Hopkins ABX Guide

Stenotrophomonas Maltophilia Bacterium

What is Stenotrophomonas Maltophilia?

Stenotrophomonas maltophilia is a bacterium of the Stenotrophonomas genus. It is a very rare cause of infection in humans but it is getting more common, especially in immunocompromised individuals in a hospital setting. The rising incidence of Stenotrophomonas maltophilia infection has caused a lot of concern in the medical community because the bacterium is resistant the majority of broad-spectrum antibiotics and as a result, it is very difficult to treat.

The bacterium was first identified in the early 1940s. Originally called Bacterium bookeri, it was initially listed to the Pseudomonas genus and then to the Xanthomonas genus before finally being classified as Stenotrophomonas maltophilia in the early 1990s.

Who is at Risk of Stenotrophomonas Maltophilia Infection?

Stenotrophomonas maltophilia is found in water and aquatic environments. The bacterium isn’t dangerous for healthy individuals and it is very unlikely for a healthy person to get infected with this bacterium species. Despite being relatively rare, however, Stenotrophomonas maltophilia infections are on the rise among hospitalised individuals with a weakened immune system although there were also reports of infections in non-hospitalised population.

Risk factors for Stenotrophomonas maltophilia infection include severe underlying conditions such as chronic lung disease, cancer and most immunocompromising conditions; prolonged hospitalisation; and undergoing treatment involving some sort of prosthetic device such as urinary catheter, breathing tube or central venous catheter. This is because the bacteria are frequently present in hospital liquids/fluids.

Symptoms of Stenotrophomonas Maltophilia Infection

Symptoms of Stenotrophomonas maltophilia infection vary greatly, depending on the body part/organs affected. Infection most often involves the respiratory tract and causes symptoms that are also characteristic for respiratory tract infections that are caused by other pathogens. The bacterium can also cause infection of the urinary tract infection, eyes, bone/join; meningitis (inflammation of the membranes protecting the brain and spinal cord); endocarditis (infection of the heart’s inner lining); and bacteremia (bacteria entering the bloodstream).

Treatment of Stenotrophomonas Maltophilia Infection

As mentioned earlier, Stenotrophomonas maltophilia is very difficult to treat due to its natural resistance to many antibiotics. The most effective treatment involves the removal of prosthetic devices. Antibiotics are used only when removal of prosthesis isn’t possible. Unfortunately, complications and mortality rates are quite high, especially in patients with a compromised immune system.