In-vitro antibiotic resistance profile of Corynebacterium striatum strains isolated from clinical samples

Abstract

Corynebacterium striatum is a normal inhabitant of human skin and mucous membranes. However, it has recently been reported as the cause of invasive infections and outbreaks. In addition, multidrug resistance of the bacterium is a significant concern. In this study, we aimed to determine the antimicrobial resistance of C.striatum strains to contribute to empirical antibiotic usage protocols. A total of 235 C.striatum strains isolated from inpatients between January 2017-December 2018 were investigated retrospectively. The strains were identified using the Phoenix 100 (Becton Dickinson, MD, USA) fully automated system and antibiotic susceptibilities of isolates was determined by using Kirby-Bauer disc diffusion method. Antimicrobial susceptibilities of strains were interpreted according to The European Committee on Antimicrobial Susceptibility Testing standards. Of the 235 patients in whom strains were isolated, 114 were female and 121 were male. The mean age was 72 years and 70 % (n=165) of the patients were in the geriatric age group (65 years, and older). C.striatum strains were isolated from intensive care units at a rate of 71 %. The strains were mostly isolated from the surgical intensive care unit (27 %) internal intensive care unit (26 %) and palliative care unit (14 %). C.striatum strains obtained from the respiratory tract samples (41 %), blood (32 %), and wound samples (27 %). All strains were susceptible to vancomycin and linezolid. However, the resistance rate to gentamicin was 37 % and for erythromycin, it was 55 %. The resistance rates to clindamycin, tetracycline, ciprofloxacin, and cefotaxime were extremely high at 87 %, 93 %, 94 %, and 96 %, respectively. According to our study results, treatment options for C.striatum infections are limited. Therefore vancomycin or linezolid can be preferred in empirical antibiotic treatment.

Antimicrobial Resistance and Molecular Epidemiology of Corynebacterium striatum Isolated in a Tertiary Hospital in Turkey

“…It has also been reported that the tetA and tetB genes play a role in the tetracycline resistance of C. striatum strains and that the mechanism of resistance involves an active efflux pump [26,31]. Many recent studies have not reported resistance to vancomycin and linezolid [16,[23][24][25]. Similarly, in our study, all strains were susceptible to vancomycin and linezolid.…”

“…In earlier reports, C. striatum strains were susceptible to many antibiotics [21,22]. However, they have been reported to be multidrug-resistant in recent studies [16,[23][24][25]. In the present study, all the C. striatum strains were resistant to penicillin, cefotaxime, and ciprofloxacin.…”