A friend later told me that MRSA sometimes mimics the same symptoms, but both occurred during summer, and not around other kids or in a hospital setting.
Unfortunately doctors tend to over diagnose a lot of things as brown recluse bites[1]. So, unless he specifically tested for it, there's a really good chance it wasn't a brown recluse bite.
Funny. 10 years ago, I lived at the northern edge of the brown recluse zone. I saw many spiders in my apartment building that looked like them - can't say for sure. Then one day I developed sudden swelling on my thigh. It went from nothing to fairly swollen in about 2 hours.
I went to the doctor and he said "Could be a spider bite, or could be a staph infection. No way to know - just take these antibiotics and pray."
Then earlier this year it happened again - at a similar spot. Doctor said the same thing. No brown recluses in this area, but he said it could be a different spider.
A friend later told me that MRSA sometimes mimics the same symptoms, but both occurred during summer, and not around other kids or in a hospital setting.