Main Disease Association
Mixed connective tissue disease (MCTD)

Category
Antibody

When to Order
* If +ANA and concern for rheumatic disease (lupus, mixed connective tissue disease)
* Look for the following signs or symptoms: Raynaud’s, rashes, cytopenias, inflammatory arthritis, myositis

What It Means If Positive
* HIGHLY SPECIFIC for MCTD when present in high titer.
* NECESSARY for diagnosis of MCTD, but not sufficient for diagnosis – lab test alone doesn’t make diagnosis and need clinical signs and symptoms of MCTD as well
* Patients with this antibody are less likely to develop severe renal or neurologic disease.

What It Means If Negative
* Highly sensitive for MCTD, so if negative, patient does not have MCTD.