What are Diphtheroids?
Diphtheroids are a group of bacteria that are part of the normal flora of the human body, particularly on the skin and mucous membranes. They are
Corynebacterium species, closely related to the bacterium that causes diphtheria but are typically non-pathogenic. While they are usually harmless, under certain conditions, they can become opportunistic pathogens and cause infections.
How do Diphtheroids Differ from Diphtheria?
The primary pathogen responsible for diphtheria is
Corynebacterium diphtheriae, which produces a potent toxin leading to the disease's characteristic symptoms. In contrast, diphtheroids like
Corynebacterium striatum or
Corynebacterium amycolatum do not produce this toxin and are generally benign. However, they can occasionally cause disease, particularly in immunocompromised individuals or those with invasive devices such as catheters.
Are Diphtheroids Clinically Significant?
While often dismissed as contaminants in clinical samples, diphtheroids can be clinically significant, especially in certain contexts. For instance, in patients with weakened immune systems or those undergoing major surgeries, diphtheroids can cause infections such as
endocarditis,
bacteremia, or
wound infections. Their clinical significance is particularly noted when they are isolated in pure culture from normally sterile sites.
How are Diphtheroid Infections Diagnosed?
Diagnosis of diphtheroid infections involves
culturing the organism from clinical specimens and correlating it with clinical symptoms. It is essential to distinguish between contamination and true infection, which requires careful clinical judgment and laboratory support. Advanced molecular techniques can further characterize the species and determine their potential pathogenicity.
What is the Treatment for Diphtheroid Infections?
Treatment of diphtheroid infections often involves the use of
antibiotics, tailored based on susceptibility testing. Commonly used antibiotics include
vancomycin,
linezolid, and
daptomycin. In addition to antibiotic therapy, addressing any underlying conditions or removing infected devices is crucial for successful treatment.
How Can Diphtheroid Infections be Prevented?
Prevention of diphtheroid infections involves proper
hygiene and
infection control practices, especially in healthcare settings. This includes regular handwashing, proper sterilization of medical equipment, and careful management of invasive devices. For individuals with compromised immune systems, additional precautions may be necessary to prevent potential opportunistic infections.
Conclusion
Diphtheroids are generally harmless inhabitants of the human body but can become problematic under specific conditions, particularly in vulnerable populations. Understanding their role in infectious diseases is crucial for clinicians to differentiate between contamination and true infection, ensuring appropriate management and treatment. Continuous research and awareness are essential to effectively address the challenges posed by these opportunistic pathogens.
