I am a hypothyroid patient from almost 5 years.i get these evening fevers ranging between 99.1-.4 every alternative day.i don t feel feverish most of the times but when i measure the temperature i have this fever.i had thyroditis 4 years back. and then again last year.where i ran these fevers. these fevers keep coming back. i have got all my basic tests done,including tb,diabetes,lft,kft. my esr usually stays elevated and my tlc was 11300.rest everything came back pretty normal.what could be the cause.