HMGCR Autoantibodies

Also known as: HMG; Statin associated myopathy; necrotising myopathy

The clinical management of inflammatory myopathies can be guided according to the demonstation of Myositis specific autoantibodies (MSA).

Recently, auto-antibodies (AAbs) to the enzyme, 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) was shown to be a MSA that was strongly associated with immune mediated necrotising myopathy (Arthritis Rheum. 2010 Sep;62(9):2757-66. doi: 10.1002/art.27572). HMGCR AAb positive patients present with progressive, irritable myopathy of the proximal muscles, with oedema on MRI and a Creatinine Kinase typically 10x the upper limit of normal.

The cohort of HMGCR positive patients has been shown to be varied, therefore age and statin exposure should not exclude the differential of HMGCR positive necrotising myositis (Liang doi:10.1093/rheumatology/kew386).

There is a strong association of necrotising myositis with co-existent malignancy, which increases with age: patients with histologically proven necrotising myositis who are AAb negative or HMGCR AAb positive have an increased incidence of co-existent malignancy (21.4 and 11.5 percent respectively) (Allenbach doi:10.1093/brain/aww054).

Specimen requirements

0.5ml of separated serum

Cost

£15

Laboratory turnaround time

14 working days

Laboratory method

Chemiluminescence

Reference range/units

Negative = <14.9 CU/ml
Equivocal = 15-24.9 CU/ml
Positive = >25.0 CU/ml

Associated tests

Myositis Western blot

Sample stability

2 months at 2-8ºC

Shipping and storage

UK and Ireland

Ambient temperature and first class post. Hays DX users please enquire via email below.

International

Ambient temperature if courier will deliver within 72 hours otherwise consider refrigerated transport. Freezing is not a requirement.

Ensure delivery Monday to Friday 09:00 - 17:30.

Further information and contact details

For further information, email andrew.woods2@nhs.net