skin independently. As a result, Staphylococcus organisms usually cause nosocomial, or hospital-acquired, infections, as patients in the hospital are more susceptible to opportunistic infections. Once in the blood, Staphylococcus aureus can move to the joints, heart, and bones, and cause septic arthritis, endocarditis, and osteomyelitis, respectively. In addition, bacteremia, or bacterial infection of the blood, can lead to septic shock. Staphylococcus aureus can cause scalded skin syndrome, toxic shock syndrome, and food poisoning. Organisms of the Staphylococcus genus contain Protein A which binds to antibodies and prevents them from attacking, can produce superantigen antitoxins that confuse host defenses, and have antibiotic resistance to penicillin in addition to many other antibiotics. Thus, although antibiotics are effective, they are limited, so Staphylococcus aureus can potentially be dangerous for the host.
Alcaligenes faecalis is a Gram negative, rod-shaped bacteria. Organisms of the genus Alcaligenes can be found everywhere, including marine waters, freshwaters, sewage, soil, feces of healthy individuals, and hospital environments. They are nonfermentative, and therefore are not capable of using glucose, lactose, sucrose, and most other carbohydrates. Alcaligenes faecalis bacteria are motile, oxidase positive, citrate positive, gelatinase negative, urease negative, hydrogen sulfide negative, indole negative, obligate aerobes.
Alcaligenes faecalis is clinically relevant because although it can be found naturally inhabiting the intestines of humans, it is an opportunistic pathogen and thus is commonly found affecting people with suppressed immune systems. It can cause nosocomial infections, because patients in the hospital have weakened immune systems due to surgeries or illnesses, and cystic fibrosis patients are at a higher risk of being infected. It can cause infections such as peritonitis, meningitis, appendicitis, chronic otitis, and bacteremia, or infection of the bloodstream. Usually, when treating diseases caused by Alcaligenes faecalis, the outcome is positive. However, treatment against these diseases can potentially be very difficult due to Alcaligenes faecalis’ resistance to many types of regularly used antibiotics. In the case of A. faecalis diseases, the antibiotics carbapenems, antipseudomonal penicillins, and trimethoprim, are considered relatively more effective in treating the disease. Evidently, Alcaligenes faecalis is a significant bacterium because it can be found in water or aqueous environments and can cause opportunistic infections that may be difficult to treat using antibiotics.
