USMLE Step 1

A 33-year-old man presents to his physician to discuss his plans for treatment of hyperthyroidism. One of the options is potassium perchlorate. What is the mechanism of action of potassium perchlorate as anti-thyroid? A-Blocking of coupling of iodotyrosines B-Blocking of peroxidase catalyzed reactions C-Blocking of peripheral deiodination of T3 and T4 D-Competitive inhibition of iodide … Read more

An 18 year-old student visits her physician for a routine physical examination. She has no complaints. Physical examination is unremarkable except for a mid-systolic click followed by a late systolic murmur heard at the lower left sternal border and apex. The murmur duration increases in standing and shortens with squatting. Electrocardiogram (ECG) shows no abnormalities. … Read more

A 36-year-old man comes to the office for evaluation of involuntary movements of his hands and feet. These movements developed gradually over the past 3 years. He is otherwise in a good health and takes no medication. He does not smoke or drink alcohol. He does not drink any caffeinated beverages or use any recreational … Read more

A 6-year-old boy presents with fever, malaise, cough, running nose and conjunctivitis. His past medical history indicates that he did not receive any immunizations due to his parents’ religious belief. On examination, his temperature is 102.7 F and there are white spots on a red base close to his second molar teeth. He also has … Read more

A 69 year-old man with a long history of poorly controlled diabetes presents to his physician complaining of pain and drainage in his left ear. His vital signs are within normal limits. The pinna of his left ear is tender. The external meatus is swollen and covered with purulent drainage. What is the most likely … Read more

Three boys are brought to the urgent care clinic complaining of fever, sore throat and itchy eyes. On examination, their temperature range from 101.2 F to 102.7 F. Their conjunctivas are red and inflamed. They are a part of a group of five kids from alimentary school camp out on the lake. Which of these … Read more