This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
A man had infection with Extended spectrum betalactamase (ESBL) Klebsiela pneumonae is staed with cefotaxim plus amikacin therapy. On culture sensitivity after 48 hrs ESBL Klebsiela were found. Which of the following would be the best next course of action? 
Select and explain. 
A. Continue with same antibiotic but in higher dose, B. Change ceftriaxone to ceftazidime, C. Sta imipenem therapy in place of ceftriaxone, D. Change Amikacin to Quinolones
C: Sta imipenem therapy in place of ceftriaxone
Answer: C: Sta imipenem therapy in place of ceftriaxone 
Explanation: Ans. is 'c' i.e., Sta imipenem therapy in place of ceftriaxone Carbapenems like imipenem are the only beta lactams reliably efficacious against ESBL producing bacteria. Drugs used for ESBL producing bacteria are: A) beta-lactamase inhibitor combination o Clavulinic acid +Amoxcillin Clavulanic acid + Ticarcillin o Sulbactam + ampicillin o Tazobactam + piperacillin B) Cefamycins Cefoxitin, Cefotetan Carbapenems : Imipenem, meropenem