Bloodstream Infection caused by Corynebacterium striatum in COVID-19 patient

Abstract

Objectives: Recent research recognized coryneform bacteria as emerging opportunistic pathogens. Corynebacterium striatum appears as a significant pathogen in immunocompromised and immunocompetent patients. Methods: In this paper, we report a case of an adult COVID-19 patient with C. striatum bloodstream infection. In addition, we reviewed clinical cases of bloodstream infection caused by Corynebacterium spp, mainly C. striatum. Results: We present a 43-year-old patient hospitalized due to bilateral pneumonia caused by a SARS-CoV-2 infection. During hospitalization, the patient was connected to a veno-venous extracorporeal membrane oxygenation (ECMO) circuit. C. striatum was isolated in seven sets of blood cultures sampled over seven consecutive days. Based on identification done by MALDI- ToF, empirical therapy with vancomycin was initiated. Identification was confirmed by 16S ribosomal RNA gene sequencing. Although central venous catheter was replaced, C. striatum was persistently isolated in blood cultures in the following days. Although replacement of the ECMO cannula would be recommended, the procedure was not performed due to the severe patient's condition. Fosfomycin was added to vancomycin as salvage therapy in order to reorganize the structure of the biofilm and enable better penetration and efficacy of vancomycin which resulted in sterile blood cultures in the following days. Conclusion: During the last decades, there have been many examples of bloodstream infections caused by skin contaminants. Although the central venous catheter is most commonly described as a route of entry of the skin microbiota in the bloodstream, other catheters such as pleural catheter and ECMO system, should not be neglected. It is well known that bacterial cells often form a biofilm on the surface of different medical devices such as central venous catheters, endoscopes, and urinary catheters. Fosfomycin has the potential to penetrate the biofilm, transform the biofilm structure and potentially increase the concentration of other antimicrobial agents in the biofilm.