Q: Is it normal for my child to undergo multiple tests for respiratory viruses and Mycoplasma?
- Myeongchan Kim, MD
- 1 day ago
- 2 min read
Medically reviewed by Sang Hyun Ahn, MD
Content edited by Myeongchan Kim, MD
This post is a dramatization of a question and answer session experienced by our actual medical reviewers. Please note that this content is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.
Question:
First of all, thank you as always! On Monday morning, my child had a blood test for inflammation markers and was sent home for outpatient treatment. However, by the evening, their croup worsened, and my child had to be hospitalized due to difficulty breathing.
They did a nasal swab for respiratory viruses and drew blood when inserting the IV. The doctor said it was RSV. However, since my child wasn't improving, the doctor suspected Mycoplasma and did another nasal swab yesterday (a basic state-covered one), which came back negative. Today, while changing the IV site, they drew blood again to specifically test for Mycoplasma.
Is it normal to undergo this many tests? Do Mycoplasma and RSV not show up together on the initial respiratory test?
Answer:
You must be very worried, especially since your child had to be hospitalized for difficulty breathing. Let me explain the respiratory testing process and why this is happening.
Why multiple tests are necessary:
Different types of pathogens: There are many types of respiratory viruses, such as RSV, Influenza, COVID-19, and Adenovirus.
Viruses vs. Bacteria: Mycoplasma is a bacterium, not a virus. While some comprehensive multiplex PCR swab panels test for it, it often requires a separate test (like a blood test for antibodies) to accurately diagnose.
False negatives: In the early stages of an infection, tests can sometimes yield negative results even if the pathogen is present.
Different testing methods: Nasal swabs are typically used to detect viral antigens or DNA/RNA, while blood tests are often used to check the body's immune response (antibodies) to Mycoplasma.
Regarding your current situation:
This sequence of testing is completely normal and appropriate. Your child was initially confirmed to have RSV. However, because your child was not showing clinical improvement with standard supportive care, it is crucial for the medical team to look for other pathogens, such as Mycoplasma, which can often occur as a co-infection.
Because a Mycoplasma infection requires specific types of antibiotics (unlike RSV, which is a virus and cannot be treated with antibiotics), getting an accurate diagnosis through an additional blood test is a very careful and necessary step by your medical team.
What you should monitor as a parent:
Watch closely to see if your child's breathing becomes more comfortable.
Monitor whether the fever is starting to go down.
It sounds like your medical team is taking a very thorough approach to ensure your child gets the correct treatment. Please feel free to ask your attending physician for a detailed explanation of these new test results and the ongoing treatment plan.
For extra peace of mind and clear guidance when tracking your child's symptoms, the FeverCoach app is always there to help.
