss surgical repair of his previously diagnosed abdominal aortic aneurysm (AAA). What structures is most at risk for ischemia during the operation?
Sigmoid colon
500
What plate agar will produce yellow orange colonies when fermenting bacteria is plated?
Hektoen enteric agar
500
A 73-year-old man with coronary artery disease and hypertension is brought to the emergency department by ambulance 90 minutes after the acute onset of substernal chest pain and dyspnea. He has smoked 2 packs of cigarettes daily for 52 years. Shortly after arriving at the hospital, he loses consciousness and is pulseless. Despite attempts at cardiopulmonary resuscitation, he dies. Examination of the heart at autopsy shows complete occlusion of the left anterior descending artery with a red thrombus overlying a necrotic plaque. Which of the following pathophysiologic mechanisms is most likely responsible for this patient's coronary occlusion?
Secretion of Matrix Metalloproteinases