What is this rash and swelling on my one-year-old daughter?

June 7, 2009 6:17 PM

Diagnose my daughter's come-and-go, non-itchy rash and swelling.

About 24 hours ago, my 1-year-old daughter awoke from a nap. She had a bright red cheek, red upper arm and a round red spot, about 2" in diameter, on the back of her thigh--all on the left side of her body. The cheek had a line of tiny white dots which, over the course of the next 30 minutes, grew into one big welt which was white. The arm rash developed a white raised border. The thigh spot was raised but in the way that you can get swollen when you have a bruise--plus, the coloration of this spot was slightly purply.

No fever, no vomiting, no other symptoms. She didn't eat anything out of her usual routine. She had not been introduced to anything new including animals or detergents. I could not find any evidence of bug or spider bite. And she wasn't scratching at all.

Per the pediatrician, we gave Benadryl which took care of the cheek and arm but not the thigh. She was acting normally so I put her to bed.

Come this morning, she woke up all swollen--but on the opposite side. Her right half of her face, upper arm and leg were all swollen. And with no rash.

Took her to the local children's hospital urgent care. The pediatrician there suggested it could be serum sickness but did not really explain what that is other than a rash, malaise, fever, joint pain, etc. from a list of about 1000000 causes. She did a rapid strep test, which was negative--this will also be cultured.

So when I got home, I Googled serum sickness. My daughter had a course of cipro eye drops for pinkeye about 10 days ago. So that is a distinct possibility.

In the past month, she's also had: roseola (also had a febrile seizure due to high fever preceeding the roseola rash), fifth disease, pinkeye and a cold. (During her birthday, no less!)

During the course of today, she's been fine--swelling has gone down. But, upon waking from her afternoon nap, she had a bright red spot on the very top of her head, plus she had a rash with a raised border on each of her shoulders. The red spot went away with another dose of Benadryl.

So... my question is, what do YOU think this could be? Does anyone have any other ideas? Have you had any experience with serum sickness, especially in young children? She's not acting out of sorts, and she's still not itching. What gives???

posted by FergieBelle to health & fitness (5 comments total)

(I am neither a doctor nor a parent) From your description, it sounds like she might be allergic to something she's lying on in her crib or bed, since the swelling appears when she wakes up, and is along one side of her body -- like the side she slept on. Have you changed detergents lately? Sprayed her crib with Febreeze, or used a new room freshener? Try washing all her clothes and bedding in fragrance-free detergent.
posted by junkbox at 8:05 PM on June 7

IANAD but I'm a parent and ditto junkbox -- find something totally different for her to lie on, preferably cotton. And make sure it hasn't been washed with anything odd, no fabric softener or anything like that (but not new-from-the-shop either -- there's all kids of strange chemicals used on new fabric.)

Not-quite-to-the-point anecdote: when we move to the US our daughter was two. She developed a very very itchy rash, for half a year, that was soothed only by bathing in cool water. We never discovered the cause but eventually it went away. She's in her 20s now (and starting at med school in the fall, yay!)
posted by anadem at 8:27 PM on June 7

I immediately thought of Fifth disease when I read your lead-in, but since you've already seen and had that diagnosed, I'm going to have to lean towards the idea of soaps and detergents like the junkbox and anadem suggest.

It could be that the fifth disease is still present, or just running a second course, and the other irritant is making it seem worse. Try out fragrance/allergen free sensitive skin detergents and see what improves. Best of luck.
posted by Kimothy at 9:31 PM on June 7

Update: Overnight, it appears she threw up. And now she's got diarrhea. Oh, the joys of parenting.

I will let you all know if, after discussing this with her regular doctor, any new ideas come about.

Thank you everyone for your ideas. I already use fragrance/dye-free detergent for all laundry. I know that allergies can crop up out of nowhere, and the fact that it's pretty much one-sided at a time leads to the allergy theory.
posted by FergieBelle at 5:14 AM on June 8

Kimothy: I asked the doctor if one of her viral rash diseases (either roseola or fifth) could be re-activated, and she said she'd never heard of that. The rash is not like the typical fifth disease rash, and there's no fever.
posted by FergieBelle at 5:15 AM on June 8