A diagnostic test for suspected myasthenia gravis uses edrophonium chloride (Tensilon). What is the expected outcome after administration?

Prepare for the Virginia HESI Level 4 Test with an array of study materials including flashcards and multiple choice questions. Each question comes with hints and detailed explanations to assist in your exam preparation. Get set to ace your test!

Multiple Choice

A diagnostic test for suspected myasthenia gravis uses edrophonium chloride (Tensilon). What is the expected outcome after administration?

Explanation:
Edrophonium chloride briefly inhibits acetylcholinesterase, raising acetylcholine levels at the neuromuscular junction. In myasthenia gravis, where antibody damage reduces functional receptor activity, this extra acetylcholine temporarily improves transmission across the NMJ. The result is a quick, transient improvement in muscle strength, especially in fatigable muscles like the eyelids and proximal muscles. So the expected outcome is a decrease in muscle weakness after the dose. (No change or worsening would argue against MG, and seizures are not a typical effect of this test.)

Edrophonium chloride briefly inhibits acetylcholinesterase, raising acetylcholine levels at the neuromuscular junction. In myasthenia gravis, where antibody damage reduces functional receptor activity, this extra acetylcholine temporarily improves transmission across the NMJ. The result is a quick, transient improvement in muscle strength, especially in fatigable muscles like the eyelids and proximal muscles. So the expected outcome is a decrease in muscle weakness after the dose. (No change or worsening would argue against MG, and seizures are not a typical effect of this test.)

Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy