a 10 yrs old boy admitted with complaint of high grade fever with chills (105) for 5-6 days after inj ceftriaxone and inj amikacin came fown to 102 then again started going upto 103 .He has just palpable firm spleen .His cbc,-wnl  MP card, typhi dot,  negative ,scrub- Negative , LFT WNL,URINE shows 6-8  RBC/HPF pus cells 2-3/hpf  rest NAD,, how to approach when fever is not coming down after giving inj cef trixone and inj amik cin