Campath and Low Grade Fever

[Low Fever]

I have been treated for MS since 2002. I first used Betaseron and then
in 2010 I switched to Gilenya. During this time I had bouts of fever,
about 2 months apart, which were caused by urinary tract infections
due to catheterisation. These fevers were easily controlled by a
combination of Tylenol and Motrin until the fever went away after
about 6 hours.

I stopped Gilenya and was infused with Campath in the first week of
March this year. Around ten days ago I started getting fevers every
day of between 99.9F and 101.4F. When I have these fevers the
spacticity in my legs gets very strong and my legs go completely rigid
and painful, my hands also get painful and I get a headache. These
fevers start every day at around 1-2pm and end by themselves at around
9-10pm. Tylenol and Motrin have no effect on these fevers. I can only
go to bed and ride it out, not even able to get up and use the
bathroom or go to the kitchen to feed myself.

My local doctor has checked for infections which could cause the
fevers and has found none. My Neurologist (who administered the
Campath) cannot find a reason and says that these symptoms have never
been seen before in Campath patients. The nurse practitioner suggested
that I use a cooling jacket or sit in a cold shower for 30 minutes to
keep the fever down.

I don't want to spend the rest of my life flat on my back, in pain
needing a full time carer or sitting in a cold shower.

Can anyone suggest what is causing the fevers?