Klebsiella , enterobacter , and serratia infections

[Oralee]

Klebsiella, Enterobacter, and Serratia are closely related gram-negative bacteria that occasionally infect the urinary tract or respiratory tract of people in hospitals or in long-term care facilities.

These bacteria may infect the urinary or respiratory tract, intravenous catheters used to give drugs or fluids, burns, wounds made during surgery, or the bloodstream.
Identifying the bacteria in a sample taken from blood or from infected tissue confirms the diagnosis.
If the infection is acquired in the community, antibiotics can cure it, but if it is acquired in a health care facility, it is difficult to treat because bacteria tend to be resistant to antibiotics.

(See also Overview of Bacteria.)
Klebsiella, Enterobacter, and Serratia bacteria reside in the intestine of many healthy people and rarely cause infection in them. Infections with these bacteria are often acquired in hospitals and long-term care facilities. They usually occur in people whose resistance to infection is weakened and/or who have a medical device (such as catheters, drains, and airway tubes) in their body.
These bacteria may infect different places in the body:

Urinary or respiratory tract (causing pneumonia, bladder infections, or kidney infections)
Catheters inserted into a vein (intravenous catheter), used to administer drugs or fluids
Burns
Wounds made during surgery
Bloodstream (causing bacteremia or sepsis)

Rarely, Klebsiella bacteria cause pneumonia in people who live outside a health care facility (in the community), usually in alcoholics, older people, people with diabetes, or people with a weakened immune system. Typically, this severe infection causes cough, bringing up a sticky, dark brown or dark red sputum, and collections of pus (abscesses) in the lungs or in the membrane between the lungs and chest wall (empyema).
One species of Klebsiella produces a toxin that can cause inflammation of the colon and bleeding (hemorrhagic colitis) after antibiotics are taken. This disorder is called antibiotic-associated colitis. The antibiotics kill bacteria that normally reside in the intestine. Then Klebsiella bacteria are able to multiply and produce the toxin. However, antibiotic-associated colitis usually results from toxins produced by Clostridium difficile.

[Lizzy Liz]

The gram-negative bacteria Klebsiella, Enterobacter, and Serratia are closely related normal intestinal flora that rarely cause disease in normal hosts. Diagnosis is by culture. Treatment is with antibiotics.
Infections with Klebsiella, Enterobacter, and Serratia are often hospital-acquired and occur mainly in patients with diminished resistance. These three bacteria can cause a wide variety of infections, including bacteremia, surgical site infections, intravascular catheter infections, and respiratory or urinary tract infections that manifest as pneumonia, cystitis, or pyelonephritis and that may progress to lung abscess, empyema, bacteremia, and sepsis, as in the following:

Klebsiella pneumonia, a rare and severe disease with dark brown or red currant–jelly sputum, lung abscess formation, and empyema, is most common among diabetics and alcoholics.
Serratia, particularly S. marcescens, has greater affinity for the urinary tract.
Enterobacter most often cause nosocomial infections but can cause otitis media, cellulitis, and neonatal sepsis.

Diagnosis is by culture of blood and/or other infected tissue. Susceptibility testing is also done.