What's this test for?

This test is ideal if you're being treated for a cytomegalovirus (CMV) infection but aren't responding well to your current antiviral medication. It's often used for people with weakened immune systems, such as transplant recipients, who need ongoing CMV treatment. The test checks whether the virus has changed in a way that makes it resistant to specific antiviral drugs.

What happens after I get my results?

Your results will show up in your account along with an explanation of what the findings mean for antiviral drug resistance. If a resistance mutation is found, the report outlines which drugs the virus may no longer respond to, so treatment can be adjusted accordingly. You can download a standard lab report from your account at any time, and if you're retested later, you'll be able to track changes over time using the trends feature. Because this test relates to active infection management, any concerning results should prompt quick follow-up care.

Who should consider this test?

People currently being treated for CMV infection who aren't improving on their current antiviral medication are good candidates for this test. It's especially relevant for those with weakened immune systems, such as organ or stem cell transplant recipients, since they're more likely to develop drug-resistant CMV. If your viral load isn't dropping despite treatment, this test can help explain why.

What symptoms indicate I may need this test?

Signs that CMV treatment isn't working include a viral load that stays high or keeps rising despite being on antiviral medication, ongoing fever, fatigue, or organ-related symptoms that don't improve. People with weakened immune systems may also notice worsening symptoms like vision changes, digestive issues, or breathing problems. If these signs continue after weeks of antiviral treatment, resistance testing can help identify the cause.

What is CMV drug resistance and why does it matter?

CMV drug resistance happens when the virus changes its genetic code in a way that makes antiviral drugs like Ganciclovir or Foscarnet less effective. This matters because it means the medication you're taking may not be clearing the infection, allowing the virus to keep multiplying. Identifying resistance early helps guide a switch to a different treatment approach before the infection gets worse.

What genes does this test look at and why?

This test examines the UL97, UL54, and UL56 genes, which are the parts of the CMV virus that antiviral drugs target. Mutations in UL97 commonly cause resistance to Ganciclovir, while UL54 mutations can affect multiple drugs including Foscarnet and Cidofovir. UL56 mutations are linked to resistance against Letermovir, so checking all three genes gives a fuller picture of which treatments will still work.

What does a positive resistance mutation result mean?

A positive result means the CMV virus in your body has a genetic change that can make one or more antiviral drugs less effective. This doesn't mean all treatment options are gone — it simply points toward switching to a different antiviral that isn't affected by that specific mutation. Because CMV infection can be serious, especially in people with weakened immune systems, abnormal results should be acted on quickly with adjusted treatment.

What causes CMV to develop drug resistance?

Drug resistance usually develops when CMV is exposed to antiviral medication for a long period, especially in people who need extended treatment due to weakened immune systems. Inconsistent dosing, low medication levels in the body, or a high starting viral load can also give the virus more chances to mutate. The longer active CMV replication continues during treatment, the higher the chance resistance mutations appear.

How often should I retest for CMV resistance?

Retesting is typically considered when your viral load isn't dropping after a few weeks of antiviral treatment, or if symptoms return after initially improving. Your care plan may call for repeat viral load checks every 1-2 weeks during active treatment, with resistance testing triggered by lack of response. Tracking your results over time in your account can help spot patterns that suggest resistance is developing.

What should I do if my results show resistance?

If your results show a resistance mutation, the next step is usually switching to an antiviral drug that isn't affected by that specific genetic change. Keep track of your viral load and symptoms closely during this transition, since treatment response can take time to show up. If symptoms are severe or worsening, such as high fever, vision changes, or difficulty breathing, seek medical care right away.

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.

CMV Genotype Test - Antiviral Drug Resistance 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

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