My pup also got Lyme disease. I thought it was the end, but she recovered so well and we got a few more years together. She was an English bulldog, so a few more years for them is a lot. I know bloodwork is a pain and pricey, but absolutely monitor his kidneys over time, keeping on top of kidney function with Lyme is super helpful. Even when the kidney values are low, there’s prescription diets that can help with everything. (I worked in vet medicine too, so know these things.)