Muscle Specific Tyrosine Kinase (MUSK)

Department of Immunology

Notes

• Muscle specific tyrosine kinase (MuSK) is a surface membrane enzyme that is essential in aggregating Acetylcholine receptor during the development of the neuromuscular junction.
• About 3-7% of patients with myasthenia gravis have antibodies against MuSK, with the majority (80-90%) of patient being positive to antibodies against the acetylcholine receptor. In around 10% of patients antibodies are not detected.
• Anti-Musk antibodies have not been found in patients with purely ocular myasthenia or in those with anti-acetylcholine receptor antibodies.
• Test performed at Immunology Dept., Churchill Hospital, Oxford.

Sample Requirements

(No patient preparation or special handling required)

Adult

5ml Gold-top SST tube or 3.5ml Rust-top gel tube (Trust users only)

Paediatric

1ml Serum Sample

Turnaround Times

4 weeks

Time Limit for Add-ons

3 days

Reference Range

Negative = Normal