Corynebacterium xerosis

Corynebacterium xerosis

Corynebacterium xerosis Gram stain

Corynebacterium xerosis is a species of bacteria belonging to the genus Corynebacterium. It is a Gram-positive, non-motile, non-spore-forming rod that is commonly found in the human microbiota of the skin and mucous membranes. C. xerosis is part of the normal flora but can act as an opportunistic pathogen, particularly in immunocompromised individuals.

Morphology and Identification

Corynebacterium xerosis is characterized by its rod-shaped morphology, which can appear as club-shaped or irregularly shaped under the microscope. The cells are arranged in palisades or in a "V" formation, a characteristic feature of the genus Corynebacterium. When stained using the Gram stain method, C. xerosis appears as Gram-positive due to its thick peptidoglycan layer.

On blood agar, C. xerosis forms small, white to cream-colored colonies. The colonies are typically dry and may exhibit a slight yellowish tint. The colonial morphology can be used as a preliminary identification tool in the laboratory.

Corynebacterium xerosis colonial morphology on blood agar

Pathogenicity

While Corynebacterium xerosis is generally considered non-pathogenic, it can cause infections in certain circumstances. It has been isolated from cases of bacteremia, endocarditis, and wound infections, particularly in patients with compromised immune systems. The organism's ability to form biofilms on medical devices can contribute to its pathogenic potential.

Clinical Significance

In clinical settings, Corynebacterium xerosis is often regarded as a contaminant when isolated from cultures. However, its presence should not be dismissed in patients with underlying health conditions or those with indwelling medical devices. Accurate identification and susceptibility testing are crucial for appropriate management of infections caused by this organism.

Laboratory Diagnosis

The diagnosis of Corynebacterium xerosis infections involves the isolation and identification of the organism from clinical specimens. Standard microbiological techniques, including culture on selective media and biochemical tests, are employed. Molecular methods, such as polymerase chain reaction (PCR), can provide rapid and specific identification.

Treatment

Infections caused by Corynebacterium xerosis are typically treated with antibiotics. The choice of antibiotic depends on the susceptibility profile of the isolate. Commonly used antibiotics include penicillin, erythromycin, and vancomycin. It is important to perform susceptibility testing due to the potential for antibiotic resistance.

Prevention and Control

Preventive measures for infections caused by Corynebacterium xerosis include maintaining good hygiene practices, especially in healthcare settings. Proper sterilization of medical equipment and careful monitoring of patients with indwelling devices can reduce the risk of infection.

Related Pages

• Corynebacterium diphtheriae
• Corynebacterium jeikeium
• Gram-positive bacteria
• Opportunistic infection