Antimicrobial resistance pattern of Gram-negative bacteria of nosocomial origin at a teaching hospital in the Islamic Republic of Iran

The emergence of antimicrobial resistance is a global problem in the community and in hospitals. Antibiotic resistance of Gram-negative bacteria from nosocomial infections were evaluated during a 6-month period at Shariati teaching hospital, Tehran, Islamic Republic of Iran. Susceptibility tests were performed on 570 Gram-negative isolates obtained from clinical samples of patients infected after at least 72 hours stay in the hospital. Escherichia coli was the most frequently isolated Gram-negative organism [42.6%]. The highest rate of resistance in Gram-negative isolates was seen in the intensive care unit, with Acinetobacter spp. as the most resistant organisms. Gentamicin was the most effective antibiotic against E. coli and all other isolates, while ciprofloxacin was also effective against a wide range of other species. Antibiotic resistant Gram-negative nosocomial infection is prevalent in this teaching hospital in Tehran

Steady-state pharmacokinetic analysis of vancomycin in Iranian pediatric patients

Large inter-individual variability has been reported for vancomycin pharmacokinetics in pediatric patients. On the other hand, the pharmacokinetic parameters of vancomycin should be known in order to individualize its dosage regimen. Therefore, this study was designed and conducted to assess the steady-state vancomycin serum concentration and pharmacokinetics in a population of Iranian pediatric patients. Vancomycin serum concentration at steady-state was determined in 62 children who were treated with vancomycin intermittent intravenous infusion. Also individual steady-steady pharmacokinetic parameters [total body clearance, apparent volume of distribution and elimination half-life] were determined in 30 patients who had both peak and trough vancomycin levels assuming one-compartment model. Calculated pharmacokinetic parameters were compared among patients with different underlying diseases and also with the results of similar studies that used one-compartment pharmacokinetic model for description of serum concentration of vancomycin at steady-state. More than half of the measured vancomycin serum concentrations were outside the recommended therapeutic range. Median trough concentration was significantly lower in critically ill patients as compared to patients of other disease categories. Although critically care patients showed greater values of apparent volume of distribution and also vancomycin clearance, no statistically significant difference of the calculated pharmacokinetic parameters could be detected among different groups of patients. While calculated volume of distribution for patients of this study was greater than those of similar studies, this difference could not be considered statistically significant in the majority of disease categories. It may be concluded that design of vancomycin dosage regimens according to the recommended and general guidelines in literature [e.g. based on patient creatinine clearance] could not result in the desired therapeutic serum concentrations in the study population