For those of you who are slightly squeamish, unless you have pets & should read this, feel free to skip my post.
Earlier I mentioned Sherlock had been biting at an area on his hip or backside, on the left side to be precise. We couldn't find anything & I suspect the redness is due to the biting, not the biting from the redness. The vet said sometimes that spot on the body is due to itching, irritation & a plugged anal sack. Sure enough his left sack was slightly plugged & enlarged. She took care of the problem & will recheck it in two weeks. For his skin we have an antibiotic powder to use.