Synonyms

ACR, AChR Ab

Clinical Indications

ACR antibodies are indicated in investigation of suspected Myasthenia Gravis (MG) in which muscles tire or become fatigued very easily. Muscles around the eyes are commonly affected first (2 in 3 cases), causing drooping eyelids and double vision. Muscles around neck, face and throat are commonly affected causing difficulty in swallowing, speaking and chewing. Weakness in the arms, legs and other skeletal muscles may develop.

Request Form 

Combined Pathology Blood form (Yellow/Black or Blue for GP's)

Availability

Analysed by referral laboratory if specific criteria met.

Specific Criteria

Patient with suspected myasthenia gravis

Turnaround Time

2 to 3 weeks

Specimen

Serum

Volume

1 ml

Container

Yellow top (SST) tube

Lab. Handling

Aliquot and store at 4C 

Causes for Rejection

Unlabelled sample. 

Reference Range

Negative

Interpretation

ACR antibodies are seen in over 80% of patients with MG, and are probably responsible for most of the symptoms; they are not seen in the rare congenital form of the disease. They may occur in ocular myasthenia, and penicillamine-induced myasthenia, but are not seen in healthy individuals.  
Antibody positive patients should also be checked for skeletal (striated) muscle antibodies: when both are positive, this is a consistent with myasthenia associated with thymoma.