Background: The aim of this study was to determine the minimal
inhibitory concentration (MIC) of microorganisms causing nosocomial
infections in the pediatric intensive care unit (PICU) of the
Children's Medical Center in Tehran. Methods: All patients with
nosocomial infections in the PICU were enrolled in the study. Causative
microoraganisms were coagulase positive, and coagulase negative
Staphylococci and Pseudomonas aeruginosa . MIC of many antibiotics
was determined by microbroth dilution according to NCCLS. Findings:
Within a period of 18 months, thirty patients developed nosocomial
infection including 17 cases with P.aeruginosa and 9 individuals with
Staph aureus infection. The remaining 4 patients were involved with
coagulase negative Staphylococci. The most common sources were
respiratory tract, blood stream, wound and soft tissue.
Multi-antimicrobial resistance (resistance to Amikacin, Ceftazidim,
Imipenem and Ciprofloxacin) was common among P. aeruginosa species All
strains of Staph aureus were resistant to Methicillin (MRSA). These
microorganisms were also resistant to clindamycin and ciprofloxacin in
88% of cases.Conclusion: Resistance to antimicrobial agents was high in
our study, therefore routine MIC examination is necessary in PICU
