Evaluation of the FilmArray Blood Culture Identification Panel on Detection of Pathogenic Microorganisms in Positive Blood Cultures: the First Clinical Report in Japan.

FilmArray (FA) is a multiplex PCR-based desktop microbial detection system. The blood culture identification (BCID) panel is an adaptable panel for FA, which diagnoses sepsis and/or systemic infections by detecting 14 bacterial species, 4 bacterial genera, 1 bacterial family, 5 yeast species, and 3 antimicrobial resistance genes (mecA, Klebsiella pneumoniae carbapenemase [KPC], and vanA/B) in positive blood cultures within 1 h. We retrospectively evaluated the FA-BCID panel using 54 positive blood cultures, in which 57 bacterial and 3 yeast strains were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The FA-BCID panel revealed 59 microorganisms in 53 samples; this performance was similar to that of MALDI-TOF MS analysis; however, 1 bacterium in 1 sample was not detected. In addition, mecA genes were detected in 12 Staphylococcus species, which all manifested methicillin resistance in susceptibility testing, whereas genes KPC and vanA/B were not detected, in agreement with the results of antimicrobial susceptibility testing. Although more information on antimicrobial resistance, including activity of IMP-metallo-ß-lactamases, is required in Japan, the FA-BCID panel can detect pathogenic microorganisms in positive blood cultures rapidly, and this method could be beneficial for proper treatment of sepsis and/or systemic infections, especially in small hospitals.

Microbiological and molecular epidemiological analyses of community-associated methicillin-resistant Staphylococcus aureus at a tertiary care hospital in Japan.

Molecular characterization of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is generally conducted referred to staphylococcal cassette chromosome mec (SCCmec) type IV or V. CA-MRSA is now a cause of concern since such strains have been isolated not only from individuals in a community but also from patients in healthcare settings. The aim of this study was to analyze microbiological and molecular epidemiological features of CA-MRSA strains at a Japanese tertiary care hospital using PCR based-open reading frame typing (POT). This technique allows for molecular classification into CA-MRSA (POT-CA) and hospital-associated (HA-) MRSA (POT-HA) with clonal discrimination. Clinical MRSA isolates obtained from consecutive patients between October 1, 2012 and September 30, 2013 at the hospital were analyzed in combination with the clinical definition for CA-MRSA by the Centers for Disease Control and Prevention and POT. Of 219 isolates (76 clonal groups), 64 (29.3%) were clinical-HA/POT-CA isolates (22 clonal groups). Some clones of them accumulated in this hospital and might be involved in nosocomial transmission. Virulent factors of the isolates were analyzed, and only one (1.6%) Panton-Valentine leukocidin gene positive isolate but no arginine catabolic mobile element genes positive isolate were found in clinical-HA/POT-CA. Additionally, clinical-HA/POT-CA isolates showed higher antimicrobial susceptibility than clinical-HA/POT-HA, especially to minocycline, doxycycline, and amikacin. The most frequent genotype of molecular CA-MRSA was multi-locus sequence type 5-SCCmecIV, previously not detected in Japan. Although CA-MRSA at this hospital showed low virulence and higher antimicrobial susceptibility, the risk of nosocomial infection from them should be recognized, requiring stricter infection control measures.

Prevaccination antibody screening and immunization program for healthcare personnel against measles, mumps, rubella, and varicella in a Japanese tertiary care hospital.

Susceptible healthcare personnel (HCP) are at high risk for acquiring and transmitting measles, mumps, rubella, and varicella (MMRV). Presumptive evidence of immunity to MMRV is recommended for HCP. The aim of this investigation was to examine the seroprevalence of MMRV in Japanese HCP and the association with history or vaccination in terms of occupational safety. To improve infection control at our hospital, we also assessed their immune status by implementing prevaccination antibody screening and an immunization program with postvaccination serological testing. We implemented seroprevalence surveys on MMRV antibodies among 243 newly and 2,664 previously hired HCP in a Japanese tertiary care hospital. Self-administered questionnaires about history of MMRV and vaccination with or without written documentation were completed for newly hired HCP. Prevaccination and postvaccination serological tests were performed using virus-specific IgG enzyme-linked immunosorbent assays. Indeed, only a few HCP accurately remembered or had written records of their disease or vaccination history. After our immunization program was implemented, the seropositivity rate reached levels as high as ~98% for measles, rubella, and varicella, and increased to ~80% for mumps. Our program was cost-effective, and no severe adverse reactions were reported. The prevaccination antibody screening for HCP would be helpful, given the lack of written vaccination records or documented disease history, and is also useful for the prevention of adverse reactions associated with unnecessary vaccination. It is important for infection control practitioners to comprehend the immune status of HCP against MMRV, and then provide an appropriate immunization program for susceptible HCP.