What Is Acinetobacter Baumannii?

The Acinetobacter superbug can cause diseases such as pneumonia and meningitis.

Acinetobacter baumannii is a bacterium that can cause a range of diseases.

It typically infects people inside a healthcare facility — doctors refer to these as "nosocomial" infections.

There are many different species of Acinetobacter that can cause disease, but A. baumannii accounts for about 80 percent of reported Acinetobacter infections in the United States, according to the Centers for Disease Control and Prevention (CDC).

Acinetobacter Risks

Healthy people have a very low risk of getting an A. baumannii infection, according to the CDC.

The following factors increase the risk of infection:

• Having a weakened immune system
• Chronic lung disease
• Diabetes
• Lengthy hospital stays
• Illnesses that require the use of a hospital ventilator
• Having an open wound treated in the hospital
• Treatments requiring invasive devices like urinary catheters

Acinetobacter bacteria are not airborne, but can be spread through direct contact with surfaces, objects, or the skin of people that are contaminated with A. baumannii.

Acinetobacter Symptoms

Acinetobacter is an opportunistic bacterium that causes a variety of different diseases with different symptoms.

Types of possible A. baumannii infections include:

• Pneumonia
• Bloodstream infections (bacteremia and sepsis)
• Meningitis (an infection or inflammation of the meninges, the membranes covering the brain and spinal cord)
• Wound and surgical site infections, including the "flesh-eating" bacterium necrotizing fasciitis
• Urinary tract infections (UTI)

Symptoms of A. baumannii infections are often clinically indistinguishable from those of infections caused by other opportunistic bacteria, such as Klebsiella pneumoniae and Streptococcus pneumoniae.

Bloodstream infections often initially cause symptoms like fever and chills, rash, and confusion or other altered mental states, and are often associated with an elevated lactic acid level that’s found with severe sepsis.

UTIs typically cause various urinary symptoms, including pain or burning sensations while urinating, foul-smelling urine that may be cloudy or bloody, and a strong urge to urinate frequently.

Meningitis may cause a number of flu-like symptoms, including fever, headache, confusion, sensitivity to bright light, and nausea (with or without vomiting).

Pneumonia may cause a range of symptoms, including but not limited to:

• Chills
• Fever
• Headache
• Breathing problems
• Muscle pain and chest pain
• Cough, sometimes with yellow, green, or bloody mucus

In some cases, A. baumannii may colonize a site, such as an open wound or a tracheostomy site, without causing any infection or symptoms.

Acinetobacter Treatment and 'Superbug' Antibiotic Resistance

The CDC considers Acinetobacter, including A. baumannii, a serious public health threat because it's often resistant to multiple antibiotics.

In fact, 63 percent of Acinetobacter strains are multidrug-resistant, the CDC notes.

Before the 1970s, A. baumannii infections could be treated with a range of different antibiotics, such as aminoglycosides, β-lactams, and tetracyclines, according to a report in the journal Clinical Microbiology Reviews.

Today, however, some strains of A. baumannii are resistant to most antibiotics, including first-line antibiotics and carbapenems, which are often used only as a last resort.

Treating an A. baumannii infection generally requires drug susceptibility tests, which check for antibiotics that are still effective against the particular strain of bacteria.

In some cases, sulbactam and polymyxin antimicrobial drugs still work against A. baumannii when other antibiotics fail.