Hi
I am sorry your little girl is having more problems.
There are so many adverse reactions caused by immunosuppressive treatment that can be mistaken for the return of an AI disease. The natural reaction is to increase the medication to further suppress the immune system - but this is not always the best path to take.
Generally, if a limp is on one leg or paw only then it will not be due to an inflammatory AI disease process and it is very likely to be caused by the effects of the medication, whether it be due to stretched ligaments or tendons, muscle loss or a sprain injury. Likewise, many dogs who have been on prolonged immunosuppressive therapy get skin problems, in the form of nodules and lesions etc., due to inflammation and thin skin. Cutaneous vasculitis is quite common and this can show in a variety of different forms.
I would ask your specialist if he or she is absolutely sure that the symptoms you are seeing are due to IMPA, or if the medication she has been on for a long while may be causing, or at least contributing to, the clinical signs you are seeing. Often the best course of action is to lower the dose to see if the symptoms improve. If a dog has been on immunosuppressive treatment for many months it is unlikely that the AI disease will still be very active. The 'heavy' drugs used to bring the disease under control are necessary but when the dog has been on them for a long while the drugs can cause more problems than the disease itself. It is just something to consider.
I do hope your see an improvement very soon.
Jo