ABEM ABEM Pharmacology & Medical Management 1 — Questions and Answers
Question 1: Which medication class can cause a length-dependent peripheral neuropathy as a side effect?
- Beta-blockers
- Statins
- Platinum-based chemotherapy agents (Correct answer)
- ACE inhibitors
Correct answer: Platinum-based chemotherapy agents
Cisplatin and other platinum-based chemotherapeutics cause a sensory-predominant length-dependent neuropathy by accumulating in dorsal root ganglia neurons.
Question 2: Pyridostigmine is used in myasthenia gravis because it:
- Blocks nicotinic acetylcholine receptors
- Inhibits acetylcholinesterase, increasing synaptic ACh (Correct answer)
- Promotes antibody clearance from the NMJ
- Stimulates presynaptic ACh release
Correct answer: Inhibits acetylcholinesterase, increasing synaptic ACh
Pyridostigmine inhibits acetylcholinesterase, preventing breakdown of acetylcholine and prolonging its availability at the neuromuscular junction.
Question 3: A patient with Lambert-Eaton Myasthenic Syndrome (LEMS) would most likely benefit from which pharmacological agent?
- Pyridostigmine
- 3,4-Diaminopyridine (amifampridine) (Correct answer)
- Plasma exchange only
- Botulinum toxin
Correct answer: 3,4-Diaminopyridine (amifampridine)
3,4-Diaminopyridine blocks presynaptic potassium channels, prolonging the action potential and increasing calcium influx to enhance ACh vesicle release.
Question 4: Which vitamin deficiency is classically associated with a peripheral neuropathy affecting both sensory and motor fibers?
- Vitamin A
- Vitamin B12 (cobalamin) (Correct answer)
- Vitamin D
- Vitamin K
Correct answer: Vitamin B12 (cobalamin)
Vitamin B12 deficiency causes subacute combined degeneration affecting the dorsal columns and peripheral nerves, producing a sensorimotor neuropathy.
Question 5: Corticosteroids are used in inflammatory myopathies such as polymyositis primarily because they:
- Directly repair damaged muscle fibers
- Suppress the aberrant immune-mediated attack on muscle (Correct answer)
- Increase acetylcholine at the NMJ
- Stimulate satellite cell proliferation
Correct answer: Suppress the aberrant immune-mediated attack on muscle
Corticosteroids suppress the autoimmune inflammatory cascade that causes muscle fiber destruction in inflammatory myopathies.
Question 6: Which drug used in the treatment of ALS has been shown to modestly slow disease progression?
- Prednisone
- Riluzole (Correct answer)
- Baclofen
- Gabapentin
Correct answer: Riluzole
Riluzole, a glutamate release inhibitor, is FDA-approved for ALS and modestly extends survival by reducing excitotoxic motor neuron injury.
ABEM ABEM Pharmacology & Medical Management 1
Which medication class can cause a length-dependent peripheral neuropathy as a side effect?