What's this test for?

This test is ideal if you're experiencing unexplained muscle weakness, difficulty climbing stairs, frequent falls, or progressive muscle pain that hasn't been diagnosed. It helps identify specific antibodies linked to inclusion body myositis (IBM), a rare autoimmune condition that causes muscles to weaken over time, particularly in the thighs, forearms, and fingers. Many people use this test when they have persistent muscle symptoms that standard tests haven't explained.

What happens after I get my results?

You'll receive detailed doctor notes in simple language explaining what your antibody levels mean and whether they suggest an autoimmune muscle condition. These notes include personalized recommendations such as whether you should see a neurologist or rheumatologist, what additional tests might be helpful, and lifestyle modifications to manage symptoms. You'll also get the standard lab report and can track your antibody levels over time using our trends feature, which is especially helpful for monitoring disease progression or treatment effectiveness.

What's included in this test?

This test measures Cytosolic 5'-Nucleotidase 1A (cN-1A) Antibody (IgG). This specialized antibody test helps diagnose inclusion body myositis, a progressive muscle disorder that causes weakness and wasting. The cN-1A antibody is found in 35-70% of people with IBM and is particularly useful because it rarely appears in other muscle diseases, making it a valuable diagnostic marker when muscle weakness is unexplained.

How should I prepare for this test?

No special preparation is typically required for this antibody test. You can take your regular medications and eat normally before your blood draw. However, it's always a good idea to stay well-hydrated before any blood test to make the blood draw easier. If you have specific concerns about medications that might affect autoimmune testing, discuss them with your healthcare provider.

When will I get my results?

Results for this specialized antibody test typically take 7-10 business days, as it requires specialized laboratory analysis. More complex autoimmune panels may take slightly longer than routine blood tests. You'll receive an email notification as soon as your results are ready to view in your secure online account.

Who should consider getting this test?

This test is most appropriate for adults over 50 experiencing progressive muscle weakness, particularly in the thighs, forearms, wrists, and fingers. It's especially valuable if you have difficulty with activities like gripping objects, climbing stairs, or getting up from a seated position, and other muscle tests haven't provided clear answers. Your doctor may recommend this test if they suspect inclusion body myositis based on your symptoms and physical examination.

What symptoms indicate I may need this test?

Common symptoms that might warrant this test include slowly progressive muscle weakness over months or years, difficulty swallowing, frequent tripping or falling, trouble gripping objects or turning doorknobs, and weakness when climbing stairs. You might also notice muscle wasting in your forearms and thighs, or weakness that affects both sides of your body but isn't always symmetrical. These symptoms developing gradually, especially after age 50, are key indicators.

What is inclusion body myositis and why does it matter?

Inclusion body myositis (IBM) is a rare inflammatory muscle disease that causes slowly progressive muscle weakness and wasting, most commonly affecting people over 50. Unlike other muscle diseases, IBM typically affects specific muscle groups like the thighs, forearms, and finger flexors, and it progresses gradually over years. Getting an accurate diagnosis matters because it helps you understand your prognosis, access appropriate supportive care, and rule out other treatable conditions.

What does a positive cN-1A antibody result mean?

A positive result means that antibodies against cytosolic 5'-nucleotidase 1A were detected in your blood, which strongly supports a diagnosis of inclusion body myositis when combined with your symptoms and clinical evaluation. However, positive results can occasionally occur in people with other autoimmune conditions like Sjogren's syndrome, lupus, or other muscle diseases, so your doctor will interpret this result alongside your complete medical picture. A positive test helps confirm the diagnosis and guide your treatment plan.

What happens if my results are abnormal?

If your cN-1A antibody test is positive or equivocal, your doctor will likely refer you to a neurologist or rheumatologist who specializes in muscle disorders for further evaluation. Additional tests might include muscle biopsy, electromyography (EMG), or MRI to confirm the diagnosis and assess disease severity. While there's no cure for IBM, early diagnosis helps you access physical therapy, occupational therapy, and supportive treatments that can maintain your independence and quality of life longer.

Getting your blood test with us is easy, private & backed by the power of science.Long story short: In the test options, use the filters or search box to narrow your choices and find the test you want. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy! If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

How do I know which test to get?

In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option. Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.

When will my lab results be available?

Most test results will be available within 1–3 business days. Once they're ready, we'll send an email and text message to let you know. After your blood draw, just hang tight and don't worry – we'll keep you updated and in the loop! If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com, and we'll gladly help you.

Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?

Absolutely! We totally understand that errors can happen. No worries, we're here to help you. Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you. There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out. Our lab requires an address to be listed to generate an order.

Do you accept health insurance?

Only HSA & FSA is accepted. Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts. This policy applies to all insurance companies, including federal health insurance programs like Medicare. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

Can I cancel my order?

Yes. We get it – sometimes your needs change. As long as your samples haven’t been collected yet, we’re happy to help you cancel your order. If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com. You can read more about our cancellation policy here.

How can I find a lab location near me?

During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp). Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.

Muscle Weakness Test - Autoimmune Antibody Check

Getting your blood test with us is easy, private & backed by the power of science.

Long story short:

In the test options, use the filters or search box to narrow your choices and find the test you want.
If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!

754-799-7833

[email protected]

Blood Test for Muscle Weakness and Pain

Cytosolic 5'-Nucleotidase 1A (cN-1A) Antibody (IgG)

90 day happiness guarantee

Prescription & fees included

Easy to understand results

Fast & convenient

90 day happiness guarantee

Prescription & fees included

Easy to understand results

Fast & convenient

What's this test for?

How should I prepare for this test?

What's included in this test?

Here’s why 1,000,000+ customers chose us for affordable hassle-free private blood testing.

Blood Test for Muscle Weakness and Pain

90 day happiness guarantee

Prescription & fees included

Easy to understand results

Fast & convenient

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