Aztreonam in the prevention and treatment of infection in neutropenic cancer patients.

The treatment of bacterial infections in neutropenic cancer patients presents a serious challenge to physicians. Although gram-positive infections have become more common in recent years, most infections in this population are caused by gram-negative bacilli. No single regimen has been found to be optimal, and most commonly used regimens are associated with significant disadvantages. Extensive investigation is therefore under way to evaluate the potential of several promising newer antimicrobial agents. Aztreonam, for example, is active against most gram-negative pathogenic bacteria and has been evaluated in several clinical trials in neutropenic patients. As the only agent with gram-negative activity or in combination either with aminoglycosides or with other beta-lactam antibiotics, aztreonam proved useful in the treatment of gram-negative infections in this population. Combination with an aminoglycoside, however, was not found to improve efficacy over aztreonam alone. In fact, since aminoglycosides may potentiate ototoxicity and nephrotoxicity, it may be more appropriate to replace the aminoglycoside component of a combination regimen with aztreonam, as indicated by data from a study of aztreonam plus cefoperazone. Aztreonam selectively inhibits the aerobic gram-negative intestinal flora with only minimal disruption of anaerobic flora, and may be useful for infection prevention, but the importance of anaerobic preservation is not clear. It was concluded that aztreonam appears to be a useful agent for the treatment of febrile neutropenic patients, but further study is recommended.