Q: My 33-month-old has frequent bronchitis, high inflammation, and an aPTT of 62.0. Can fever cause high aPTT?
Updated: Sep 7
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:
My 33-month-old child has had frequent viral infections with high inflammation markers and has been hospitalized six times. The diagnosis is always recurrent bronchitis, and their lung condition neither improves nor worsens; it just stays the same. The fever drops after steroid administration, and a recent immune function test came back normal.
Recently, a blood test showed my child's aPTT level was 62.0. Can this level rise temporarily just because of a fever? The doctors at our local secondary hospital say my child gets sick often simply because they are young. Is an aPTT blood coagulation test result of 62.0 okay?
Answer:
Going through six hospitalizations with your 33-month-old must have been incredibly exhausting and stressful for your family.
Based on your description, here is a breakdown of your child's current medical situation and what steps you should take next:
Can a fever alone cause an aPTT of 62.0?
An aPTT (Activated Partial Thromboplastin Time) of 62.0 seconds is prolonged, as the normal upper limit is typically around 35 to 40 seconds. It is rare for a fever itself to cause the aPTT to rise to 62 seconds.
Common causes for a prolonged aPTT include:
Technical errors during the blood draw (such as dilution or improper clotting in the sample tube).
Deficiencies in coagulation factors (such as hemophilia) or the presence of lupus anticoagulant.
Decreased liver function or Vitamin K deficiency.
The use of certain medications or anticoagulants (like Heparin).
Because a result of 62.0 is elevated, a retest and further clinical evaluation are necessary to determine the exact cause.
Recurrent Infections and Steroid Response
Although your child's immune function tests were normal, a pattern of recurrent bronchitis that responds well to steroids suggests a few other possibilities that go beyond "just being young":
Early-stage asthma (bronchial hyperreactivity): Since the fever and symptoms improve with steroids, an underlying asthma tendency should be strongly considered.
Structural issues: Such as airway narrowing or tracheobronchomalacia (weakness of the airway walls).
Rare conditions: Such as primary ciliary dyskinesia or cystic fibrosis.
Actionable Guidance for Your Next Doctor's Visit:
We highly recommend following up with your pediatrician for a deeper evaluation. When you go, be sure to ask the doctor the following specific questions:
"Given the prolonged aPTT of 62.0 seconds, do we need to schedule a retest or get a referral to a pediatric hematologist?"
"Considering the recurrent bronchitis and the positive response to steroids, is there a possibility this could be pediatric asthma?"
Warning Signs Requiring Immediate Medical Attention:
Please seek emergency care immediately if your child experiences any of the following symptoms before your next appointment:
Blue lips or fingernails (cyanosis), or severe shortness of breath where the skin pulls in deeply under the ribs.
New or worsening bruising, nosebleeds, or bleeding gums (which can be tied to coagulation issues).
Repeated vomiting or no urine output for more than 8 hours.
A fever of 38.0°C (100.4°F) or higher accompanied by severe lethargy or unresponsiveness.
For extra peace of mind and clear guidance when tracking your child's symptoms, the FeverCoach app is always there to help.
