Is there any chance this is a Lyme rash?

DS normally has eczema, and he developed a circular rash on the back of his thigh in late June. We put his usual aclovate ointment on it, but it didn't go away. By late August, it was quite a bit darker, so we took him to see a PA at the allergist's office. The PA thought it might be fungal. He prescribed an antifungal cream to be used for two weeks.

Well, it's two weeks later, and the rash has now spread down DS's leg. I've attached a photo.

We're taking him to our primary care physician as soon as we can get him in, but I googled tonight, and am now wondering: Is there any chance this is a Lyme rash?

We did a fair amount of camping this summer, but I never saw any ticks.

[Carol in PA]

You can find a number of Lyme rash pictures to compare yours to, at the Canadian Lyme disease Foundation.
Canadian Lyme Disease Foundation, canlyme (dotcom)
Click on Symptoms, then click on "the Lyme rash."

Carol