What does it mean to test negative for both AChR and MuSK antibodies?
When both AChR (acetylcholine receptor) and MuSK (muscle-specific kinase) antibody tests come back negative, this is called seronegative or double-negative myasthenia gravis. It's the rarest form of MG, affecting about 1 in 10 people with the condition.
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What does it mean to test negative for both AChR and MuSK antibodies?
When both AChR (acetylcholine receptor) and MuSK (muscle-specific kinase) antibody tests come back negative, this is called seronegative or double-negative myasthenia gravis. It's the rarest form of MG, affecting about 1 in 10 people with the condition.
Here's what makes seronegative MG different:
- It tends to affect younger people, including young adults and children
- Symptoms are often milder and mainly ocular (affecting the eyes)
- You may experience double vision, droopy eyelids, and trouble speaking or swallowing rather than generalized weakness
- It appears to affect females more often than males
Even without these antibodies, you can still have MG if your symptoms match and other tests support the diagnosis. A MGteam member shared: "None of my bloodwork was positive, but I was diagnosed on the basis of symptoms, nerve conduction studies, and response to pyridostigmine (Mestinon)."
Your neurologist might test for other less common antibodies like LRP4 if your main antibody tests are negative. The important thing is that negative antibody tests don't rule out MG - they just mean you have a different form of it.
November 5, 2025
I was dx'd double negative. No anti bodies
November 6, 2025
I am also seronegative but my doctor has not given me a diagnosis. More tests.
Georgia Erickson
November 5, 2025
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