Smooth Muscle Antibody (Actin)
A key autoantibody for distinguishing autoimmune hepatitis from other causes of abnormal liver tests.
Consider this test if:
- Persistently elevated liver enzymes with no clear cause
- Working up suspected autoimmune hepatitis alongside ANA and IgG
- Investigating fatigue, jaundice, or right upper quadrant discomfort with abnormal liver tests
- Distinguishing autoimmune liver disease from viral, alcoholic, or fatty liver causes
- HSA/FSA eligible
- Typical results in 2-3 days · Reviewed by a real clinician
- Drawn at a CLIA/CAP-accredited lab near you ·
Pre-test considerations
No fasting required and no special timing needed. A standard blood draw is all that is involved.
Video consult with your Care Team
A 1:1 call to discuss your health.
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What this test is for
Smooth muscle (actin) antibodies are autoantibodies directed against actin, a structural protein in smooth muscle cells, and they are a hallmark serologic marker of autoimmune hepatitis. They appear in roughly 52% to 85% of people with autoimmune hepatitis or chronic active hepatitis, and in about 22% of people with primary biliary cholangitis (formerly primary biliary cirrhosis). The test is typically ordered when liver enzymes are persistently elevated and the cause is unclear, especially alongside unexplained fatigue, jaundice, joint aches, or abnormal imaging. A positive result supports an autoimmune cause and is interpreted with other markers such as ANA, total IgG, and often a liver biopsy. A negative result does not fully exclude autoimmune hepatitis, since a minority of cases are seronegative.
- Specimen
- Serum
- Measures
- Concentration
What you'll learn
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Insights that connect the dots. A clinician reads your whole picture, not one result in isolation, connecting family history, past results, and lifestyle into clear next steps.
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Your personalized action plan. Nutrition, supplements, and training in one clinician-reviewed protocol, updated as your results change.
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Track your trends. Upload results from any lab and see each biomarker trend over time, so you know what is working.
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Never miss a recheck. Mito tells you what is worth retesting and when, then reminds you so nothing slips.
What to expect
- 1 Book instantly
Click, book, done. Choose a convenient lab location near you. Transparent, up-front pricing.
- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Typical results in 2-3 days
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
Included with Mito membership. A clinician reviews your results and your personalized action plan follows, with clear next steps.
Everything your health needs,
in one membership
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Every test at our cost
Members pay our cost on every test, with lab fees passed straight through. The full receipt is itemized, never padded.
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Continuous tracking, all in one place
Upload past labs and watch your trends over time. Every marker and visit lives in one longitudinal record, so all your care stays together.
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Year-round clinician support
Text anytime and get clinician-reviewed answers. When you want to go deeper, 1:1 consultations are available at affordable rates.
All for $9/month
Order any test or consult without joining. For $9/month, members unlock member prices, trend tracking, and year-round clinician guidance.
Mito Membership
$9 /mo
cancel anytime
Without membership
$0
pay as you go
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Frequently asked questions
View all FAQsHow does pricing work?
Every test shows the member price next to the standard non-member price, so you can see what membership saves you. The member price is our cost, covering the lab and what it takes to run the service. It is never a profit on the test itself. Mito makes its money on the $9 membership, not on marking up your tests. Membership is $9 per month, and any applicable lab order or draw fee is itemized before you pay.
Where do I get tested?
Choose an available partner lab at checkout. If your cart contains multiple blood tests, Mito helps consolidate the eligible tests at one lab when possible. At-home kits and scans follow the collection or appointment process shown on their product page.
Is this eligible for HSA/FSA?
Yes. Eligible tests can be paid for with an HSA or FSA card at checkout.
When will I get my results?
Your results appear in your Mito dashboard after the laboratory completes processing. A clinician then reviews them before your analysis and personalized action plan are finalized. Timing varies by test, and specialty assays and at-home kits may take longer.
Do I need a physician's order?
No. Mito provides the laboratory order when one is required, so you do not need to arrange a separate physician visit before purchasing.
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