Yes, her joints swelled up so bad that she couldn't walk. With Mia, the joints swelling up actually happpened as she was being diagnosed with Erlichea, so it was pretty much all at the same time and she stopped eating/drinking right around then so we were also dealing with dehydration.
She also had a weird head weaving thing, almost like she was dizzy and she would walk in circles and then fall down. The vet said this was also probably related to the immune response.
I don't remember her Doxy dosage, but in the beginning, she was on 40mg of Pred per day and we have now weaned her down to 5mg every other day, we just can't take her completely off of the pred because the head weaving thing comes back and her joints start to swell again.
The bumps showed up when she was on pred and Imizol at the same time, the vet reduced the dosage of both medications and the bumps went away. The theory was that the 2 meds in combination were reducing her immune system TOO much so that is why the bumps showed up.
The good news is once we got Mia completely stablized, she has been fine for 3 years now. Those first few months were scary, but she is doing great, she is happy, playful, and she eats great.