Prevalence of Microorganisms Causing Septicemia and Determination of Antimicrobial Resistance in Intensive Care Unit

The objective of this study was to determine the frequency of microorganisms isolated from blood samples of patients admitted to Intensive Care Unit (ICU), and the rate of their resistance to common administered antibiotics in an Iranian ICU. One-hundred patients with Systemic Inflammatory Response Syndromes (SIRS), hospitalized in ICU of Sina Hospital, Tehran, Iran, were entered to this cross-sectional study from March 2005 to March 2006. Blood samples were taken from these patients and transferred to culture medium. After detecting the type of microorganism, minimum density for inhibition of growth of microorganisms by antibiotics, using minimum inhibitors concentration (MIC) method, was determined for ceftazidime, ceftriaxone, amikacin, ciprofloxacin, meropenem and cefepime. Culture results of 38 patients were positive (38%). Klebsiella (14 patients, 37%), coagulase negative Staphylococcus (9 patients, 23.6%), Pseudomonas and Acinetobacter (each of them recovered in 6 patients, 15.8%), Staphylococcus aureus (one patient, 2.6%) and gram positive bacilli (2 patients, 5.2%) were detected microorganism. Only Staphylococcus aureus was resistant to all studied antibiotics. Gram-negative bacilli showed resistance to all antibiotics except for amikacin and meropenem.

The rate of septicemia detected was higher in comparison to developed countries. Clinical suspicion with appropriate microbiological tests is essential for early diagnosis to prevent adverse outcomes in patients admitted to ICU.