Persistent fever with chills. occasionally cough with vomiting when fever happens. No bacteria found in blood culture. Tlc count fluctuating between 25000 to 11800. Bone marrow and lymph node biopsy done to trace cause of fever. Antibiotics on. Diarrhea happened .platletdecreased. Fever happened. Sudden fall in bp and heart beat 135. Shifted to icu. Why is it happening inspite of use of meropenem. Tigeracyclin.and other heavy antibiotics. What is the problem.