Nondiphtherial Corynebacterium species isolated from clinical specimens of patients in a university hospital, Rio de Janeiro, Brazil

Abstract

Over a five-year period, 163 strains of Corynebacterium sp. were recovered from different clinical specimens of patients from a Brazilian University hospital. Genitourinary tract and intravenous sites specimens were the most frequent sources of corynebacteria (46.62%). Corynebacterium amycolatum (29.55%), Corynebacterium minutissimum (20.45%) and Corynebacterium pseudodiphtheriticum (13.63%) were the predominant species found in genitourinary tract. C. minutissimum (24.14%) and Corynebacterium propinquum (17.24%) in surgical and/or other skin wounds and abscesses; Corynebacterium xerosis (25%), C. amycolatum (21.87%) and C. pseudodiphtheriticum (18.75%) in intravenous sites; C. pseudodiphtheriticum (33.33%) and C. propinquum (33.33%) in lower respiratory tract. Microorganisms were all susceptible to vancomycin and most of the species was predominantly resistant to β-lactams. Antimicrobial susceptibility patterns of corynebacteria were not predictable. Multiple antibiotic resistance observed in C. jeikeium was also found among C. xerosis, C. minutissimum, C. afermentans, C. propinquum, C. amycolatum and C. pseudodiphtheriticum strains. Data suggest awareness of clinicians and microbiologists to nosocomial infections especially due to antimicrobial multiresistant strains of Corynebacterium sp.

Clonal multidrug-resistant Corynebacterium striatum within a nosocomial environment, Rio de Janeiro, Brazil

“…In contrast to previous data observed by our research group (Camello et al 2003), an unusual clustering of 14 patients in our teaching hospital within a period of nine months produced a sentinel signal that justified the study of a possible outbreak. Therefore, the microbiologic characteristics, resistance profiles and similarities among the genomes of 15 C. striatum strains isolated from these patients were investigated.…”

“…Blood specimens were inoculated in Bactec Plus anaerobic⁄aerobic vials and processed in a Bactec 9240 continuous-monitoring system (Becton-Dickinson Microbiology System, Cockeysville, MD, USA). Other clinical specimens were inoculated onto a Columbia agar base with the addition of 5% sheep's blood and incubated at 37ºC in a 3-5% CO 2 atmosphere and monitored for 72 h (Camello et al 2003). Positive bacterial cultures for irregular Gram-positive rods were preliminarily characterised by colonial morphology, pigmentation, haemolysis, DNase activity and CAMP reaction with Staphylococcus aureus (Camello et al 2003, Funke & Bernard 2007, Pimenta et al 2008.…”

“…Other clinical specimens were inoculated onto a Columbia agar base with the addition of 5% sheep's blood and incubated at 37ºC in a 3-5% CO 2 atmosphere and monitored for 72 h (Camello et al 2003). Positive bacterial cultures for irregular Gram-positive rods were preliminarily characterised by colonial morphology, pigmentation, haemolysis, DNase activity and CAMP reaction with Staphylococcus aureus (Camello et al 2003, Funke & Bernard 2007, Pimenta et al 2008. Phenotypic characterisation was also performed using the semi-automated API Coryne System 3.0 (bioMérieux) with the API web decoding system (apiweb.biomerieux.com) (Almuzara et al 2006, Funke & Bernard 2007, Campanile et al 2009).…”

“…For the other antimicrobial agents, we used the breakpoints for other microorganisms, but not Haemophilus spp or Neisseria gonorrhoeae, which had been validated by previous studies. Intermediate results were considered resistant (Camello et al 2003). The antibiotics (Oxoid SA, Spain) tested included penicillin (10 U), ampicillin (30 µg), methicillin (5 µg Gene amplification and sequencing -C. striatum identification was confirmed by 16S rRNA and rpoB gene sequencing.…”

“…In South America, only reports from Brazil indicate the sporadic isolation of C. striatum from representative clinical sites of hospitalised patients with signs and symptoms of infection (Camello et al 2003, Superti et al 2009). In contrast to previous data observed by our research group (Camello et al 2003), an unusual clustering of 14 patients in our teaching hospital within a period of nine months produced a sentinel signal that justified the study of a possible outbreak.…”