dear doc my brother is having low grade fever in the late evening almost from one month, for one week there was no fever.He does not have wt. loss and loss of appetite ,a little bit tendonitis is present.all investigations are negtive like TB PCR , HIV ,HBS Ag,RA FACTOR,ANA,COMPLETE HEMOGRAM,WIDAL,MP,LFT,RFTetc.what should we do now