Question 1

What is Serum Sickness?

Accepted Answer

Serum sickness is a delayed allergic reaction that occurs 1-3 weeks after exposure to certain medications or proteins. It is caused by immune complexes forming when antibodies bind to drug molecules, triggering widespread inflammation in blood vessels, joints, and tissues. The BasoFunction HRT Penicillin (Minor Det) test is the most important test for diagnosing penicillin-induced serum sickness because it measures specific immune response biomarkers that remain elevated during active drug allergy reactions.

Question 2

What causes serum sickness?

Accepted Answer

Serum sickness is caused by immune complexes that form when your body produces antibodies against foreign proteins or medications. The most common triggers include antibiotics like penicillin and cefaclor, antiseizure medications, antivenom treatments, and certain biologic drugs. When these substances enter your bloodstream, your immune system may recognize them as threats and create antibodies that bind to the drug molecules, forming immune complexes that deposit in blood vessel walls, joints, and other tissues, causing widespread inflammation throughout your body.

Question 3

What is the best test for serum sickness?

Accepted Answer

The BasoFunction HRT Penicillin (Minor Det) test is the most important test for penicillin-induced serum sickness because it measures specific immune response biomarkers that remain elevated during active allergic reactions. This specialized test detects basophil activation and histamine release triggered by penicillin metabolites, which distinguishes delayed serum sickness reactions from immediate allergies. The test is particularly valuable when symptoms appear 1-3 weeks after medication exposure, as it can confirm that your immune system is still actively reacting to the drug even after you've stopped taking it.

Question 4

When should I get tested for serum sickness?

Accepted Answer

You should get tested if you develop fever, rash, joint pain, or swollen lymph nodes 1-3 weeks after starting a new medication, especially antibiotics like penicillin. Testing is particularly important if you've recently received antivenom, monoclonal antibody treatments, or antiseizure drugs and begin experiencing these delayed symptoms. Early testing helps distinguish serum sickness from other conditions with similar symptoms and guides your doctor in adjusting your treatment plan to prevent complications.

Question 5

What are the symptoms of serum sickness?

Accepted Answer

Serum sickness symptoms typically appear 7-21 days after exposure to the triggering medication and include fever ranging from 100-104°F, itchy rash that often starts where the medication was injected or taken, painful and swollen joints especially in the hands and knees, swollen lymph nodes particularly in the neck and armpits, fatigue and general feeling of being unwell, headaches, and sometimes abdominal pain with nausea. The rash may appear as red patches, hives, or raised bumps and can spread across your entire body.

Question 6

Who is at risk for serum sickness?

Accepted Answer

Anyone taking medications that commonly trigger serum sickness is at risk, particularly those prescribed penicillin, cephalosporin antibiotics, sulfa drugs, or antiseizure medications like phenytoin. People receiving antivenom after snake or spider bites face higher risk, as do patients treated with monoclonal antibodies or certain biologic medications. Children and young adults appear more susceptible than older adults, and having a history of drug allergies or autoimmune conditions may increase your likelihood of developing serum sickness when exposed to triggering substances.

Question 7

What happens if serum sickness is left untreated?

Accepted Answer

Untreated serum sickness can lead to serious complications including kidney inflammation (glomerulonephritis) that may cause permanent kidney damage, inflammation of blood vessels (vasculitis) affecting multiple organs, heart inflammation (myocarditis or pericarditis) causing chest pain and breathing difficulties, and nerve damage resulting in numbness or weakness. While most cases resolve within a few weeks even without treatment, severe reactions can cause life-threatening organ damage. Early diagnosis and treatment with corticosteroids significantly reduces the risk of these complications and speeds recovery.

Question 8

Can serum sickness be diagnosed with a blood test?

Accepted Answer

Yes, serum sickness can be diagnosed with specialized blood tests that detect immune system activation and drug-specific antibodies. The BasoFunction HRT Penicillin test measures basophil activation and immune responses specific to penicillin sensitivity, which helps confirm delayed allergic reactions. Additional blood tests may show elevated inflammatory markers, increased eosinophils (a type of white blood cell), low complement levels (proteins involved in immune responses), and sometimes antibodies against the triggering medication. These tests combined with your symptom timeline and medication history provide strong evidence for serum sickness diagnosis.

Question 9

How is serum sickness treated?

Accepted Answer

Serum sickness treatment begins with immediately stopping the medication or substance that triggered the reaction. Your doctor will typically prescribe antihistamines like diphenhydramine to reduce itching and rash, nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen for joint pain and fever, and corticosteroids like prednisone for moderate to severe cases to reduce immune system activity and inflammation. Most people recover completely within 2-4 weeks with appropriate treatment, though symptoms may persist longer in severe cases. Your healthcare provider will monitor your kidney function and other organ systems during recovery.

Question 10

How can I prevent serum sickness?

Accepted Answer

Prevention focuses on avoiding medications that previously caused serum sickness reactions and informing all healthcare providers about your drug allergy history. Always wear a medical alert bracelet or carry a card listing medications you cannot take, especially if you've had serum sickness from penicillin or other common drugs. When prescribed new medications, ask your doctor about alternatives if you have a history of drug allergies. If you require antivenom or other high-risk treatments, your medical team can premedicate you with antihistamines and corticosteroids to reduce the likelihood of developing serum sickness.

Question 11

What can I do at home for serum sickness symptoms?

Accepted Answer

At home, you can manage mild serum sickness symptoms by taking cool oatmeal baths to soothe itchy skin, applying cold compresses to swollen joints, drinking plenty of fluids to stay hydrated and support kidney function, and resting to help your body recover. Over-the-counter antihistamines can reduce itching, while acetaminophen helps with fever and discomfort if you cannot take NSAIDs. Keep a symptom diary noting any worsening signs like increased swelling, breathing difficulties, or decreased urination, which require immediate medical attention. Avoid the triggering medication and any chemically similar drugs until you've consulted with your healthcare provider.

Question 12

How’s this work?

Accepted Answer

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.

Question 13

How do I know which test to get?

Accepted Answer

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.

Question 14

When will my lab results be available?

Accepted Answer

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.

Question 15

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?

Accepted Answer

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.

Question 16

Do you accept health insurance?

Accepted Answer

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.

Question 17

Can I cancel my order?

Accepted Answer

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.

Question 18

How can I find a lab location near me?

Accepted Answer

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.

Serum Sickness Blood Test

What is Serum Sickness?

What causes serum sickness?

What is the best test for serum sickness?

When should I get tested for serum sickness?

References

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