Penicillin Failure in the Treatment of Acute and Relapsing Tonsillopharyngitis Is Associated With Copathogens and Alteration of Microbial Balance: A Role for Cephalosporins

The causes of penicillin failure in eradicating group A β-hemolytic streptococcal (GABHS) pharyngotonsillitis that are due to microbiological interactions are described. These include the presence of β-lactamase— producing bacteria that protect GABHS from penicillins, the absence of bacteria that interfere with the growth of GABHS, and coaggregation between GABHS and Moraxella catarrhalis. Antimicrobials that can overcome and modulate these phenomena achieve better cure of the infection than penicillins. The agents more effective than penicillins in the treatment of acute infections included the cephalosporins and macrolides, and those more effective in the treatment of chronic infections included clindamycin and amoxicillin-clavulanate.