Rash Side of Knee

Recently my wife and I noticed some rashes or bug bites on our two little girls, ages 5 and 3.  They appeared on their legs and were red with a skin tone center and very hard to the touch.  At first we figured they might be spider bites that they just got during the night.  The next day we drove to another state to visit family and figured if they were from a spider or something in their bed then they would just go away.  After spending the night in another state they both again woke up with bites on different areas on their legs.  The others went away during the night and the new ones disappeared during the day, but then we noticed that the five year old had another rash-like red area on the side of her right knee.  It has gotten bigger throughout the day and is currently about the size of a baseball and has spread to the back of the knee.  The borders are not well defined, there is no pain, no itching and no dryness.  The area is raised a little bit, and not hard to the touch.  The 3 year old has no such rash on her.  I'm assuming that since there aren't any other symptoms its probably nothing, but I wanted to check and see if someone else agreed.

[Vanessa Lacuesta]

Hi

I would suggest that blood tests be done to determine what caused the skin condition. This may be caused by a bacterial or a viral infection. Insect bites or tick bites should also be considered. A blood test such as CBC or complete blood count may be requested. Urinalysis may also be requested to determine the focus of infection as kidney problems may present with skin problems. As there is no pain and no itching, this may not be case of dermatitis. A viral infection may appear to be likely.