Contemporary antimicrobial susceptibility patterns of bacterial pathogens commonly associated with febrile patients with neutropenia.

One of the most challenging problems in antimicrobial chemotherapy is the effective empirical treatment of infection in patients with neutropenia. The rates of occurrence for pathogens have significantly changed (from predominance of gram-negative to gram-positive organisms) under selective pressure of broad-spectrum antimicrobial therapy or prophylaxis, and novel resistance mechanisms have emerged. To address the need for appropriate monotherapy or combination regimens for patients with neutropenia, physicians must prescribe agents with a spectrum of antimicrobial activity to inhibit the major, prevalent pathogens encountered in bloodstream infection and pneumonia; in addition, these selected agents must be active against recently described resistant organisms. Data from the SENTRY Antimicrobial Surveillance Program indicate that several broad-spectrum agents remain highly active and can be used alone or in combinations. In most cases, the newer compounds with increased activity and spectrum against gram-positive cocci (i.e., carbapenems, cefepime, levofloxacin, and trovafloxacin) offer a greater inhibitory potential for empirical therapy among patients with neutropenia and severe infections.