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.

Molecular Epidemiology of Ampicillin-resistant Haemophilus influenzae Causing Acute Otitis Media in Japanese Infants and Young Children.

BACKGROUND: Nontypeable Haemophilus influenzae is a particularly important cause of acute otitis media (AOM). There is a high prevalence of ß-lactamase-nonproducing ampicillin-resistant (BLNAR) strains in Japanese children, which is associated with recurrent AOM and prolonged treatment. The aim of this study was to investigate the antimicrobial susceptibility profile, mechanisms of ampicillin resistance and molecular epidemiology of ampicillin resistance in H. influenzae strains causing AOM in Japanese children. METHODS: One hundred fifty-seven strains of H. influenzae isolated from the middle ear fluid of pediatric patients (aged 0-3 years) with AOM from various areas of Japan were studied. The antimicrobial susceptibility profile, genes encoding ß-lactamase and alterations of penicillin-binding protein 3 were investigated. Genetic relatedness among ampicillin-resistant isolates was examined by multilocus sequence typing and pulsed-field gel electrophoresis. RESULTS: Of 157 isolates, 108 (68.8%) demonstrated reduced susceptibility to ampicillin, including 95 (60.5%) of ß-lactamase-nonproducing isolates and 13 (8.3%) of ß-lactamase-producing isolates. All BLNAR (minimum inhibitory concentration of ampicillin ≥ 4 mg/L) isolates had amino acid substitutions related to ampicillin resistance. Multilocus sequence typing and pulsed-field gel electrophoresis demonstrated genetic diversity although there were 2 clusters of highly resistant isolates with identical STs (sequence types; ST161 and 549). CONCLUSIONS: Alterations of penicillin-binding protein 3 represented the most prevalent mechanism of ampicillin resistance among H. influenzae isolates causing AOM in Japanese children. BLNAR isolates from children with AOM demonstrated genetic diversity. This study identified for the first time ST clones associated with BLNAR H. influenzae causing AOM in Japanese children.

A case of Manila type Mycobacterium tuberculosis infection in Japan.

A 76-year-old Japanese woman contracted a Mycobacterium tuberculosis (TB, Manila type) infection in Japan, despite never having traveled. However, her son was treated for TB in the Philippines 3 years before he stayed at her house. Spoligotyping allows us to identify the TB genotype and identify the route of infection.

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.

First confirmed case of spondylodiscitis with epidural abscess caused by Parvimonas micra.

Parvimonas micra was renamed species as within Gram-positive anaerobic cocci and rarely causes severe infections in healthy people. We report the first confirmed case of spondylodiscitis with epidural abscess caused by P. micra in a healthy women. The patient has a pain in low back and anterior left thigh. Magnetic resonance imaging and computed tomography detected the affected lesion at the L2 and L3 vertebral bodies. All isolates from the surgical and needle biopsy specimens were identified as P. micra by 16S rRNA and MALDI-TOF. In this case, P. micra showed high sensitivity to antimicrobial therapy. She was successfully treated with debridement and sulbactam/ampicillin, followed by oral metronidazole for a total of 10 weeks. The causative microorganisms of spondylodiscitis are not often identified, especially anaerobic bacteria tend to be underestimated. On the other hand, antimicrobial therapy for spondylodiscitis is usually prolonged. Accordingly, we emphasize the importance of performing accurate identification including anaerobic bacteria.

Impact of the Seven-valent Pneumococcal Conjugate Vaccine on Acute Otitis Media in Japanese Children: Emergence of Serotype 15A Multidrug-resistant Streptococcus pneumoniae in Middle Ear Fluid Isolates.

BACKGROUND: Streptococcus pneumoniae is one of the most common bacteria causing acute otitis media (AOM). In Japan, a 7-valent pneumococcal conjugate vaccine (PCV7) was introduced for voluntary vaccination of children in 2010, and it became a recommended vaccination in April 2013. We surveyed the serotypes and antimicrobial susceptibility profile of S. pneumoniae isolates obtained from the middle ear fluid of Japanese children with AOM. METHODS: Between April and September 2013, a total of 176 S. pneumoniae isolates were obtained from the middle ear fluid of children aged 0-3 years with AOM. Isolates were collected from various regions of Japan. Minimum inhibitory concentrations were measured by the broth microdilution method. Serotyping was performed by observing the Quellung reaction. RESULTS: Although 45.5% of the strains were susceptible to penicillin G, 42.6% were penicillin-intermediate strains and 11.9% were penicillin-resistant strains. Serotype 19A (27.3%), serotype 15A (14.2%) and serotype 3 (11.9%) showed a high frequency. Although PCV7 types only accounted for 4.5% of all strains, 44.9% were PCV13 types and 55.1% were non-PCV types. Serotype 15A strains were 100% nonsusceptible to penicillin G and all of these strains showed multidrug resistance. Serotype 15A was frequent in children up to 1 year old. CONCLUSION: After this research was completed, PCV7 was switched to a PCV13 that also contained serotype 3 and serotype 19A. We need to consider the possibility that serotype 15A, which is not included in PCV13, may increase and cause intractable AOM in the future.

A case of culture-negative endocarditis due to Streptococcus tigurinus.

Culture-negative endocarditis remains a diagnostic and therapeutic challenge despite recent medical advances. Streptococcus tigurinus, a novel member of the Streptococcus mitis group, was first identified in Zurich. S. tigurinus possesses virulence determinants and causes invasive infections. We report a case of culture-negative endocarditis with serious complications due to S. tigurinus, which was identified by 16S ribosomal RNA gene sequence analysis of excised valve tissue specimens. This technique is useful for identification of the causative microorganism in patients with culture-negative endocarditis and may facilitate early diagnosis and appropriate antimicrobial treatment.

A survey conducted immediately after the 2011 Great East Japan Earthquake: evaluation of infectious risks associated with sanitary conditions in evacuation centers.

In cooperation with the Miyagi prefectural government, we conducted a survey of the management of sanitation at evacuation centers and the health of the evacuees by visiting 324 evacuation centers at two weeks after the 2011 Great East Japan Earthquake. The facilities often used as evacuation centers were community centers (36%), schools (32.7%) and Nursing homes (10.2%). It was more difficult to maintain a distance of at least 1 m between evacuees at the evacuation centers with a larger number of residents. At evacuation centers where the water supply was not restored, hygienic handling of food and the hand hygiene of the cooks were less than adequate. Among evacuation centers with ≤50 evacuees, there was a significant difference in the prevalence rate of digestive symptoms between the centers with and without persons in charge of health matters (0.3% vs. 2.1%, respectively, p < 0.001). The following three factors had an important influence on the level of sanitation at evacuation centers and the health of evacuees: 1) the size of the evacuation center, 2) the status of the water supply, and 3) the allocation of persons in charge of health matters. Given that adjusting the number of evacuees to fit the size of the evacuation center and prompt restoration of the water supply are difficult to achieve immediately after an earthquake, promptly placing persons in charge of health matters at evacuation centers is a practicable and effective measure, and allocation of at least one such person per 50 evacuees is desirable.

High frequency of Acinetobacter soli among Acinetobacter isolates causing bacteremia at a tertiary hospital in Japan.

Acinetobacter baumannii is generally the most frequently isolated Acinetobacter species. Sequence analysis techniques allow reliable identification of Acinetobacter isolates at the species level. Forty-eight clinical isolates of Acinetobacter spp. were obtained from blood cultures at Tohoku University Hospital. These isolates were identified at the species level by partial sequencing of the RNA polymerase ß-subunit (rpoB), 16S rRNA, and gyrB genes. Then further characterization was done by using the PCR for detection of OXA-type ß-lactamase gene clusters, metallo-ß-lactamases, and carO genes. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing were also performed. The most frequent isolate was Acinetobacter soli (27.1%). Six of the 13 A. soli isolates were carbapenem nonsusceptible, and all of these isolates produced IMP-1. PFGE revealed that the 13 A. soli isolates were divided into 8 clusters. This study demonstrated that A. soli accounted for a high proportion of Acinetobacter isolates causing bacteremia at a Japanese tertiary hospital. Non-A. baumannii species were identified more frequently than A. baumannii and carbapenem-nonsusceptible isolates were found among the non-A. baumannii strains. These results emphasize the importance of performing epidemiological investigations of Acinetobacter species.

Tuberculosis exposure among evacuees at a shelter after earthquake, Japan, 2011.

Tuberculosis was diagnosed in a person who had stayed in a shelter after the 2011 Great East Japan Earthquake. A contact investigation showed that the prevalence of latent tuberculosis infection among other evacuees at the shelter was 20%. Our report underscores the importance of tuberculosis prevention and control after natural disasters.

Molecular characteristics of extended-spectrum ß-lactamases in clinical isolates from Escherichia coli at a Japanese tertiary hospital.

The prevalence of ESBL has been increasing worldwide. In this study, we investigated the molecular characteristics of ESBL among clinical isolates of Escherichia coli from a Japanese tertiary hospital. A total of 71 consecutive and nonduplicate clinical isolates of ESBL-positive E. coli collected at Tohoku University Hospital between January 2008 and March 2011 were studied. The antimicrobial susceptibility profile of these strains was determined. PCR and sequencing were performed to identify genes for ß-lactamase (bla(TEM), bla(SHV), bla(OXA-1-like), and bla(CTX-M)) and plasmid-mediated quinolone resistance determinants (PMQR). The isolates were also analyzed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Of the 71 strains, 68 were positive for CTX-M, 28 were positive for TEM, four were positive for OXA-1, and one was positive for SHV. Sequencing revealed that CTX-M-14 was the most prevalent (31/71), followed by CTX-M-27 (21/71) and then CTX-M-15 (9/71). Of the 28 TEM-positive strains, one was TEM-10 and the rest were TEM-1. One SHV-positive strain was SHV-12. The 21 CTX-M-27-producing isolates were divided into 14 unique PFGE types, while the 9 CTX-M-15 producers were divided into 8 types. Based on MLST, 9 CTX-M-14 procedures, 19 CTX-M-27 procedures, and 8 CTX-M-15 producers belonged to ST131. Thirty-five (94.6%) of the 37 ST131 E. coli strains showed resistance to levofloxacin, which was a higher rate than among non-ST131 strains (63.6%). Among ESBL-producing isolates, one, two, and six possessed qnrB, qnrS, qepA, and aac(6')-Ib-cr, respectively. Of the 6 isolates with aac(6')-Ib-cr, 4 carried the CTX-M-15 gene. Our data suggest that CTX-M-15-producing E. coli ST131 has emerged as a worldwide pandemic clone, while CTX-M-27 (a variant of CTX-M-14) is also spreading among E. coli ST131 in Japan.

Characteristics of infectious diseases in hospitalized patients during the early phase after the 2011 great East Japan earthquake: pneumonia as a significant reason for hospital care.

BACKGROUND: Natural catastrophes increase infectious disease morbidity rates. On March 11, 2011, a 9.0-magnitude earthquake and associated Pacific coast tsunami struck East Japan. The aim of this study was to investigate the characteristics of patients with infectious diseases who needed hospitalization after this disaster. METHODS: We searched the medical records of 1,577 patients admitted to Tohoku University Hospital in the Sendai area within 1 month (March 11, 2011-April 11, 2011) after the disaster. We examined (1) changes in the rates of hospitalizations for infectious diseases over time and (2) the variety of infectious diseases. RESULTS: The number of hospitalized patients with infectious diseases increased after the fi rst week to double that during the same period in 2010. Pneumonia comprised 43% of cases, and 12% consisted of skin and subcutaneous tissue infection, including tetanus. Pneumonia was prevalent in elderly patients (median age, 78 years) with low levels of serum albumin and comorbid conditions, including brain and nervous system disorders. Sputum cultures contained Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae , known pathogens of community-acquired pneumonia in Japan. In addition, 20.5% of patients had positive results for urinary pneumococcal antigen. CONCLUSIONS: Among hospitalized patients, infectious diseases were significantly increased after the disaster compared with the same period in 2010, with pneumonia being prominent. The analyses suggest that taking appropriate measures for infectious diseases, including pneumonia, may be useful for disaster preparedness and medical response in the future.

Post-tsunami outbreaks of influenza in evacuation centers in Miyagi Prefecture, Japan.

We describe 2 post-tsunami outbreaks of influenza A in evacuation centers in Miyagi Prefecture, Japan, in 2011. Although containment of the outbreak was challenging in the evacuation settings, prompt implementation of a systemic approach with a bundle of control measures was important to control the influenza outbreaks.

[Severe community-acquired pneumonia due to Acinetobacter baumannii].

A 78-year-old man with COPD was admitted in August 2010 complaining of productive cough and fever of 38 degrees C for 2 days. He was admitted with septic shock and pneumonia of the right upper lobe. Despite antibiotic administration, infiltration progressed to the right lung and lower left lung after 24 hours, and he developed acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation. All cultures from both sputum and blood grew Acinetobacter baumannii. He recovered following intensive care. Although some community-acquired pneumonias by A. baumannii are reported in Japan, this is the first report concerning a successfully treated patient.