Profile of antimicrobial susceptibility isolated microorganisms from hospitalized patients in PICU ward and detection of Methicillin-resistant Staphylococcus aureus and ESBL-producing bacteria by phenotypic methods

Hospital-acquired infections are a major challenge to patient. A range of gram-negative organisms are responsible for hospital-acquired infections, the Enterobacteriaceae family being the most commonly identified group overall. Infections by ESBL producers are associated with severe adverse clinical outcomes that have led to increased mortality, prolonged hospitalization, and rising medical costs. The aim of this study was to survey profile of antimicrobial susceptibility isolated microorganisms from hospitalized patients in PICU ward and detection of methicillin-resistant Staphylococcus aureus and ESBL-producing bacteria by phenotypic methods. In this study participants were patients hospitalized in PICU part of Bahrami Hospital, Tehran, with attention to involved organ. For isolation of bacteria from patient’s samples, culture performed on different selective and differential media. After confirmation of bacteria by biochemical tests, susceptibility testing was performed by disc diffusion method. Phenotypic detection of MRSA strains was performed using cefoxcitin disc. ESBL producing strains were detected by ceftazidime (CAZ) and ceftazidime/clavulanic acid (CAZ/CLA) discs. Among all isolated organisms from clinical samples, the most common isolated organisms were Escherichia coli (24 cases), Pseudomonas areoginosa (9 cases) and Staphylococcus aureus (8 cases), respectively. Among eight MRSA isolated strains from different clinical samples, six strains (75%) were MRSA. Among 52 isolated gram negative organisms, 5 strains (9/6%) were ESBL. Standard interventions to prevent the transmission of antimicrobial resistance in health care facilities include hand hygiene, using barrier precautions in the care of colonized and infected patients, using dedicated instruments and equipment for these patients. The colonized or infected patients should be isolated in single rooms, multibed rooms or areas reserved for such patients. Active surveillance screening is necessary to identify asymptomatically colonized patients who may serve as undetected reservoirs.