I wouldn't expect that to be from Altace. The only way to be absolutely certain would be to do a trial without Altace and see if your condition improves. Of course, you should always check with your doctor, right?
Is Altace the only drug you are on? Were you on Altace before or after you got really sick? Also, are you sure that these problems aren't a result from you being sick? Perhaps you are still sick? CFIDS comes to mind.