Pseudomonas is a genus of bacteria containing a variety of organisms that pose a significant risk to health. Commonly, Pseudomonas infections occur in people who have underlying conditions, which can make them more vulnerable to disease that people in good health. Characteristics of the genus include resistance to cleaning agents, and an ability to mutate rapidly to become immune to antibiotics. For these reasons, Pseudomonas resistance is of major concern to public health authorities, especially in locations like hospitals, where the bacteria tend to colonize and become difficult to dislodge.
A defining characteristic of the Pseudomonas genus is that the bacteria are commonly able to form structures called biofilms. These form over a wet or damp surface, and together resist removal with scrubbing or with cleaning products. Pseudomonas bacteria are very common in nature, and are present in the earth and in water sources, where this biofilm ability presumably originated as a beneficial mechanism. When the bacteria get into hospitals, or into medical equipment, however, the biofilms they produce can be very hard to eradicate.
Together with this ability to colonize an area, Pseudomonas species can also infect humans. A healthy person normally has an immune system that is strong enough to repel Pseudomonas bacteria attempting to invade, but a person who is already dealing with disease may have an impaired immune system. Bacteria within this genus are a common source of infections that are acquired in hospitals, which is why public health authorities may focus a lot of effort on controlling the problem. In addition, they can cause a variety of different illnesses, not limited to one type of infection.
On top of these characteristics of Pseudomonas species, the bacteria are also able to mutate rapidly enough to dodge a lot of antibiotic treatments. This is termed Pseudomonas resistance, and various different means of it can develop. Typically, an antibiotic targets a specific feature of a bacterium, and mutations in this feature can make an individual bacterial cell. From an initial infection of millions of bacteria, even if the antibiotic kills off the rest, the mutated cells can survive and grow back into millions of cells.
Often, an antibiotic needs to get inside the cell to work, and Pseudomonas resistance mechanisms to either prevent the drug from entering, or push it back out once it gets in, can help confer resistance to a specific drug. Another possible form of resistance is that the bacterial cell produces enzymes that actively break down the antibiotic to make it harmless. As bacteria can share genes for resistance, as well as develop resistance spontaneously, controlling Pseudomonas resistance is important to be able to cure people who suffer from these type of infections.
Commonly, antibiotic resistance is so widespread in the environmental or hospital-based population of bacteria that two or more antibiotics need to be used. Apart from increasing the risk of side effects on the patient, this approach is more expensive than using only one drug. Treatment for resistant bacteria can also take longer, and require drugs that are not commonly used due to a high risk of side effects. Finally, new antibiotics always need to be in production, to keep up with the development of resistance in the bacteria against the existing products.