Four reasons justify the undertaking of this study ; firstly , the cut-off points which determine whether a pneumococcus is susceptible or resistant to penicillin have changed in 2008 and according to some studies published recently the pneumococcal resistances to penicillin in Spain have fallen drastically , with only 0.9 % of the strains being resistant to oral penicillin ( minimum inhibitory concentration > 2g/ml ) ; secondly , there is no correlation between pneumococcal infection by a strain resistant to penicillin and therapeutic failure in pneumonia ; thirdly , the use of narrow-spectrum antibiotics is urgently needed because of the dearth of new antimicrobials and the link observed between consumption of broad-spectrum antibiotics and emergence and spread of antibacterial resistance ; and fourthly , no clinical study comparing amoxicillin and penicillin V in pneumonia in adults has been published .
