MDS PREP
What is the primary target of warfarin in the prevention of thrombosis?
1) Platelets
2) Vitamin K-dependent clotting factors
3) Fibrin
4) Factor VIII
Warfarin acts by inhibiting the vitamin K-dependent synthesis of factors II, VII, IX, and X, as well as proteins C and S. This anticoagulant effect decreases the formation of thrombin and fibrin and is used to prevent thrombus formation and embolization in conditions such as atrial fibrillation and heart failure.
What is the most common cause of death in patients with pulmonary embolism?
1) Right ventricular failure
2) Respiratory failure
3) Recurrent embolism
4) Hemorrhagic stroke
The most common cause of death in patients with pulmonary embolism is right ventricular failure. This occurs when the right ventricle of the heart is unable to pump blood effectively due to the sudden increase in pulmonary vascular resistance from the embolism.
In humoral hypercalcemia of malignancy (HHM), what is the most common overproduced substance leading to hypercalcemia?
(1) Parathyroid hormone (PTH)
(2) Parathyroid hormone-related protein (PTHrP)
(3) 1,25-dihydroxyvitamin D (1,25(OH)2D)
(4) Calcitonin
PTHrP is a protein that is structurally similar to parathyroid hormone (PTH) but is produced by some tumor cells. It acts on the PTH receptor, leading to increased calcium levels in the blood, similar to PTH. HHM is most often associated with overproduction of PTHrP by tumors, causing hypercalcemia without the typical elevation in PTH levels seen in primary hyperparathyroidism.
A patient is admitted with suspected cholera. What is the most appropriate initial treatment for this condition?
(1) Intravenous antibiotics
(2) Intravenous fluids and electrolytes
(3) Intravenous opioids
(4) Intravenous corticosteroids
The most critical aspect of cholera treatment is aggressive rehydration to replace the large volume of fluid and electrolytes lost through diarrhea. Antibiotics may be administered to reduce the duration of illness and the volume of diarrhea, but rehydration is the immediate priority.
What is the characteristic gait abnormality seen in patients with advanced Huntington's disease?
1) Festinating gait
2) Spastic gait
3) Ataxic gait
4) Choreic gait
The characteristic gait abnormality in Huntington's disease is the choreic gait, which is disjointed and poorly coordinated with a "dancing" quality.
What is the role of tissue plasminogen activator (tPA) in the treatment of pulmonary embolism?
1) Prevents thrombus formation
2) Dissolves existing thrombi
3) Inhibits platelet aggregation
4) Enhances fibrinolysis
tPA is a thrombolytic agent used to dissolve blood clots. In the treatment of pulmonary embolism, it is administered to break down the clot in the pulmonary artery, thereby improving blood flow and reducing the risk of complications.
Which of the following is NOT a common symptom of valvular heart disease?
1) Shortness of breath
2) Rapid heartbeat
3) Chest discomfort
4) Abnormal body temperature
Valvular heart disease symptoms typically include weakness on exertion, rapid heartbeat, chest discomfort, and fainting spells. However, an abnormal body temperature is not a common symptom associated with valvular heart disease.
A patient with diabetes mellitus and chronic kidney disease is prescribed chloramphenicol for a bacterial infection. What is a potential adverse effect of this medication that requires careful monitoring in this patient population?
(1) Nephrotoxicity
(2) Hepatotoxicity
(3) Ototoxicity
(4) Neutropenia
Chloramphenicol is known to have nephrotoxic effects and can exacerbate pre-existing kidney damage. It is essential to monitor renal function closely in patients with diabetes and chronic kidney disease when administering this antibiotic.