Antimicrobial susceptibility patterns of the gram-negative bacteria isolated from septicemia in Children's Medical Center, Tehran, Iran.

INTRODUCTION: The choice of antimicrobial treatment for septicemia is often empirical and based on the knowledge of local anti-microbial activity patterns of the most common bacteria causing such bloodstream infections. The current study aimed to study the prevalence of bacterial pathogens causing septicemia and their antimicrobial resistant profiles in hospital admitted patients. METHODS: This cross sectional study done at Children's Medical Center, Tehran, Iran. We examined 168 bacterial strains isolated from 186 clinically diagnosed septicemia cases refereed at Children's Medical Center, Tehran, Iran. Over a period of twelve months from July 2010 to 2011 July. 11446 blood samples from patients of clinically suggestive septicemia were evaluated. RESULTS: Bacterial strains were isolated from 910 (7.95%) of blood cultures. Gram-negative bacteria identified were Pseudomonas species (20.5%), Pseudomonas aeruginosa (1.86%), Salmonella spp (1.09%), Acinetobacter naumannii (8.13%), Escherichia coli (4.06%), Klebsiella spp (5.16%). Gram-negative pathogens were more than gram positive in bloodstream infections. Antimicrobial susceptibility testing was done according to Clinical and Laboratory Standards Institute (CLSI, USA) guidelines against: amikacin ampicillin, amoxicillin, amoxiclav, cefuroxime, cefotaxime, ceftazidime, cefoperazone tetracycline, chloramphenicol, ciprofloxacin, gentamicin. Resistanc to different antibiotics in the most important isolated bacteria were: 32.1%, 10.8%, 87.8%, 96%, 39.1%, 35.2, 49.4%, 69%, 80.02%, 22%, 59%, 30.1% respectively, for Pseudomonas spp, 32%, 3.7%, 84.2%, 83.2%, 80.1%, 75.4%, 44.8%, 45.2%, 33.3%, 19%, 34.1, 11.5% respectively for Acinetobacter species. DISCUSSION: Resistant to majority of the antimicrobial agents for several pathogens implicated in bloodstream infections, particularly in Gram-negative bacteria, can make complication in treatment of infection cause by them.

A molecular survey on virulence associated genotypes of non-O1 non-O139 Vibrio cholerae in aquatic environment of Tehran, Iran.

Thirty-seven Vibrio cholerae strains were isolated from surface water sources at 5 different locations in Tehran, Iran during 2006 and were identified as non-O1 and non-O139 isolates. PCR for SXT element and class 1 integron was positive for 19% and 5.4% of isolates, respectively. PCR for virulence associated-genes within the vibrio pathogenicity island (VPI) gene cluster showed the presence of LJ, int and RJ in 8, 59 and 30% of the isolates, respectively. None of the V. cholerae isolates contained the toxin encoding genes (ace, zot, ctx) in the CTX genetic element. Biochemical fingerprinting using PhPlate system (PhP-RV) was able to type all strains and resulted in 8 common types (containing 78% of the isolates) and 8 single types (22%). Out of 37 isolates, only 26 isolates were typeable with pulsed-field gel electrophoresis (PFGE) producing banding patterns. The results presented in this study showed no genotyping correlation between the V. cholerae isolated from surface water and the clinical setting which had been reported previously by this laboratory. Furthermore, combination of PFGE and PhP-RV methods was proved beneficial for non-typeable V. cholerae isolates.

Characteristics of dermatophytoses among children in an area south of Tehran, Iran.

The aim of this study was to determine the prevalence and etiological agents of dermatophytoses, and also their distribution according to age, gender, and body site among children in an area south of Tehran. A total of 382 children aged