Bacteria are microscopic organisms that exist in diverse environments, playing various roles from supporting ecosystems to inhabiting the human body. While many bacterial species coexist harmlessly with humans or even offer benefits, others cause infections. These infections can range in severity, leading to serious health complications. Understanding these microorganisms is important for public health.
What is Morganella morganii?
Morganella morganii is a Gram-negative bacterium, a classification based on how its cells react to a specific laboratory staining procedure. It is a member of the Enterobacteriaceae family, a large group of bacteria that commonly reside in the intestines of humans and animals. This rod-shaped bacterium is also found widely in the natural environment, including soil and water.
Although Morganella morganii can exist as a normal part of the gut flora, it is recognized as an opportunistic pathogen. This means it causes disease when a person’s immune system is weakened or when the bacteria gain access to parts of the body where they do not normally reside. While it is a widespread organism, it is not a common cause of infections acquired outside of healthcare settings.
Who is at Risk and How it Spreads
Infections caused by Morganella morganii are more frequently encountered in specific populations and settings. Hospitalized patients face a higher risk, particularly those who have undergone recent surgeries or have pre-existing medical conditions. Individuals with compromised immune systems, such as cancer patients, organ transplant recipients, or those with diabetes, are also more susceptible. Advanced age is another factor that increases vulnerability.
Transmission of Morganella morganii often occurs through contact with contaminated surfaces or medical devices within healthcare environments. Common sources of infection include indwelling medical devices like catheters and ventilators. Wound infections are also frequent, especially in postoperative patients. These bacteria are considered a cause of healthcare-associated (nosocomial) infections due to their prevalence in such settings.
Symptoms and Severe Outcomes
Morganella morganii can cause a range of infections, each presenting with its own symptoms depending on the affected body system. Common infections include urinary tract infections (UTIs), particularly in individuals with catheters, as well as wound infections, pneumonia, and bloodstream infections, known as bacteremia. Symptoms of UTIs include painful urination or frequent urges, while wound infections can lead to redness, swelling, and discharge at the site. Pneumonia caused by this bacterium can manifest with respiratory distress or cough, and bloodstream infections often present with fever and chills.
These infections can progress to severe and potentially life-threatening conditions. Bacteremia, where the bacteria enter the bloodstream, can lead to sepsis. Sepsis is a severe response to infection that can cause widespread inflammation throughout the body. If sepsis is not controlled, it can advance to septic shock, a state characterized by a drop in blood pressure and organ dysfunction. This progression can result in multi-organ failure, where several of the body’s systems begin to shut down, which is how Morganella morganii infections can become fatal. Mortality rates associated with Morganella morganii infections can be high, particularly in patients with underlying health issues or those who do not receive appropriate initial antibiotic therapy.
Diagnosis, Treatment, and Prevention
Diagnosing a Morganella morganii infection typically begins with laboratory testing of samples from the infected site. This often involves culturing blood, urine, or wound fluid to grow and identify the specific bacterium responsible. Once identified, antibiotic susceptibility testing, also known as an antibiogram, is performed to determine which antibiotics will be effective against that particular strain. This step is because Morganella morganii can show varying patterns of antibiotic resistance.
Treatment usually involves the administration of appropriate antibiotics, guided by the susceptibility test results. Commonly used antibiotic classes include carbapenems, third and fourth-generation cephalosporins, fluoroquinolones, and aminoglycosides. For severe infections, supportive care is also provided to manage symptoms and maintain organ function. A challenge in treating Morganella morganii infections is the bacterium’s ability to develop resistance to multiple antibiotics, making treatment more complex. Some strains exhibit intrinsic resistance to certain beta-lactam antibiotics and can acquire additional resistance genes.
Preventive measures minimize the risk of acquiring and spreading Morganella morganii. Proper hand hygiene practices and strict infection control protocols in healthcare settings limit transmission. Careful attention to wound care and judicious use of medical devices, such as catheters, can also help reduce the chances of infection. These steps control the spread of this opportunistic pathogen.