ABSTRACT

Many cancer treatment centers have documented a decline in the proportion of bacterial infections caused by aerobic gram-negative bacilli in the past two decades. Nevertheless, these organisms still cause a wide spectrum of infection (from benign colonization to disseminated disease), and are associated with substantial morbidity and mortality in patients with cancer, particularly during episodes of neutropenia. The most significant problem to develop in recent years has been the emergence of resistance among most gram-negative pathogens, with some organisms acquiring multiple resistance mechanisms which render them multi-drug-resistant. Exacerbating this problem is the fact that the pipeline for new drug development is relatively dry. This has led to the increased use of combination regimens and the revival of older agents such as colistin. Greater emphasis needs to be placed on antimicrobial stewardship and on strict adherence to infection control policies, in order to reduce the frequency of and limit the spread of these organisms. Bacteroides and other anaerobic Gram-negative bacteria may lead to life threatening infections, presence of refractory hypotension, high grade fever, acute intravascular hemolysis and disseminated coagulation, and early onset of tissue necrosis are the hallmark of this devastating disease. A high level of suspicion and prompt systemic therapy coupled with surgical excision of devitalized tissue when possible may improve outcomes.