Corynebacterium striatum peritoneal dialysis catheter exit site infection

Regarded as normal flora of the human skin and mucus membranes, non-diphtheria corynebacteria are frequently dismissed as contaminants or harmless colonizers. Recently, the pathogenic potential of C. striatum has been realized in immunocompromised patients with indwelling medical devices and previous antibiotic exposure.

We report here the diagnosis, treatment and clinical outcome of a peritoneal dialysis patient with a C. striatum infection of the catheter exit site. The aim is to present important features to assist in identifying clinically significant infections and provide guidelines for treatment.

An immunocompromised patient with previous antimicrobial exposure developed an acute dialysis catheter exit site infection. C. striatum was isolated in pure growth. After initial treatment failure with oral antibiotics and intensified wound care, a satisfactory outcome was ultimately achieved without relapse or loss of the catheter with a 1-month course of vancomycin, 1 g intravenously, administered at 5-day intervals.

The virulent capacity of Corynebacterium species should not be underestimated, particularly in high-risk patients. The presence of clinical signs of infection with isolation of the organism in pure culture and the presence of Gram-positive rods on direct Gram stain, especially in association with a leukocyte reaction, supports a cause and effect relationship. Because corynebacteria may be multiresistant, susceptibility testing should be performed on clinically significant isolates. Initial antibiotic selection is influenced by the severity of the infection, however, current experience favors vancomycin in significant infections.