Recruited participants will randomly be assigned to either receive the study drugs of Meropenem or Piperacillin-Tazobactam in a 1:1 ratio according to a randomisation list prepared in advance. The intervention treatment for this study is the administration of the drug Piperacillin-Tazobactam 4.5 grams administered every 6 hours intravenously over a 30 minute period. The duration of treatment with this drug will be for a minimum of 4 days and a maximum of 14 days. The duration of the therapy will