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Publications (4)12.37 Total impact

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    ABSTRACT: The presence of microorganisms in gastric fluid in neonates at birth is postulated to reflect antenatal infection and also to be associated with the development of bronchopulmonary dysplasia (BPD). A logistic regression analysis, after controlling for other risk factors, indicated that Ureaplasma-positive infants were not at increased risk for moderate/severe BPD (adjusted odds ratio (OR): 2.58, 95% confidence interval (CI): 0.57-6.89, P = 0.12). However, the association between the presence of Ureaplasma species and the risk for moderate/severe BPD increased significantly in infants on mechanical ventilation (MV) ≥2 wk (adjusted OR: 4.17, 95% CI: 1.62-44.1, P = 0.009). An analysis using a lung injury marker indicated that Ureaplasma-positive infants with MV ≥2 wk, but not other infants, showed higher serum KL-6 levels in samples taken from cord blood, and that KL-6 levels increased time-dependently up to 4 wk of age. Antenatal exposure to Ureaplasma species induces lung injury prior to birth and synergistically contributes to the development of BPD in infants requiring prolonged MV (≥2 wk). We recovered gastric fluid specimens from 122 infants with gestational age (GA) <29 wk or birth weight <1,000 g to investigate whether these microorganisms influence respiratory outcome of BPD. A PCR analysis was used to detect urease and 16S ribosomal RNA (rRNA) genes to classify neonates into Ureaplasma-positive or Ureaplasma-negative infants.
    Pediatric Research 03/2012; 71(3):267-73. · 2.67 Impact Factor
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    ABSTRACT: We report a neonatal infection with Streptococcus dysgalactiae subsp. equisimilis occurring through maternal transmission and presenting as streptococcal toxic shock syndrome 12 hours after birth. Pediatricians and obstetricians should be aware of the possibility of this infectious disease when examining newborns with fever. These observations suggest that antenatal maternal screening for S. dysgalactiae subsp. equisimilis should be considered.
    The Pediatric Infectious Disease Journal 10/2010; 29(10):979-81. · 3.57 Impact Factor
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    ABSTRACT: Gastric fluid microbes were examined in preterm infants at birth to assess their influence on the postnatal outcome. Prospective cohort study. Level III neonatal intensive care unit. A total of 103 premature neonates with a gestational age of less than 32 weeks. Gastric fluid microbes were identified by analysis of bacterial 16S ribosomal RNA gene. Additionally, the urease gene of Ureaplasma species was detected by polymerase chain reaction of gastric fluid obtained at birth and/or tracheal aspirate from ventilated preterm infants. The association between detection of microbes and bronchopulmonary dysplasia was investigated through assessment from clinical features and by a lung injury marker (KL-6). Forty-two of 103 gastric fluid specimens were positive for microbes. Ureaplasma species were detected in 23 of the 42 (55%) gastric fluid specimens. All infants with Ureaplasma species in tracheal aspirate fluid also had positive gastric fluid specimens. Compared to infants negative for gastric fluid microbes, infants positive for microbes had higher rates of maternal chorioamnionitis (18% vs 78%), premature rupture of membranes (11% vs 55%), severe bronchopulmonary dysplasia (1.6% vs 14%) and showed higher plasma KL-6 levels during the initial 4 weeks of life. Detection of gastric fluid microbes was correlated well with antenatal infection and severe bronchopulmonary dysplasia. Detection of Ureaplasma species in gastric fluid was associated with subsequent respiratory colonisation. These results suggest that antenatal exposure of the immature fetus to microbes may cause lung injury and promote the onset of bronchopulmonary dysplasia.
    Archives of Disease in Childhood - Fetal and Neonatal Edition 09/2008; 94(1):F17-22. · 3.45 Impact Factor
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    ABSTRACT: Circulating KL-6 is a specific indicator of pulmonary injury affecting the alveolar epithelium and interstitium. Our preliminary study suggested the usefulness of plasma KL-6 as a marker of bronchopulmonary dysplasia (BPD). To confirm the diagnostic value of KL-6 for BPD as well as to determine the reference range, we conducted a larger prospective study in 135 preterm infants <32 wk GA. Among the infants without oxygen dependence at a postconceptional age of 36 wk, the plasma KL-6 level showed no significant association with GA at any time. Among 42 infants <28 wk GA, plasma KL-6 levels were significantly higher in those with moderate/severe BPD compared with those with no/mild BPD. A plasma level of 199 U/mL at 1 wk or 232 U/mL at 2 wk was an excellent predictor of moderate/severe BPD <28 wk GA (positive predictive value of 83% and 80%, respectively). Unlike nonspecific markers of inflammation or fibrosis, KL-6 objectively reflects the severity of pulmonary injury irrespective of the treatment or the radiographic changes. Therefore, not only as a good marker, measurement of KL-6 may also help to provide new insights into the pathogenesis of BPD.
    Pediatric Research 11/2006; 60(5):613-8. · 2.67 Impact Factor