Mitsuaki Hosoya

Fukushima Medical University, Hukusima, Fukushima, Japan

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Publications (132)269.76 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: AimSome patients with severe IgA nephropathy (IgAN) are resistant to multi-drug combination therapy; however, there have been few reports on the risk factors for non-responsiveness to treatment for severe IgAN. We, therefore, evaluated the risk factors for non-responsiveness to treatment in cases of severe IgAN.Methods We collected data on 44 children who had been diagnosed with IgAN with diffuse mesangial proliferation and treated with multi-drug combination therapy. The children were divided into two groups based on the prognosis at the latest follow-up. Group 1 consisted of 30 children with normal urine and 9 children with minor urinary abnormalities and Group 2 consisted of 4 children with persistent nephropathy and one child with renal insufficiency. The clinical, laboratory, and pathological findings for both groups were analyzed.ResultsThe age at the onset in Group 2 was higher than that in Group1. C3 deposits and high chronicity index values at the first renal biopsy were more frequently found in Group 2 than in Group 1 patients. IgA deposits, serum IgA and MRP 8/14 levels, and glomerular and interstitial MRP8+CD68+ scores at the second biopsy were all higher in Group 2 than in Group 1 patients.Conclusions Our results, although based on only a small number of patients in a retrospective study, suggest that age, presence of C3 deposits and interstitial changes at the onset, and persistent renal inflammatory activation may be risk factors for non-responsiveness to treatment for IgAN with diffuse mesangial proliferation.
    Nephrology 03/2014; · 1.69 Impact Factor
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    ABSTRACT: Most wheezing episodes in infants are caused and exacerbated by virus-induced lower respiratory tract infections. However, there are few reports of epidemiologic and clinical virus-specific research with a focus on virus-induced wheezing. The purpose of the current study was to characterize the clinical presentation of virus-induced wheezing in pediatric patients <3 years of age who were hospitalized with lower respiratory tract infections. Of the 412 patients in the study, 216 were followed for 3 years. Nasopharyngeal aspirates collected from the patients at the time of admission were examined for the presence of respiratory syncytial virus (RSV), rhinovirus (RV), parainfluenza-3 virus (PIV-3), human metapneumovirus (hMPV), and influenza virus (Flu) using reverse-transcription polymerase chain reaction and rapid diagnostic tests. Clinical signs were assessed using a severity scoring system. In patients with wheezing at the time of admission, RSV, RV, RSV+RV, Flu, PIV-3, and hMPV were detected in 33, 14, 8, 8, 5, and 3 % of samples, respectively. There were no differences in age and severity scores between patients harboring more prevalent viruses (RSV and RV) and those with less common infections. Patients with wheezing and RV-positive aspirates at the time of admission were more likely to develop subsequent wheezing during the following 3 years. Conclusion: RSV and RV infections are factors in the development and exacerbation of wheezing after virus-induced lower respiratory tract infections. Moreover, RV-induced wheezing may be associated with subsequent recurrent wheezing and the development of asthma.
    European Journal of Pediatrics 02/2014; · 1.91 Impact Factor
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    ABSTRACT: The incidence of obesity-related glomerulopathy (ORG) has increased over the last decade, but there have been few reports on ORG in Japanese children. Reported herein are two children with ORG identified on school urinary screening (SUS). Patient 1 was a 12-year-old boy in whom proteinuria was first detected on SUS. His body mass index (BMI) was 33.8 kg/m(2) and he had hypertension and hyperuricemia. Patient 2, a 10-year-old boy, also had proteinuria identified on SUS. His BMI was 34.8 kg/m(2) , and he had fatty liver, hyperuricemia, and hypercholesterolemia. Both were diagnosed with ORG based on obesity, proteinuria, and renal pathological findings. After treatment, including candesartan, food restriction and physical exercise, urinary protein excretion was decreased in both cases. We believe that such school urinary screening programs may be effective for the early identification and treatment of children with ORG.
    Pediatrics International 02/2014; 56(1):115-8. · 0.88 Impact Factor
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    ABSTRACT: Myeloid/natural killer cell precursor acute leukemia (MNKL) is an aggressive disease with a high relapse rate even after allogeneic hematopoietic stem cell transplantation (SCT). We report a patient with MNKL who had a donor lymphocyte infusion (DLI) for relapse after T cell-replete human leukocyte antigen (HLA)-haploidentical SCT, but relapsed again 20 months later with loss of mismatched HLA. This case suggests that a strong graft-versus-leukemia effect of haploidentical SCT can be expected in MNKL patients. In the haploidentical setting, DLI should be considered for patients with relapsed leukemia whose leukemic cells have not lost HLA cell surface expression. Pediatr Blood Cancer © 2014 Wiley Periodicals, Inc.
    Pediatric Blood & Cancer 01/2014; · 2.35 Impact Factor
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    ABSTRACT: The objective of this study was to estimate the efficacy of the neuraminidase (NA) inhibitors (NAIs) oseltamivir and zanamivir for decreasing viral load and to investigate whether NAI treatment decreases viral susceptibility to NAIs over time in children with influenza B virus infection. Of 27 patients with influenza B virus infection, 8 and 9 were treated with oseltamivir and zanamivir, respectively, whereas 10 received no NAI. Nasal aspiration samples, collected every morning until negative antigen results in two consecutive samples were observed, were subjected to viral load measurements by quantitative real-time reverse transcription-polymerase chain reaction and viral susceptibility to NAI by NA inhibition assays. Viral load decreased in both the oseltamivir and zanamivir groups by day 2 but increased in the no-NAI treatment group. Viral load in the oseltamivir and zanamivir groups on day 5 was 2.6% and 9.2% of that on day 0, respectively, whereas it was 26.4% in the no-NAI treatment group. Mean 50% inhibitory concentration (IC50) values of oseltamivir and zanamivir in the no-NAI treatment group were 5.0-6.6 and 1.3-1.8 nM, respectively. Mean IC50 values of oseltamivir and zanamivir in patients treated with oseltamivir and zanamivir were 3.9-8.8 and 1.3-1.8 nM, respectively. No major decrease in viral susceptibility to NAIs was observed during or after NAI treatment. NAI treatment was effective for inhibiting viral replication during the early days of illness and did not decrease viral susceptibility to NAIs in patients with influenza B virus infection.
    The Pediatric Infectious Disease Journal 01/2014; · 3.57 Impact Factor
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    ABSTRACT: Recombinant human soluble thrombomodulin (rhTM) is a promising therapeutic natural anticoagulant and is used clinically for the treatment of disseminated intravascular coagulation (DIC). Herein is reported the cases of two HUS children treated with rhTM. The patients were diagnosed as having typical HUS on the basis of thrombocytopenia, hemolytic anemia, acute renal failure, and the detection Escherichia coli 0157. I.v. rhTM was started as an anti-coagulant drug. At 2 days after the first treatment in both patients, fibrin/fibrinogen degradation products and d-dimer levels were significantly decreased, and there was a subsequent slight improvement in thrombocytopenia, and a decrease in serum lactate dehydrogenase level. Urinary protein excretion gradually diminished and a decrease in serum creatinine level was observed. The patients did not require dialysis therapy. The present results suggest that rhTM may be a safe and effective treatment for DIC complicated with HUS in children.
    Pediatrics International 10/2013; 55(5):e139-42. · 0.88 Impact Factor
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    ABSTRACT: Hyperammonemia of newborns should be treated promptly, and the outcome depends on the rapid elimination of excessive plasma ammonia. We encountered a case of transient hyperammonemia in an extremely low-birthweight infant whose plasma ammonia decreased sufficiently after continuous hemodialysis therapy. It seems that continuous hemodialysis therapy using the peripheral artery and umbilical vein is useful for hyperammonemia of extremely low-birthweight infants; however, there are several problems to consider due to the immaturity of these infants.
    Pediatrics International 10/2013; 55(5):656-8. · 0.88 Impact Factor
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    ABSTRACT: There have been a number of reports on large outbreaks of hemolytic uremic syndrome (HUS), however, there have been no reports of long-term studies on sporadic HUS in Japan. We examined the epidemiology and prognosis of HUS in Fukushima Prefecture over a 26-year period. We collected the medical records of 26 patients with HUS between 1987 and 2012. These children were divided into two groups: the D+HUS (n=24) and D-HUS (n=2) groups. The D+HUS group was further subdivided into Group A (11 patients requiring dialysis) and Group B (13 patients not requiring dialysis). The epidemiological and clinical data, as well as prognosis were retrospectively investigated for each group. About 90% of HUS patients belonged to the D+HUS group. In this group, the mean number of patients per year from 1987 to 1999, and from 2000 to 2012 was 0.92±0.95, and 1.08±0.86, respectively. Laboratory findings on admission showed that lactate dehydrogenase (LDH), alanine aminotransferase (ALT), blood urea nitrogen (BUN), serum creatinine and serum fibrinogen degradation product (FDP) levels in Group A were all higher than those in Group B. Serum albumin (g/dl) level and estimated glomerular filtration rate (e-GFR) in Group A were lower than those in Group B. At 6 months after the onset of HUS in the D+HUS group, renal function was normal. Our findings suggest that the frequency of HUS was constant from 1987 to 2012 in Fukushima and that serum LDH, ALT, BUN, creatinine, and FDP levels as well as e-GFR might be risk factors for dialysis in D+HUS children.
    Pediatrics International 08/2013; · 0.88 Impact Factor
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    ABSTRACT: Here we report the case of a 9-year-old boy with acute respiratory distress syndrome (ARDS) caused by novel H1N1 swine-origin influenza virus A. A diagnosis of ARDS caused by a novel influenza A (H1N1) virus was made on the basis of chest X-ray and computed tomography together with low oxygenation index (OI) and the detection of novel influenza A (H1N1) virus from tracheal secretion samples. Oseltamivir phosphate and prone positioning were effective in the treatment of ARDS in this case. These findings suggest that anti-viral drugs and prone positioning can play an important role in the improvement of ARDS caused by novel H1N1 swine-origin influenza virus A.
    Pediatrics International 06/2013; 55(3):e77-80. · 0.88 Impact Factor
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    ABSTRACT: Reported herein is a case of relapse of nephrotic syndrome (NS) after intravitreal injection of bevacizumab, a monoclonal antibody that binds to vascular endothelial growth factor (VEGF), in a 16-year-old girl. She had a diagnosis of steroid-dependent NS and had been treated with prednisolone, and remained in remission. The patient had had visus brevior 10 years previously, and was diagnosed with severe myopic choroidal neovascularization (mCNV). Intravitreal bevacizumab was given for mCNV. At 9 days after intravitreal injection of bevacizumab, proteinuria was positive. The patient had relapse of NS caused by bevacizumab, and steroid pulse therapy was then given and the proteinuria resolved. It is necessary to take particular care to prevent NS relapses in patients with mCNV treated with intravitreal bevacizumab.
    Pediatrics International 06/2013; 55(3):e46-8. · 0.88 Impact Factor
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    ABSTRACT: Measles virus (MV) isolates from patients with subacute sclerosing panencephalitis (SSPE) differ from wild-type MV virologically. However, few animal models have reported viruses with characteristics of the SSPE virus.The MV Edmonston strain was inoculated into the subarachnoid space of nude mice. All nude mice displayed weight loss and required euthanasia, with a mean survival duration of 73.2 days. The viral load in the brain was 4-400-fold higher than the inoculated load, and brain infection was confirmed by immunostaining. Gene sequencing of the viruses revealed that amino acid mutations occurred more frequently in matrix proteins. The most common mutation was a uridine-to-cytosine transition. The virus exhibited lower free virus particle formation ability than the Edmonston strain. When nude mice were challenged with 2 × 10(2) plaque-forming units (PFU) of the brain-derived virus, the mean survival duration was 34.7 days, which was significantly shorter than that of the mice challenged with 4 × 10(4) PFU of the Edmonston strain (P < 0.01).This study indicated that MV in a nude mouse model of persistent infection exhibited characteristics of the SSPE virus. This model may prove useful in elucidating the pathogenic mechanism of SSPE and developing potential therapeutics.
    Journal of Virology 01/2013; · 5.08 Impact Factor
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    ABSTRACT: Aggressive treatment is necessary for continuous high-range proteinuria in cases of pediatric Henoch-Schönlein purpura nephritis (HSPN) as the long-term prognosis is sometimes poor. Cyclosporine (CyA) has immunosuppressive effects as well as a very selective inhibitory effect on T-helper cell function. Here we report two 7-year-old boys with steroid-resistant HSPN treated with CyA. After diagnosis of HSPN, we treated both patients with methylprednisolone and urokinase pulse therapy (MUT) combined with multiple drugs; however, high-range proteinuria persisted and CyA was added to the treatment regimen. The proteinuria subsequently decreased gradually and pathological findings at the second renal biopsy were improved. Furthermore, neither patient showed any adverse effects, such as hypertension, encephalopathy, or chronic nephrotoxicity, to the CyA treatment.In conclusion, these results suggest that CyA may be a safe and effective treatment for steroid-resistant severe HSPN.
    Fukushima journal of medical science 01/2013; 59(2):102-7.
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    ABSTRACT: Henoch-Schönlein purpura (HSP) is a systemic disorder characterized by leukocytoclastic vasculitis involving the capillaries and the deposition of IgA immune complexes. Renal involvement is the principal cause of morbidity and mortality in children with HSP. Thus, it is important to clarify the onset mechanism as well as the prognostic factors of Henoch-Schönlein purpura nephritis (HSPN) and to identify the most appropriate treatment. We herein review the pathogenesis, the prognostic factors and treatment of HSPN. As to the pathogenesis, several studies suggest that galactose-deficient IgA1 (Gd-IgA1) is recognized by anti-glycan antibodies, leading to the formation of circulating immune complexes and their mesangial deposition, thereby inducing renal injury. With regard to the prognostic factors, a number of factors have been suggested including nephrotic syndrome, decreased factor XIII activity, hypertension, severe renal injury, high renal accumulation of activated macrophage, alpha-smooth muscle actin, and high serum myeloid-related protein levels.For the treatment of severe HSPN, aggressive therapies including multiple drug combination therapy and plasmapheresis have been shown to be effective in ameliorating proteinuria and histological severity. Nevertheless, detailed investigation into the pathogenesis of HSPN and double-blind randomized control studies on children with HSPN are still necessary.
    Fukushima journal of medical science 01/2013; 59(1):15-26.
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    ABSTRACT: Abstract Background: Although glucocorticoid hormones play important roles in fetal development, the expression of their receptors in the whole blood of preterm infants remains unknown. Objectives: The aim of this study was to investigate the levels of glucocorticoid receptor (GR) α and β in the whole blood of preterm and term infants. Study design: The study group consisted of 131 infants, of which 54 (41%) were preterm. Whole blood from preterm and term infants was analyzed by real-time PCR to monitor the levels of each receptor mRNA. Results: GRβ mRNA were detected in 96.6% and GRα mRNA in 100% of participants. The GRα and GRβ isoforms were detected at a ratio of 1:0.0002. GRβ mRNA/GAPDH expression in preterm infants was significantly higher than that in term infants (p=0.002). There was significant correlation between GRα/GRβ ratio and birth weight in preterm infants (rs=0.317, p=0.019), as well as between GRβ/GAPDH expression and birth weight (rs=-0.296, p=0.030). Furthermore, in preterm infants, GRβ/GAPDH expression was higher in those with SGA than in those without SGA (p=0.022). Conclusion: Importantly, in preterm infants, both the expression of GRβ and the GRα/GRβ ratio were associated with birth weight. Further studies with larger populations are necessary to determine the relation between the expression of GR and the clinical relevance of preterm infants.
    Journal of pediatric endocrinology & metabolism: JPEM 12/2012; · 0.75 Impact Factor
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    ABSTRACT: BACKGROUND: The objective of this study was to evaluate the efficacy and safety of our combination therapy in febrile neutropenic children with cancer. METHODS: A total of 109 patients with 251 episodes of febrile neutropenia received antibiotic therapy between January 2003 and December 2008 at a single institution. RESULTS: Blood cultures were positive in 35 episodes (14%). Gram-positive organisms predominated (23/38 organisms isolated). There were 15 gram-negative isolates and no fungal isolates. The recommended empirical first-line antibiotics (cefepime or cefozopran + piperacillin + amikacin) were used in 206 (82%), second-line antibiotics (piperacillin-tazobactam + carbapenem + amikacin + micafungin) in 73 (29%), and third-line antibiotics (meropenem + glycopeptides + micafungin) in 24 (10%) episodes. The overall response rates were 71.4%, 50.7%, and 62.5% for the first-, second-, and third-line antibiotic therapies respectively. Granulocyte transfusion was performed in 7 patients, and the response rate was 57%. Four deaths were recorded. CONCLUSIONS: Although a significant improvement of mortality was not observed, our regimen of empirical antibiotic therapies led to a significant and clinically relevant decrease in glycopeptide use, and it is safe and well tolerated by pediatric neutropenic patients.
    Pediatrics International 12/2012; · 0.88 Impact Factor
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    ABSTRACT: Background/Aims: The recovery process from renal injury in hemolytic uremic syndrome (HUS) remains obscure. In order to clarify the role of vascular endothelial growth factor (VEGF) and angiopoietin 1 (Ang-1) in the renal recovery from HUS, we produced a model of mild HUS and examined the renal recovery process. Methods: We investigated three groups of mice. Group 1 consisted of mice that received an injection of Shiga toxin 2 (Stx2) and lipopolysaccharide (LPS); group 2 consisted of mice that received an injection of low dose of Stx2 and LPS, and group 3 consisted of control mice. Results: Serum Cr levels in group 1 were greater than those in group 2, and all mice in group 1 died, whereas all mice in group 2 remained alive. Endothelial injury at 24 h in group 1 was higher than in group 2. Electron-microscopic findings demonstrated that the endothelial cells formed immature capillary-like lumina from 7 to 28 days with increases in the expression of CD31-positive cells. Glomerular VEGF expression decreased at 72 h in group 1, but gradually increased in group 2. Glomerular Ang-1 expression peaked from 72 h to 28 days. Ang-1 expression was frequently found in the endothelial cell region of vesicle walls simultaneous with increased CD31-positive staining. Conclusion: Our findings suggest that VEGF and Ang-1 play important roles in the recovery process, particularly in the regeneration of endothelial injury.
    American Journal of Nephrology 11/2012; 36(6):516-523. · 2.62 Impact Factor
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    ABSTRACT: Minocycline pleurodesis was performed on five infants with congenital chylothorax in our institutions. They could not achieve sufficient efficacy though they had received other conservative therapies. Four of the five cases obtained reduction of pleural effusion using the minocycline pleurodesis. We concluded that minocycline pleurodesis is a safe and an effective technique for congenital chylothorax.
    AJP reports. 11/2012; 2(1):25-8.
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    ABSTRACT: INTRODUCTION: Pulmonary interstitial emphysema is a serious complication of mechanical ventilation and can become life-threatening if progression occurs. Therapeutic lung puncture is a treatment option for severe pulmonary interstitial emphysema but has a limited use in babies with extremely low birth weight. We present a case of pulmonary interstitial emphysema in a Japanese baby (1-day-old) boy with extremely low birth weight. The emphysema was successfully decompressed by therapeutic lung puncture performed with a trocar catheter. CASE PRESENTATION: The baby was born with a weight of 420g, which, to the best of our knowledge, is the lowest reported birth weight among babies with pulmonary interstitial emphysema. A chest X-ray on postnatal day 2 revealed pulmonary interstitial emphysema, which gradually progressed to diffuse pseudocystic changes. His condition became life-threatening despite the use of high-frequency oscillatory ventilation and lateral decubitus positioning. We evacuated the pulmonary interstitial emphysema by lung puncture with a trocar catheter to avoid respiratory and cardiovascular collapse. This resulted in adequate evacuation of the emphysema and a dramatic improvement in his clinical condition. CONCLUSIONS: Therapeutic lung puncture performed with a trocar catheter is beneficial in babies with extremely low birth weight and diffuse pulmonary interstitial emphysema. This treatment option may be broadly applicable, especially in an emergency situation.
    Journal of Medical Case Reports 09/2012; 6(1):325.
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    ABSTRACT: It has not been clarified if there is a correlation between rhinovirus (RV) load and disease severity in the lower respiratory tract infections of hospitalized children. This study was undertaken to elucidate the contribution of the viral load to the development of disease severity in 412 children ≤3 years of age who were hospitalized with lower respiratory tract infections. The RV load in nasopharyngeal aspirates obtained from the patients at the time of admission was measured by real-time quantitative reverse-transcription polymerase chain reaction (PCR), and the clinical symptoms of the patients were assessed using a severity scoring system. Of the 412 patients, 43 (10.4%) were diagnosed with RV infections only, and 15 were determined to have high severity scores. When all patients infected with RV were assessed, there was no correlation between the viral load and the disease severity. However, there was a significant negative correlation between the disease severity and age among children <11 months of age (n = 15, ρ = -0.677, P = 0.006) and a significant positive correlation between the viral load and the disease severity among children ≥11 months of age (n = 28, ρ = 0.407, P = 0.032). Among the patients infected with RV <11 months of age, the disease severity may be associated with an immature immune response and the small diameter of their airways rather than viral load. By contrast, in the patients ≥11 months of age, viral load may contribute to the development of disease severity.
    Journal of Medical Virology 07/2012; 84(7):1135-42. · 2.37 Impact Factor
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    ABSTRACT: We describe a fatal case of mumps virus-associated acute encephalopathy. In terms of the clinical course and cytokine as well as chemokine profiles, the pathogenesis in our case was different from that of mumps meningoencephalitis but was similar to that of influenza virus-associated acute encephalopathy.
    Journal of child neurology 04/2012; · 1.59 Impact Factor

Publication Stats

877 Citations
269.76 Total Impact Points


  • 1998–2014
    • Fukushima Medical University
      • • Department of Pediatrics
      • • Division of Medicine
      Hukusima, Fukushima, Japan
  • 2011
    • National Institute of Infectious Diseases, Tokyo
      Edo, Tōkyō, Japan
  • 1993
    • Tokushima Bunri University
      • Faculty of Pharmaceutical Sciences
      Tokushima-shi, Tokushima-ken, Japan
  • 1992
    • KU Leuven
      • Department of Biomedical Kinesiology
      Leuven, VLG, Belgium
    • University of South Florida
      • Department of Chemistry
      Tampa, FL, United States