[Detection of blaIMP and blaVIM metallo-beta-lactamases genes in pseudomonas aeruginosa strains isolated from wound of burnt patients in Tehran Shahid Motahari hospital during 2011, Iran]

During recent years, metallo-beta-lactamase [MBLs] producing Pseudomonas aeruginosa has been reported as an important cause of nosocomial infection. Also, infection with this bacterium has increased rate of mortality and health care costs. The aim of this study was to determine the antibiotic resistance pattern and to detect blaVIM and blaIMP Metallo-beta-lactamase genes in P. aeruginosa isolated from patients hospitalized in the burn ward. This descriptive study was conducted on P. aeruginosa strains isolated from patients hospitalized in the burn ward of Tehran Shahid Motahari Hospital between September and January 2011. For all MBL-producing strains, antibiotic resistance pattern was determined by disc diffusion method according to CLSI guidelines. CDDT method was used for detection of MBL [imipenem-imipenem+EDTA], and PCR and sequencing techniques were used to detect MBL genes, blaVIM and blaIMP. Eighty-three percent of 100 P. aeruginosa isolates were resistant to imipenem. Using combination disk diffusion test [CDDT] method, 48 isolates were detected to have MBL, of which 6 isolates were positive for blaIMP-1 gene, and all of them did not have blaVIM gene. Also, 4 [8.3%] patients with MBL-producing P. aeruginosa infection died in the hospital. The results of this study revealed that high percentage of P. aeruginosa strains are MBL-producer. Therefore, detection of MBL-producing strains is essential for better control and treatment of burnt patients

Serologic evidence of pertussis infection in vaccinated Iranian children

It seems that the incidence of pertussis-like illnesses is considerably increasing despite the wide coverage of immunization with the whole cell pertussis vaccine. We aimed to investigate the occurrence of pertussis in vaccinated children by measuring anti-pertussis antibodies. In this cross-sectional study, blood samples were taken from vaccinated children aged 2, 4, 6, 12, 18, and 72 months. Anti-pertussis IgG and IgA were measured by ELISA. P < 0.05 was considered significant. 725 children were enrolled in the study. Geometric mean titers for IgG that showed a slight decease after 2 months of age and increased distinctly in children aged 72 months. The frequency of the individuals whose IgG was above the determined cut-off [derived from mean+2SD] was observed in 1% of the 2, 4, and 6-month-old infants, 6% of the 12 and 18-month-olds and 12% of the 6-year -old children. Positive IgA titers were detected in 5, 9, 6, 23, 11, and 8% of children aged 2, 4, 6, 12, 18, and 72 months, respectively. Since a considerable percentage of children had high levels of anti-pertussis IgG antibodies [>/=2 SD], positive anti-pertussis IgA, and most importantly an increased level of anti-pertussis IgG geometric mean titer at 6 years of age, further investigations regarding the protection provided by the presently used pertussis vaccine seems necessary