Fort Worth, Texas,
09:12 AM

5 days of fever, now what should I do?

Kawasaki and other fevers

I have used a lot of words to tell you not to worry about fever. Fever is your child’s friend. Don’t go to the ER for fever alone. Don’t buy all the fever myths out there.

When should you be worried? The biggest issue is context. You can read the other posts to see all about that.

Another reason you should be more concerned with fever is if it is lasting more than 5 days. Of course, if you end up with a diagnosis where fever is known to last more then 5 days, no big deal, but otherwise, most fevers should be gone by then.

This situation is called fever without a source.

There are many different definitions of fever without a source but I use: fever greater than 101 for eight days in a child in whom there is no obvious source of the fever through the patient’s story or physical exam.

Because children can often have back-to-back viral infections, it is important that this fever be present daily or near daily. For instance, it doesn’t count if they had fever for 3 days then were better for 2 days and then had fever again for 3 days.

The different things to think about are all over the place and can range from very serious to the “no-big-deal.”

Infections - The most common diagnosis in this instance is “unknown” but the fever goes away on its own. While often not intellectually satisfying (to either me or the parent who wants to know what is going on), this is probably the best outcome for the patient. Most of those are probably viruses for which we don’t have or don’t think to run specific tests. Bacterial infections can also cause long-standing fever.

Rheumatologic - Less commonly, children with prolonged fever can have rheumatologic causes, an example is juvenile rheumatoid arthritis. Often these children will have exam findings like swollen, painful joints or swollen lymph nodes that will help point towards their diagnosis.

Malignancy - Fortunately, this is a very rare cause of prolonged fever but it does happen so we all need to keep it in the back of our mind. The most common type of cancer in children is leukemia.

The workup for fever without a source involves a few things:

  1. Repeat histories and physical exams - Often things are discovered over time.
  2. Preliminary screening labs - Check these in just about all kids with it.
  3. Specific tailored labs and exams - Check some of these based on a child’s story or exam.

Kawasaki disease

One specific cause of fever over five days deserves specific attention. Because many parents are not aware of it and because the diagnosis can be tricky, I thought it deserved its own specific mentions.

Kawasaki disease (KD) is characterized by the characteristic fever over 5 days along with some of the following findings:

  • Swelling or redness of the hands and feet, followed by peeling of the tips of the toes or fingers
  • Red rash all over
  • Redness and crusting of the lips or redness of the tongue (like a strawberry)
  • Severe pink eye
  • Swollen lymph nodes of the neck

One of the other things to note with KD is that these children are very, very irritable. Not kinda irritable, but noticeably irritable even to a pediatrician who hears crying babies and children all day long irritable.

The cause of KD is unknown. There is some evidence to suggest that there might be an infection involved. The symptoms and complications associated with it are a result of inflammation of small to medium sized arteries throughout the body.

The most commonly known complications of KD involve the heart and can be inflammation or the lining or muscles of the heart or dilation of the arteries that supply the heart.

If you suspect your child has KD it is important to seek your doctor’s advice quickly, as it is much easier for your physician to connect the dots when symptoms are present. Blood tests can help confirm the diagnosis and treatment can resolve the symptoms and help to prevent complications.

The good news is that children with Kawasaki's disease, like the child in the photos with this blog, usually return to normal and don't suffer complications.

Get to know Justin Smith, M.D.

Justin Smith, M.D., is a pediatrician in Trophy Club  and the Medical Advisor for Digital Health for Cook Children's in Fort Worth, Texas. Dr. Smith is an experienced keynote speaker for a variety of topics including pediatric/parenting topics, healthcare social media and physician leadership. If you are interested in having Dr. Smith present to your conference or meeting, please contact him at

He has an active community on both Facebook and Twitter as @TheDocSmitty and writes weekly for Cook Children's He believes that strategic use of social media and technology by pediatricians to connect with families can deepen their relationship and provide a new level of convenience for both of their busy lifestyles. Dr. Smith’s innovative pediatric clinic, a pediatric clinic “designed by you,” open now. Click here to make an appointment, call 817-347-8100.


Comments 1 - 7 (7)
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Tarah Bauder
My daughter was tested for strep last Friday and the test came back negative but the dr seemed like she still may have it and put her on penicilan, her fever finally broke on Monday morning but now is back today and she has a cough and red boogery eyes. im concerned as to why her fever isn't going away for good
this is very helpul. thanx
Julie phillips
I am at my wit's end with my son's illness. Two years + he's had FUO. Started as 1-3 days bimonthly 101.4 fever always. 1 year ago episodes starting lasting 3-5 weeks same temp. he has been to many specialist lots of blood work. Not Lupus, Lyme disease, Allergies, RA, Aids, Crohns, parasites or brain tumor.
Justin Smith, M.D.
I suggest that you notify the doctor and/or specialist who is treating her to let them know she is not responding. We do sometimes require longer treatment with antibiotics for more complicated infections.Thank you and good luck.
Good day Dr, my daugther, age 12, is diagnosed with Tonsilitis. Dr put her on 2 different antibiotics after several visits since 3/01/2017. She doesnt get beter. The fever has not broke. At night we cant sleep at all!! She's booked for surgery for early May 2017. In the meantime, what can we do? She cant swallow, earaches, sleepy due to the medication she taking. Is it a good thing to be on antibiotics for almost 2weeks?
Justin Smith
Hello Elma,

It depends on the type of infection. I would talk with your doctor about getting the right testing and the right antibiotic for you child.

Thank you,
Dr. Smith
Elma Eugenio
What kind of anti-biotic or medicine should i give to my child having a urinary track infection...and a fever in 5 days?