Poor kid. If he looked sick, I'd have taken him to the doctor. His only symptom was rash that, over the course of a week, spread from his chest to his back, shoulders, and then started to creep down his legs. Tiny bumps (papules) bright pink initially but fading so that you couldn't see them well at all any more. He knew they were there, though.
And they itched. Not that I wasn't sympathetic, but he only seemed to itch at bedtime. So we tried benadryl -- at least he could sleep. He probably itched the rest of the day, but he was too busy to complain. He's always doing something.
Besides, I figured self-limiting, probably viral. Not much point in going to the doctor for that. But it wasn't my rash and he insisted. So we went.
Funny thing is I was only wrong on one point. The pediatrician called it exanthem (aka exanthum) -- IOW, itchy rash, probably viral in origin. He did do a throat culture to rule out Strep, but he thought that was unlikely. Solution, atarax to help control the itching until it goes away in a few more days.
The culture was negative. He's still bumpy and itchy, but at least he believes someone cares. Maybe not his mother, but at least his pediatrician does.