acetylcholine (nicotinic) receptor blocking Ab in serum

Indications

• evaluation of myasthenia gravis (MG)

Reference interval

• < 20% inhibition of I=125-alpha-bungarotoxin

Principle

• 3rd line diagnostic test for myasthenia gravis (MG)
• measures inhibition of I-125-alpha-bungarotoxin to nicotinic receptor substrate

Clinical significance

• positivity:
  • 61% in generalized MG
  • 25% in ocular MG
  • 35% of MG in remission

Methods

• Radioimmunoassay (RIA)

Specimen

• serum
• store refrigerated or frozen without preservative
• do NOT use plasma
• stable at -20 degrees C Clinical Guide to Laboratory Tests, 3rd ed. Teitz ed., W.B. Saunders, 1995

More general terms

• acetylcholine (nicotinic) receptor modulating Ab in serum

Additional terms

• myasthenia gravis
• nicotinic receptor (nicotinic acetylcholine receptor, nAChR)