Impact of Antimicrobial Resistance on the Treatment of Invasive Pneumococcal Infections.

Infectious diseases, such as pneumococcal pneumonia, which were almost invariably lethal in the pre-antibiotic era, caused radically less mortality with the advent of antimicrobial chemotherapy. However, the use, misuse, and abuse of these agents have led to the emergence of antimicrobial resistance. In the past, pneumococci were all exquisitely sensitive to penicillin G. By the late 1960s, penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) was being described. Since then, this problem has achieved epidemic proportions in many areas of the world, including the United States. Many experts no longer consider penicillin an acceptable therapy for patients suspected of having invasive pneumococcal disease, especially if the central nervous system (CNS) is involved. Recommendations for therapy are based on theoretical concerns, in vitro susceptibility testing, animal data, and a few, scattered reports of penicillin failure in patients with invasive disease.