[Emergence of linezolid-resistant Enterococcus faecalis strains from two inpatients in a pediatric ward].

We report herein on the isolation of three linezolid-resistant Enterococcus faecalis strains in 2011 from two pediatric inpatients at Kitasato University Hospital, Japan. Three linezolid resistant strains were isolated from two patients who shared the same room of a pediatric inpatient ward. Two linezolid resistant strains were isolated from patient A who had been treated with a total of 17,600mg of linezolid during 60 days of hospitalization (strains 1 and 2). The linezolid resistant E. faecalis persisted through the time that the patient had been discharged from the hospital. Another linezolid resistant strain was isolated from patient B who had no history of linezolid administration. The resistant strain in patient B phased out spontaneously. The minimum inhibitory concentration of linezolid in these strains ranged from 8.0 to 16.0 microg/mL. PCR amplification of the chromosomal gene encoding domain V of the 23S rRNA and subsequent nucleotide sequencing revealed that all the strains had at least one G2576T mutation. The pulse-field-gel electrophoretograms of the DNA treated with the SmaI restriction enzyme showed an identical profile suggesting that they were derived from a single resistant strain. These results suggested that the resistant strain occurred in patient A and was transmitted to patient B within the inpatient ward.

[Evaluation of antigen diagnostic kit in group A streptococcus mass infection].

We report a Food-borne group A streptococcus epidemic at Kitasato University campus on July 30 and 31, 2005, believed caused by lunch. A current mass group A streptococcus infection differing from the food-borne epidemic above occurred at Kitasato University East Hospital, also believed caused by lunch. Group A streptococcus was detected using a prompt diagnostic kit and bacterial culture from 116 clinical specimens taken from 116 patients with group A streptococcus pharyngitis at Kitasato University East Hospital on August 5, 2005. To investigate the utility of immunochromatographic detection of group A streptococcus antigen, 116 clinical specimens obtained from pharyngeal membranes by swab were examined using a prompt diagnostic kit for group A streptococcus (ImmunoCard STAT! STREP A TEST) and conventional bacterial culture. Group A streptococcus positivity differed between the two methods. Fourteen patients were found to be positive by the prompt diagnostic kit and 23 by bacterial culture. Four patients showing 1.0 x 10(6) cfu/mL estimated by the culture were difficult to diagnose with the prompt diagnostic kit,even though the detection sensitivity of this kit was 1.0 x 10(6) cfu/mL or more. Conventional bacterial culture should therefore be used in addition to the prompt diagnostic kit to detect group A streptococcus, especially in pharyngeal samples obtained from patients with pharyngitis.

[Nosocomial infection by multidrug-resistant Pseudomonas Aeruginosa (MDRP) presumably spread a radiation technician].

Isolated of multidrug resistance Pseudomonas aeruginosa (MDRP) that the receptivity pattern of the antimicrobial suscepti respectively resembled isolated from clinical specimens (sputum) in two patients of each internal medicine ward in Kitasato University East Hospital for two days from September 18 and 20, 2004. Both of bacteria were formed small colonies of a smooth-type on dollargalluskey improvement-type BTB agar plates, and the judgment of ClassB (metallo)-beta-lactamase by biochemical properties and disk diffusion method sodium mercaoto-acetic acid (SMA) was mutually corresponding. Moreover, it was same serotype C according to the serotype, and it was confirmed that it was the same bacterial strain from the molecular epidemiology analysis by Random amplified polymorphic DNA polymerase chain reaction (Random amplified polymorphic DNA polymerase chain reaction: RAPD). From the investigation of clinical backgrounds of two patients who isolated bacterial strains, September 18, 2004. 10 : 20 a.m., and 10 : 40 a.m., other chances that can become with contact infection in this hospital, except conducted X-Ray or roentgenograph of the chest and abdomen of Portable X-ray device continuously done by one radiation technician was not seen. Because it had turned out that a radiation technician who had taken charge had been neglecting the hand washing at the time of each X-Ray or roentgenograph, it was guessed the case with nosocomial infection by contact infection occurred via specific radiation technician.