Ali Asan

Systemic and local antibiotic prophylaxis in the prevention of Staphylococcus epidermidis graft infection

BackgroundThe aim of the study was to investigate the in vivo efficacy of local and systemic antibiotic prophylaxis in the prevention of Staphylococcus (S.) epidermidis graft infection in a rat model and to evaluate the bacterial adherence to frequently used prosthetic graft materials.MethodsGraft infections were established in the subcutaneous tissue of 120 male Wistar rats by implantation of Dacron/ePTFE grafts followed by topical inoculation with 2 × 107 CFUs of clinical isolate of methicillin-resistant S. epidermidis. Each of the graft series included a control group, one contaminated group that did not receive any antibiotic prophylaxis, two contaminated groups that received systemic prophylaxis with teicoplanin or levofloxacin and two contaminated groups that received teicoplanin-soaked or levofloxacin-soaked grafts. The grafts were removed 7 days after implantation and evaluated by quantitative culture.ResultsThere was significant bacterial growth inhibition in the groups given systemic or local prophylaxis (P < 0.05). Methicillin-resistant S. epidermidis had greater affinity to Dacron graft when compared with ePTFE graft in the untreated contaminated groups (P < 0.05).ConclusionThe study demonstrated that the usage of systemic or local prophylaxis and preference of ePTFE graft can be useful in reducing the risk of vascular graft infections caused by staphylococcal strains with high levels of resistance.

Evaluation of Device Associated Infection Rates in Intensive Care Units of Pamukkale University Hospital

Intensive care units (ICUs) are unfortunately the epicenters of nosocomial infections. The aim of the study was to investigate device associated infection rates in a small Turkish hospital. Device utilization ratios and device associated infection rates were calculated according to definitions of the Centers for Disease Control (CDC). During a period of 24 months 1,387 patients were surveyed in our ICUs. A total of 287 device associated infections were detected. In our study ventilator associated pneumonia was the most frequent nosocomial infection with a rate of 59.7 per 1,000 ventilator days. The most frequent pathogen of device associated infection was Candida spp. High rates of device associated infections in a small Turkish hospital clearly indicate the urgent need of the implementation of infection control guidelines.

Linezolid compared with vancomycin for the prevention of methicillin-resistant Staphylococcus aureus or Staphylococcus epidermidis vascular graft infection in rats: A randomized, controlled, experimental study

BACKGROUND Graft infections are severe complications of vascular surgery that may result in amputation or mortality. Staphylococci are the most frequent cause of vascular graft infections. OBJECTIVE In this study we assessed the prophylactic efficacy of linezolid in comparison with vancomycin in preventing prosthetic vascular graft infection due to methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-resistant Staphylococcus epidermidis (MRSE). METHODS This randomized, controlled, experimental study using healthy adult (aged >5 months) male Wistar rats was conducted in the research laboratory of the Pamukkale University, Denizli, Turkey. The study consisted of an uncontaminated control group and 3 groups for both staphylococcal strains: a contaminated group that did not receive any antibiotic prophylaxis; a contaminated group that received preoperative intraperitoneal (IP) prophylaxis with vancomycin; and a contaminated group that received preoperative IP prophylaxis with linezolid. All rats received a vascular Dacron graft placed inside a subcutaneous pocket created on the right side of the median line. Sterile saline solution (1 mL), to which MRSA or MRSE at a concentration of 2 × 10(7) colony-forming units per milliliter had been added, was inoculated onto the graft surface using a tuberculin syringe to fill the pocket. The grafts were explanted 7 days after implantation and assessed by quantitative culture. RESULTS Seventy rats (mean [SD]weight, 323.7 [17.9]g; mean [SD]age, 5.98 [0.64] months) were evenly divided between the 7 groups. Statistical analysis of the quantitative graft culture suggested that both vancomycin and linezolid were effective in significantly inhibiting bacterial growth when compared with the untreated contaminated groups (all, P < 0.001). However, a statistically significant difference was not observed between the bacteria count in the vancomycin and linezolid prophylaxis groups. When a comparison was made between the bacterial growth in the contaminated control groups, MRSA had significantly greater affinity to the Dacron prostheses than MRSE (all, P < 0.001). CONCLUSION Our study found that linezolid was as effective as vancomycin in suppressing colony counts in MRSA- or MRSE-infected vascular Dacron grafts in rats.

Factors affecting responsiveness to hepatitis B immunization in dialysis patients

BackgroundHepatitis B virus (HBV) and hepatitis C virus (HCV) infections are widespread health problems all over the world and have high morbidity and mortality. Hemodialysis patients are more frequently exposed to these viruses as they have poor immune system and frequently undergo parenteral interventions. The vaccination against HBV prevents infection and it has been recommended for the prevention of HBV infection in all susceptible dialysis patients. This study aimed to determine the seroprevalence of HBV and HCV infections and analyzed the factors affecting inadequate response to HBV vaccine in dialysis patients.MethodsThe data for 584 dialysis patients that were followed up at seven dialysis centers were analyzed. The patients received four doses of 40 μg recombinant hepatitis B vaccine at 0, 1, 2, and 6 months and were tested for anti-HBs titer after one month of completion of vaccination. If patients showed a titer of anti-HBs <10 IU/mL, an additional 40 μg in four vaccine doses was administered immediately and they were retested for the anti-HBs following the same schedule. The patients were divided into two groups: responders and non-responders.ResultsHBsAg and anti-HCV seroprevalence was 3.4% and 10.3%, respectively. After vaccination schedule, 264 (83.5%) patients had antibody response to HBV vaccine and 52 (16.5%) had no response. Hepatitis B vaccine unresponsiveness is more common in the patients with hepatitis C positivity (p = 0.011), BMI >30 (p = 0.019), over the age of 65 years (p = 0.009), and duration of dialysis treatment >5 years (p = 0.001). There was no statistically significant difference between gender, causes of renal disease, erythropoietin treatment, and the type of dialysis.ConclusionHepatitis C infection, obesity, being elderly, and having long hemodialysis period reduced the hepatitis B vaccination response in hemodialysis patients.