Antibiotic resistance patterns of coagulase-negative staphylococcus strains isolated from blood cultures of septicemic patients in Turkey

Abstract

The aim of this study is to determine antibiotic resistance patterns and slime production characteristics of coagulase-negative Staphylococci (CoNS) caused nosocomial bacteremia. A total of 200 CoNS strains were isolated from blood samples of patients with true bacteremia who were hospitalized in intensive care units and in other departments of Istanbul University Cerrahpasa Medical Hospital between 1999 and 2006. Among 200 CoNS isolates, Staphylococcus epidermidis was the most prevalent species (87) followed by Staphylococcus haemolyticus (23), Staphylococcus hominis (19), Staphylococcus lugdunensis (18), Staphylococcus capitis (15), Staphylococcus xylosus (10), Staphylococcus warneri (8), Staphylococcus saprophyticus (5), Staphylococcus lentus (5), Staphylococcus simulans (4), Staphylococcus chromogenes (3), Staphylococcus cohnii (1), Staphylococcus schleiferi (1), and Staphylococcus auricularis (1). Resistance to methicillin was detected in 67.5% of CoNS isolates. Methicillin-resistant CoNS strains were determined to be more resistant to antibiotics than methicillin-susceptible CoNS strains. Resistance rates of methicillin-resistant and methicillin-susceptible CoNS strains to the antibacterial agents, respectively, were as follows: gentamicin 90% and 17%, erythromycin 80% and 37%, clindamycin 72% and 18%, trimethoprim-sulfamethoxazole 68% and 38%, ciprofloxacin 67% and 23%, tetracycline 60% and 45%, chloramphenicol 56% and 13% and fusidic acid 25% and 15%. None of the strains were resistant to vancomycin and teicoplanin. Slime production was detected in 86 of 200 CoNS strains. Resistance to methicillin was found in 81% of slime-positive and in 57% of slime-negative strains. Our results indicated that there is a high level of resistance to widely used agents in causative methicillin-resistant CoNS strains. However fusidic acid has the smallest resistance ratio, with the exception of glycopeptides. Additionally, most S. epidermidis strains were slime-positive, with statistically significant (p<0.001) association between methicillin resistance and slime production.

Core genome conservation of Staphylococcus haemolyticus limits sequence based population structure analysis

“…patients with haematological disease and immature infants (Nouri et al, 2008). The ability to produce biofilm and the notoriously multi-resistance to antimicrobial agents, including glycopeptides, favours S. haemolyticus as an emerging cause of nosocomial infections (de Allori et al, 2006;Falcone et al, 2006;Fredheim et al, 2009;Froggatt et al, 1989;Hiramatsu, 1998;Hope et al, 2008;Koksal et al, 2009;Schwalbe et al, 1987).…”

“…In this report we describe the development of a MLST and a MLVF scheme, and the observation of a conserved core genome in S. haemolyticus (Koksal et al, 2009). …”

Impact of empiric antibiotic regimen on bowel colonization in neonates with suspected early onset sepsis

“…The different colonization pattern may still have clinical relevance as mucosal colonisation is a potential source of CoNS in invasive infections [14]. Differences in the pathogenicity of CoNS species have been demonstrated with 71% of S. epidermidis but only 35% of S. haemolyticus and 26% of S. hominis strains being capable of slime production, the latter being associated with invasive disease [39][40][41]. The relevance of differences in gut colonization observed in this study is further supported by the clinical findings showing a trend towards greater prevalence of LOS caused by S. epidermidis in the penicillin compared with the ampicillin arm (7.6 vs 2.7 per 100 patient days, respectively).…”

Methicillin-resistant Staphylococcus spp. isolated from curd cheese “requeijão” and “especialidade láctea type requeijão” sold in Brazil

“…Consequently, Staphylococcus spp. antimicrobial resistance is a concern for public health (KOKSAL et al, 2009).…”