Trueperella bernardiae is a bacterium commonly found on human skin, in the oropharynx, and within the gastrointestinal and urogenital tracts. This gram-positive coccobacillus is non-spore-forming and non-motile, often appearing singly, in clusters, or in pairs. While usually harmless as part of the normal flora, Trueperella bernardiae can become an opportunistic pathogen, causing infections under specific conditions. Its identification has become more frequent with advanced diagnostic techniques.
Infections Caused by Trueperella Bernardiae
When Trueperella bernardiae becomes pathogenic, it can lead to various clinical manifestations, often in patients with underlying health issues. Skin and soft tissue infections are frequently reported, including abscesses and cellulitis. Surgical wound infections are also a known complication.
The bacterium can also cause bloodstream infections (bacteremia), which may lead to severe symptoms such as fever and chills. Septic arthritis, an infection of the joints, can manifest with joint pain, swelling, and reduced mobility. Urinary tract infections (UTIs) have been documented, potentially causing symptoms like fever, and in severe cases, progressing to sepsis.
Other reported infections include prosthetic joint infections, osteomyelitis, and brain abscesses. Trueperella bernardiae is often found in polymicrobial infections, complicating the clinical picture. The true incidence of these infections is not fully known, partly because this bacterium was previously often considered a contaminant in clinical samples.
Risk Factors for Infection
Infections caused by Trueperella bernardiae arise when an individual’s natural defenses are compromised, allowing this opportunistic bacterium to cause disease. A weakened immune system significantly increases susceptibility, as seen in patients with conditions like HIV/AIDS, cancer, or those receiving immunosuppressive drugs. These individuals have a reduced ability to fight off infections, making them vulnerable to pathogens that are usually harmless.
Chronic diseases also play a role, with diabetes mellitus being a common underlying condition that predisposes individuals to Trueperella bernardiae infections, particularly in cases of diabetic foot ulcers. Recent surgical procedures create an entry point for bacteria, making surgical wounds a common site for infection. The presence of foreign medical devices, such as catheters or prosthetic joints, also increases the risk.
Advanced age is another contributing factor, as older individuals may have compromised skin integrity and overall health, making them more prone to infections. These infections are generally not transmitted from person to person; instead, they originate from the individual’s own bacterial flora when a vulnerability allows the bacteria to proliferate and cause disease.
Diagnosis and Treatment
Diagnosing an infection caused by Trueperella bernardiae involves identifying the bacterium from a clinical sample taken from the infected site. Doctors collect samples such as a wound swab, blood, or urine, which are then sent to a laboratory for bacterial culture. The bacteria are readily cultured, with growth often observed within 2–5 days.
Initial identification can be challenging with conventional laboratory methods, as Trueperella bernardiae may be mistaken for other bacteria. Modern techniques like Matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry have significantly improved identification. Once identified, antibiotic susceptibility testing is performed to determine which antibiotics will be most effective against the specific strain.
Trueperella bernardiae is often susceptible to common antibiotics, including beta-lactams such as penicillin, amoxicillin/clavulanate, and cephalosporins, as well as vancomycin and clindamycin. Some strains may show resistance to certain drugs like ciprofloxacin or erythromycin, highlighting the importance of susceptibility testing to guide treatment. In addition to antibiotic therapy, procedural interventions are frequently necessary, particularly for localized infections like abscesses. Surgical drainage of abscesses or debridement of infected tissue is often performed to remove the source of infection and facilitate healing, working in conjunction with antibiotics.