Chihiro Iwasaki

Publications (6)6.58 Total impact

• Article: Effects of combination therapy with Renin-Angiotensin system inhibitors and eicosapentaenoic Acid on IgA nephropathy.

  Takahito Moriyama, Chihiro Iwasaki, Kayu Tanaka, Ayami Ochi, Ari Shimizu, Syunji Shiohira, Mitsuyo Itabashi, Takashi Takei, Keiko Uchida, Ken Tsuchiya, Kosaku Nitta
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  ABSTRACT: Objective The beneficial effects of renin-angiotensin-aldosterone system inhibitors (RASI) and the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) on IgA nephropathy (IgAN) have been reported. However, it is unknown whether these agents have any synergistic interactions. Methods We divided 38 IgAN patients into two groups: an EPA group (n=18) treated with RASI plus EPA and a DILAZEP group (n=20) treated with RASI plus dilazep dihydrochloride. We analyzed the clinical and histological background of each patient, any relevant clinical findings obtained one year after treatment and any factors significantly related to decreases in proteinuria. Results The clinical findings were largely similar between the groups, except for body mass index (24.9±4.5 in the EPA group vs. 21.4±2.1 in the DILAZEP group, p=0.0041) and total cholesterol (median: 206.0 vs. 177.5 mg/dL, p=0.0493). The histological findings, evaluated according to the Oxford classification, were also similar between the groups. At one year after treatment, the EPA group demonstrated a significantly decreased mean blood pressure (from 94.7±9.0 to 86.4±7.2 mmHg, p=0.0007) and a significantly decreased median level of proteinuria (from 0.80 to 0.41 g/g creatinine, p<0.001). In the DILAZEP group, the mean blood pressure significantly decreased (from 95.2±13.2 to 88.1±7.7 mmHg, p<0.001) without any significant decrease in the median level of proteinuria (from 0.88 to 0.60 g/g creatinine). According to a multivariate logistic analysis, EPA was found to be the only independent factor related to decreases in proteinuria (odds ratio = 5.073, 95% CI: 1.18-26.7, p=0.0285). Conclusion We conclude that EPA accelerates the effects of RASI and thus decreases the proteinuria observed in patients with IgAN.
  Internal Medicine 01/2013; 52(2):193-9. · 0.94 Impact Factor
• Article: Positive C1q staining associated with poor renal outcome in membranoproliferative glomerulonephritis.

  Takashi Takei, Mitsuyo Itabashi, Takahito Moriyama, Ari Shimizu, Yuki Tsuruta, Ayami Ochi, Kayu Nakayama, Chihiro Iwasaki, Keiko Uchida, Kosaku Nitta
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  ABSTRACT: BACKGROUND: Pathogenesis and clinical prognosis of membranoproliferative glomerulonephritis (MPGN) has not yet been established. METHODS: We conducted a retrospective study of 41 patients with MPGN (type I and III) and examined the renal survival. In addition, factors contributing to survival time were analyzed. RESULTS: Fourteen patients (34 %) were classified into the renal death group. Patients with nephrotic syndrome and positive C1q staining of glomerular deposits showed a particularly poor prognosis. Significantly higher frequency of nephrotic syndrome and higher urinary protein excretion were observed in the renal death group (p = 0.0002, p = 0.0002) than in the renal survival group. The intensity of C1q staining was positively correlated with the severity of the proteinuria (p = 0.004). Factors that influenced the survival time were positive C1q staining of glomerular deposits (p = 0.003), presence of nephrotic syndrome (p = 0.004), serum albumin (p = 0.02), and proteinuria (p = 0.04). CONCLUSIONS: C1q staining in glomerular deposits and nephrotic syndrome were important factors influencing the prognosis and outcome in MPGN patients. C1q deposition may play a key role in the pathogenesis of MPGN, as evidenced by numerous observations, such as induction of proteinuria.
  Clinical and Experimental Nephrology 07/2012; · 1.37 Impact Factor
• Article: Severity of nephrotic IgA nephropathy according to the Oxford classification.

  Takahito Moriyama, Kayu Nakayama, Chihiro Iwasaki, Ayami Ochi, Yuki Tsuruta, Mitsuyo Itabashi, Misao Tsukada, Takashi Takei, Keiko Uchida, Kosaku Nitta
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  ABSTRACT: IgA nephropathy with nephrotic syndrome (nephrotic IgAN) is a rare form of IgAN. Its prognosis and response to steroid therapy are still controversial because the differential diagnosis between nephrotic IgAN and minimal change nephrotic syndrome with IgA depositions is sometimes confused. In this retrospective cohort analysis, we accurately diagnosed 42 cases of nephrotic IgAN (4.4%) from 954 IgAN patients, according to the Oxford classification. We analyzed the clinical and histological data, prognosis, and response to steroid therapy. In nephrotic IgAN, mean estimated glomerular filtration rate (eGFR) was 51.1 ± 24.6 ml/min, proteinuria was 5.71 ± 2.56 g/day, and urinary red blood cells were 51.0 ± 37.8 high power field. Both active and chronic histological lesions were observed. Cumulative renal survival rate was significantly lower in nephrotic IgAN than in non-nephrotic IgAN (the control group consisted of 47 non-nephrotic IgAN patients diagnosed between 1995 and 1996) (log-rank test: P < 0.0001). The cases with steroid therapy significantly improved their prognosis, though their male-to-female ratio and blood pressure level measured at renal biopsy were significantly lower than in the cases without steroid therapy. Steroid therapy was particularly effective in cases with low-grade tubular atrophy and interstitial fibrosis (T-grade in Oxford classification). Without steroid therapy, lower eGFR and higher T-grade were independent risk factors for severe outcome by multivariate Cox regression. Nephrotic IgAN is a very severe form of IgAN, with renal dysfunction, massive hematuria, and active and chronic histopathological lesions. Renal outcome is severe; however, steroid therapy can improve prognosis in cases with higher eGFR and lower T-grade, according to the Oxford classification.
  International Urology and Nephrology 01/2012; 44(4):1177-84. · 1.47 Impact Factor
• Article: Rituximab treatment for adult patients with focal segmental glomerulosclerosis.

  Ayami Ochi, Takashi Takei, Kayu Nakayama, Chihiro Iwasaki, Daigo Kamei, Yuki Tsuruta, Ari Shimizu, Shunji Shiohira, Takahito Moriyama, Mitsuyo Itabashi, Toshio Mochizuki, Keiko Uchida, Ken Tsuchiya, Motoshi Hattori, Kosaku Nitta
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  ABSTRACT: We present two cases with steroid-resistant nephrotic syndrome (SRNS) and two cases with steroid-dependent nephrotic syndrome (SDNS) due to focal segmental glomerulonephritis (FSGS) who were treated with a single dose of rituximab (375 mg/m(2)). Although the two cases with SRNS showed no response, the two cases with SDNS achieved complete remission. The patients in whom the peripheral B-cell counts subsequently increased after the administration of rituximab demonstrated a relapse. Rituximab may be an effective treatment agent for SDNS with FSGS and the peripheral B-cell count may be a useful marker in such patients for preventing disease relapse.
  Internal Medicine 01/2012; 51(7):759-62. · 0.94 Impact Factor
• Article: Successful treatment with rituximab in a patient with TTP secondary to severe ANCA-associated vasculitis.

  Yukari Asamiya, Takahito Moriyama, Mari Takano, Chihiro Iwasaki, Kazuo Kimura, Yukako Ando, Akiko Aoki, Kan Kikuchi, Takashi Takei, Keiko Uchida, Kosaku Nitta
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  ABSTRACT: We report a case of thrombotic thrombocytopenic purpura (TTP) secondary to antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis treated by rituximab. TTP secondary to ANCA-associated vasculitis is very rare and has a high mortality rate. We employed rituximab and successfully treated TTP secondary to ANCA-associated vasculitis, because standard therapies, such as steroid therapy, intravenous pulse cyclophosphamide, and repeated plasma exchange (PE), did not suppress her disease activity. This is the first report to suggest that rituximab can achieve complete remission of TTP secondary to ANCA-associated vasculitis.
  Internal Medicine 01/2010; 49(15):1587-91. · 0.94 Impact Factor
• Article: Successful use of single-dose rituximab for the maintenance of remission in a patient with steroid-resistant nephrotic syndrome.

  Noritomo Kurosu, Hidekazu Sugiura, Chihiro Iwasaki, Yukari Asamiya, Chiari Kojima, Takahito Moriyama, Mitsuyo Itabashi, Misao Tsukada, Takashi Takei, Tetsuya Ogawa, Takumi Yoshida, Keiko Uchida, Ken Tsuchiya, Kosaku Nitta
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  ABSTRACT: We present the case of a 23-year-old man with steroid-resistant nephrotic syndrome due to minimal change disease who was treated with rituximab. The patient was resistant to conventional therapy. We therefore treated him with a single dose of rituximab (375 mg/m(2)). One month after the administration of rituximab, complete remission was achieved. However, six months later, the patient was administered a second dose of rituximab as the peripheral B cell counts began to recover. Thereafter, at present, that is, one year after the first rituximab administration, complete remission has been maintained. We conclude that rituximab may be an effective treatment agent for resistant nephrotic syndrome and the peripheral B cell count may be a useful marker in such patients for preventing disease relapse.
  Internal Medicine 01/2009; 48(21):1901-4. · 0.94 Impact Factor