Non-Fermenters - Emerging Health Care Pathogens

Aerobic nonfermenting gram-negative bacilli (nonfermenters) are a heterogeneous group of organisms that are either incapable of utilizing carbohydrates as a source of energy or degrade them via oxidative rather than fermentative pathway. These organisms are common inhabitants of soil and water. Nonfermenters can cause a vast variety of infections and account for approximately 15%of all Gram negative bacilli cultured from clinical specimens. Their infection are endogenous or exogenous origin, depending on several factor such as use of immunosuppressant substance, abusive use of wide spectrum antimicrobial agents, prolong surgical procedure and inadequate instrumentation. Pseudomonas cause endocarditis, osteomyelitis, urinary tract infections, gastrointestinal infections, meningitis, and, commonly septicaemia. Acinetobacter has emerged as an important nosocomial organism causing infectious outbreaks in critically ill patients leading to high mortality and morbidity. Burkholderia cepacia shows fast growth on immune-depleted patients - like cystic fibrosis patients (CFPs). Sphingomonas paucimobilis can produce biofilms or attach to preexisting biofilms, where they become integrated and survive for days. Most infections caused by nonfermenters have been nosocomial, often related to contamination of hospital equipment or fluids and have occurred in immunocompromised hosts. Non-fermenting Gram-negative bacilli are innately resistant to many antibiotics and are known to produced extrended spectrum β-lactmases and metallo β-lactmases. This review article highlights the different clinical conditions caused by the nonfermenters.