Enterobacter Aerogenes Characteristics

As part of the Enterobacteriaceae family, Enterobacter aerogenes is related to E. coli and salmonella. In terms of size, E. aerogenes is smaller than many of its microbial cousins, but its occurrence in hospitals and resistance to antibiotics have made it of particular importance. As E. aerogenes continues to evolve new strains, it will continue to pose challenges to the biomedical community.

Bacteriology

• E. aerogenes is a rod-shaped bacteria, or a "bacillus" in scientific lingo. As a facultative anaerobe, it thrives in environments with little or no oxygen, such as soil, sewage and feces.

  In a laboratory, E. aerogenes grows well in MacCongey agar, which contains, dyes, salts and milk sugar. Its optimal growing temperature ranges from 30 to 37 degrees Celsius.

Illnesses

• E. aerogenes causes a wide range of illnesses, depending on which part of the body it invades. Common illnesses include bacteremia, osteomyelitis, pneumonia and septicemia. However, E. aerogenes also causes infections in the gastrointestinal tract, the respiratory tract, the urinary tract and skin.

Risk Factors

• E. aerogenes is an opportunistic pathogen. This means that it infects a host that has already been weakened. E. aerogenes is also a nosocomial bacteria, which means that it commonly resides in hospitals. Consequently, its risk factors include hospital stays that last 2 weeks or longer, invasive surgery, intensive care visits and use of antibiotics.

Predilections

• Like other Enterobacter bacteria, E. aerogenes has no predilection for race. However, it does occur more frequently among newborns, toddlers and the elderly, particularly among males.

Treament

• E. aerogenes is resistant to most antibiotics, including chloramphenicol, quinolones and tetracycline. As a result, the use of "old" drugs---that is, drugs that were commonly prescribed in past decades---is growing in popularity. Another popular treatment is using a combination of drugs such as imipenem and gentamicin.