研究者業績

平田 雄大

ヒラタ ユウタ  (Yuta Hirata)

基本情報

所属
自治医科大学 消化器一般移植外科 病院助教

研究者番号
40710257
J-GLOBAL ID
202001004316536486
researchmap会員ID
R000014493

外部リンク

経歴

 6

学歴

 1

主要な論文

 68
  • Shigeyoshi Yamanaga, Keita Shimata, Satoko Ohfuji, Mikiko Yoshikawa, Yoichiro Natori, Taizo Hibi, Kenji Yuzawa, Hiroto Egawa, Kohei Unagami, Hideki Ishida, Kazuya Omoto, Mureo Kasahara, Hajime Uchida, Seisuke Sakamoto, Kenta Futamura, Kenta Nishikawa, Ryoichi Imamura, Shigeaki Nakazawa, Etsuro Hatano, Takashi Ito, Yuki Masano, Morikuni Nishihira, Yuta Hirata, Yasunaru Sakuma, Yasuharu Onishi, Naoki Yokoyama, Shingo Yamamoto, Yusuke Yamada, Yasuhiro Ogura, Nobuhiko Kurata, Junji Uchida, Kazuya Kabei, Hitoshi Iwamoto, Chie Ikeda, Kazunobu Shinoda, Miki Yoshiike, Kiyohiko Hotta, Yuji Hidaka, Daiki Iwami, Yasuo Ishii, Manabu Kamiyama, Tomoharu Yoshizumi, Yukiko Kosai-Fujimoto, Takaaki Kobayashi, Kentaro Motoyama, Megumi Yamamoto, Toshihiro Asai, Masayuki Tasaki, Takashi Kenmochi, Taihei Ito, Kazuaki Tokodai, Atsushi Fujio, Yasumasa Tsukamoto, Takuya Watanabe, Nobuhisa Akamatsu, Sachi Yamashina, Daisuke Ishii, Kazuki Kitajima, Yasutoshi Yamada, Akihiko Mitsuke, Takashi Sakaguchi, Michio Nakamura, Yusuke Tomita, Yuki Nakamura, Tatsuro Ishimoto, Hideki Ohdan, Naoki Tanimine, Takuzo Fujiwara, Mitsuki Yanagihara, Shingo Hatakeyama, Manabu Takai, Kazuhiro Nose, Takashi Kikuchi, Yasunori Mori, Motoo Araki, Takanori Sekito, Shingo Nishimura, Tatsu Tanabe, Yuto Igarashi, Sumi Hidaka, Masaaki Watanabe, Yuichi Ariyoshi, Yasushi Hasegawa, Masato Kamiyama, Tatsuo Yoneda, Tomokazu Shimizu, Kouhei Nishikawa, Takumi Fukumoto, Kaoru Kuramitsu, Masashi Kato, Mitsuru Saito, Makoto Shinkai, Hidehito Usui, Masaaki Sato, Hidetoshi Eguchi, Hiroki Imamura, Shogo Kobayashi, Yuji Soejima, Atsuyoshi Mita, Takashi Kobayashi, Kenji Nakamura, Masayuki Ohtsuka, Shinichiro Nakada, Takahito Yagi, Kazuya Yasui, Naoto Matsuno, Chiharu Mizuno, Mikio Sugimoto, Nobufumi Ueda, Yoshinori Okada, Takashi Hirama, Shinichi Toyooka, Seichiro Sugimoto, Kei Matsubara, Toru Ikegami, Kenei Furukawa, Hiroyuki Nitta, Hirokatsu Katagiri, Toru Onita, Takeshi Shiraishi, Shugo Mizuno, Eisuke Amiya, Yasushi Shintani, Takashi Kanou, Soichiro Funaki, Yoshifumi Miura, Daisuke Nakajima, Taizen Urahashi, Goro Matsumiya, Michiko Watanabe, Yosuke Ebisu, Ryosuke Osawa, Minoru Ono, Hiroshi Sogawa, Harumi Gomi, Toyofumi Chen-Yoshikawa, Kazunari Yoshida, Naoko Ogawa
    American Journal of Transplantation 2024年3月  
  • 平田 雄大, 眞田 幸弘, 大西 康晴, 岡田 憲樹, 堀内 俊男, 大豆生田 尚彦, 佐久間 康成, 佐田 尚宏
    日本小児外科学会雑誌 59(7) 1058-1063 2023年12月  
    腸管重積型逆流防止弁付加手術を行った胆道閉鎖症(BA)において,挙上空腸狭窄が難治性胆管炎の契機となり,生体肝移植(LDLT)を施行した2例を報告する.【症例1】15歳女児.生後1ヵ月時にBAに対して肝門部空腸吻合術を施行したが,胆汁排泄不良で生後2ヵ月時に逆流防止弁付き再吻合術を施行した.術後15年時に挙上空腸狭窄による難治性胆管炎に対してイレウス管を留置したが,肝内胆管数珠状拡張と黄疸は改善せず,LDLTを施行した.【症例2】26歳男性.生後4ヵ月時にBAに対して逆流防止弁付き肝門部空腸吻合術を施行した.術後25年時に黄疸を伴う胆管炎が出現したため,挙上空腸狭窄に対してENBDチューブを留置したが,胆管炎は改善せず,LDLTを施行した.逆流防止弁は長期BAにおいて挙上空腸狭窄による難治性胆管炎の原因になることがある.(著者抄録)
  • 平田雄大、眞田幸弘、大西康晴、岡田憲樹、堀内俊男、佐久間康成
    肝臓 63(9) 538-540 2022年12月  査読有り筆頭著者
  • Noriki Okada, Yuta Kawahara, Yukihiro Sanada, Yuta Hirata, Shinya Otomo, Hitomi Niijima, Akira Tanaka, Akira Morimoto, Alan K Lefor, Taizen Urahashi, Yoshikazu Yasuda, Koichi Mizuta, Yasunaru Sakuma, Naohiro Sata
    American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons 21(9) 3184-3189 2021年4月1日  
    Maternal T cells from perinatal transplacental passage have been identified in up to 40% of patients with severe combined immunodeficiency (SCID). Although engrafted maternal T cells sometimes injure newborn tissue, liver failure due to maternal T cells has not been reported. We rescued a boy with X-linked SCID who developed liver failure due to engrafted maternal T cell invasion following living donor liver transplantation (LDLT) following unrelated umbilical cord blood transplantation (UCBT). After developing respiratory failure 3 weeks postpartum, he was diagnosed with X-linked SCID. Pathological findings showed maternal T cells engrafted in his liver and hepatic fibrosis gradually progressed. He underwent UCBT at 6 months, but hepatic function did not recover and liver failure progressed. Therefore, he underwent LDLT using an S2 monosegment graft at age 1.3 years. The patient had a leak at the Roux-en-Y anastomosis, which was repaired. Despite occasional episodes of pneumonia and otitis media, he is generally doing well 6 years after LDLT with continued immunosuppression agents. In conclusion, the combination of hematopoietic stem cell transplantation (HSCT) and liver transplantation may be efficacious, and HSCT should precede liver transplantation for children with X-linked SCID and liver failure.
  • Yuta Hirata, Yukihiro Sanada, Takahiko Omameuda, Takumi Katano, Go Miyahara, Naoya Yamada, Noriki Okada, Yasuharu Onishi, Yasunaru Sakuma, Naohiro Sata
    Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation 18(5) 612-617 2020年10月  査読有り筆頭著者
    OBJECTIVES: Predicting the risk of posthepatectomy liver failure is important when performing extended hepatectomy. However, there is no established method to evaluate liver function and improve preoperative liver function in pediatric patients. MATERIALS AND METHODS: We show the clinical features of pediatric patients who underwent living donor liver transplant for posthepatectomy liver failure in hepatoblastoma. The subjects were 4 patients with hepatoblastoma who were classified as Pretreatment Extent of Disease III, 2 of whom had distal metastasis (chest wall and lung). RESULTS: Hepatic right trisegmentectomy was performed in 3 patients and extended left hepatectomy in 1 patient. The median alpha-fetoprotein level at the diagnosis of hepatoblastoma was 986300 ng/mL (range, 22500-2726350 ng/mL), and the median alpha-fetoprotein level before hepatectomy was 8489 ng/mL (range, 23-22500 ng/mL). The remnant liver volume after hepatectomy was 33.3% (range, 20% to 34.9%). Four patients had cholangitis after hepatectomy and progressed to posthepatectomy liver failure. The peak serum total bilirubin after hepatectomy was 11.4 mg/dL (range, 8.7-14.6 mg/dL). Living donor liver transplant was performed for these 4 patients with posthepatectomy liver failure, and they did not have a recurrence. CONCLUSIONS: When the predictive remnant liver volume by computed tomography-volumetry before extended hepatectomy for patients with hepatoblastoma is less than 40%, the possibility of posthepatectomy liver failure should be recognized.
  • Yuta Hirata, Yukihiro Sanada, Takahiko Omameuda, Takumi Katano, Go Miyahara, Naoya Yamada, Noriki Okada, Yasuharu Onishi, Yasunaru Sakuma, Naohiro Sata
    Surgical case reports 6(1) 159-159 2020年7月3日  査読有り筆頭著者
    BACKGROUND: There have been no reports on the effectiveness of the administration of antithrombin III (AT III) for post-transplant portal vein thrombosis (PVT). We herein report a case of post-transplant PVT that was resolved by AT III treatment after living donor liver transplantation (LDLT). CASE PRESENTATION: The patient was a 57-year-old man who had been diagnosed with decompensate liver cirrhosis by hepatitis C virus infection. He presented with repeated hepatic coma and refractory ascites. Computed tomography (CT) revealed PVT of Yerdel classification grade II before LDLT. He underwent ABO-identical LDLT using a right lobe graft. A liver function test revealed elevated liver enzyme levels on post-operative day (POD) 14. The CT examination on POD 15 revealed PVT in the left side of the main portal vein at the side of left gastric vein ligation. AT III treatment from POD 15 to POD 24 was performed. Magnetic resonance imaging revealed that the PVT had decreased 10% on POD 27. Furthermore, AT III treatment from POD 28 to POD 32 was performed. The CT examination demonstrated the disappearance of PVT on POD 69 and thereafter, he had no recurrence of PVT on 10 post-operative month (POM). CONCLUSIONS: The present case suggests that the administration of AT III is safe and suitable for the treatment of post-transplant PVT.
  • Yukihiro Sanada, Takumi Katano, Yuta Hirata, Naoya Yamada, Noriki Okada, Yoshiyuki Ihara, Koichi Mizuta
    Transplantation 103(9) 1863-1870 2019年9月  
    BACKGROUND: We present retrospective analysis of our 15-year experience with pediatric living donor liver transplantation, focusing on the risk factors, treatments, and long-term prognosis for posttransplant biliary complications (BCs). METHODS: Between May 2001 and December 2017, 290 living donor liver transplantations were performed. The median age was 1.4 years old. The median observation period was 8.4 years. Biliary strictures were classified as anastomotic stricture (AS) or non-AS (NAS). RESULTS: Overall incidence of biliary complications was 18.6%, including AS in 46 cases, NAS in 6, and other classifications in 2. The mean period to diagnosis of the AS was 641 ± 810 postoperative days. The multivariate analysis showed that hepaticojejunostomy without external stent was an independent risk factor for AS (P = 0.011). The first treatments for AS were percutaneous transhepatic biliary drainage (PTBD) in 25 cases, double-balloon enteroscopy (DBE) in 19, and surgical reanastomosis in 2. The success and recurrence rates of PTBD treatments were 90.9% and 22.7%, respectively. The success and recurrence rates of endoscopic interventions under DBE were 93.6% and 75.3%, respectively. The 15-year graft survival rates in patients with and without AS were 95.7% and 89.1%, respectively (P = 0.255), but 2 patients with cholangitis due to multiple NAS underwent retransplantation. CONCLUSIONS: Posttransplant AS can be prevented by hepaticojejunostomy using external stent, and the long-term prognosis is good with early treatments using DBE or PTBD. However, the prognosis of multiple NAS is poor.
  • Noriki Okada, Yukihiro Sanada, Yasuharu Onishi, Taizen Urahashi, Yoshiyuki Ihara, Naoya Yamada, Yuta Hirata, Takumi Katano, Toshimi Imai, Kentaro Ushijima, Keiko Ogaki, Shinya Otomo, Koichi Mizuta
    Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society 25(7) 1066-1073 2019年7月  
    Early relaparotomy of adult recipients after living donor liver transplantation (LDLT) is significantly associated with poor prognosis. However, there are few reports focusing on pediatric recipients after LDLT. The aim of this study is to clarify the causes and outcomes of early relaparotomy after pediatric LDLT. A total of 265 pediatric recipients (272 LDLTs) transplanted from May 2001 to October 2015 were retrospectively analyzed. Early relaparotomy was defined as surgical intervention performed within 3 months after LDLT. Early relaparotomy was performed 49 times for 33 recipients (12.5%). The recipient and graft survival rates in the early relaparotomy group were significantly lower than those in the nonearly relaparotomy group, respectively (75.0% and 63.6% versus 96.6% and 95.8%; both P < 0.001). Left lateral segment grafts were used significantly more frequently in the nonrelaparotomy group (P = 0.01). According to the multivariate analysis, the preoperative Pediatric End-Stage Liver Disease (PELD)/Model for End-Stage Liver Disease (MELD) score of the early relaparotomy group was significantly higher than that of the nonearly relaparotomy group (13.7 versus 6.3; P = 0.04). According to the receiver operating characteristic curve, the preoperative PELD/MELD score cutoff point was 17.2. Early relaparotomy due to infectious causes led to significantly poorer graft survival than that due to noninfectious causes (P = 0.04). In conclusion, the recipient and graft survival rates of the early relaparotomy group were significantly lower than those of the nonearly relaparotomy group. A high preoperative PELD/MELD score was a risk factor for early relaparotomy. In particular, early relaparotomy due to infection showed a poor prognosis.
  • Yukihiro Sanada, Shuji Hishikawa, Takumi Katano, Yuta Hirata, Naoya Yamada, Noriki Okada, Koichi Mizuta
    Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society 25(3) 510-514 2019年3月  
  • Naoya Yamada, Takumi Katano, Yuta Hirata, Noriki Okada, Yukihiro Sanada, Yoshiyuki Ihara, Taizen Urahashi, Kentaro Ushijima, Tadayoshi Karasawa, Masafumi Takahashi, Koichi Mizuta
    Journal of gastroenterology and hepatology 34(2) 418-424 2019年2月  
    BACKGROUND AND AIM: Serum Mac-2 binding protein glycosylation isomer (M2BPGi) is a novel fibrosis marker for various chronic liver diseases. We investigated the ability of M2BPGi to predict liver fibrosis in liver transplant (LT) recipients. METHODS: A total of 116 liver biopsies were performed in 113 LT recipients. The serum level of M2BPGi was also measured on the same day. The median age at LT and liver biopsy was 1.1 and 11.8 years, respectively. Serum M2BPGi levels and liver fibrosis status using METAVIR fibrosis score were compared. Immunohistological evaluation by anti-α-smooth-muscle actin (αSMA) was performed, and the relationship between αSMA positive rate and serum M2BPGi levels was investigated. RESULTS: The median M2BPGi level was 0.78 (range, 0.22-9.50), and 65, 29, 16, 5, and 1 patient(s) had METAVIR fibrosis scores of F0, F1, F2, F3, and F4, respectively. In patients with F0 fibrosis, median M2BPGi level was 0.69 and was significantly lower than in patients with F1 (median 0.99, P < 0.01), F2 (median 1.00, P = 0.01), and F3 fibrosis (median 1.53, P < 0.01). Area-under-the-curve analysis of the ability of M2BPGi level to predict liver fibrosis grade were > F1: 0.716, > F2: 0.720, and > F3: 0.900. Three patients with acute cellular rejection showed high levels of M2BPGi, which decreased after the treatment. A positive correlation existed between M2BPGi levels and αSMA positive rate (r2  = 0.715, P < 0.01). CONCLUSION: Mac-2 binding protein glycosylation isomer is a novel liver fibrosis marker in LT recipients and is also increased in patients with acute liver injuries, especially acute cellular rejection, even when fibrosis is absent.
  • Yukihiro Sanada, Tomonori Yano, Taizen Urahashi, Yoshiyuki Ihara, Noriki Okada, Naoya Yamada, Yuta Hirata, Takumi Katano, Hironori Yamamoto, Koichi Mizuta
    Liver transplantation : official publication of the American Association for the Study of Liver Diseases and the International Liver Transplantation Society 24(3) 436-439 2018年3月  
  • Hirata, Y. Sanada, Y. Urahashi, T. Ihara, Y. Yamada, N. Okada, N. Katano, T. Otomo, S. Ushijima, K. Mizuta, K
    Transplant Proc 60-65 2018年1月  査読有り筆頭著者
  • Naoya Yamada, Yukihiro Sanada, Masahisa Tashiro, Yuta Hirata, Noriki Okada, Yoshiyuki Ihara, Taizen Urahashi, Koichi Mizuta
    Journal of gastroenterology 52(2) 245-252 2017年2月  
    BACKGROUND AND AIM: Mac-2 Binding Protein Glycosylation Isomer (M2BPGi) is a novel fibrosis marker. We examined the ability of M2BPGi to predict liver fibrosis in patients with biliary atresia. METHODS: Sixty-four patients who underwent living donor liver transplantation (LDLT) were included [median age, 1.1 years (range 0.4-16.0), male 16 patients (25.0 %)]. We examined M2BPGi levels in serum obtained the day before LDLT, and we compared the value of the preoperative M2BPGi levels with the histological evaluation of fibrosis using the METAVIR fibrosis score. Subsequently, we assessed the ability of M2BPGi levels to predict fibrosis. RESULTS: The median M2BPGi level in patients with BA was 6.02 (range, 0.36-20.0), and 0, 1, 1, 11, and 51 patients had METAVIR fibrosis scores of F0, F1, F2, F3, and F4, respectively. In patients with F4 fibrosis, the median M2BPGi level was 6.88 (quartile; 5.235, 12.10), significantly higher than that in patients with F3 fibrosis who had a median level of 2.42 (quartile; 1.93, 2.895, p < 0.01). Area under the curve analysis for the ability of M2BPGi level to predict grade fibrosis was 0.917, with a specificity and sensitivity of 0.923 and 0.941, respectively. In comparison with other fibrosis markers such as hyaluronic acid, procollagen-III-peptide, type IV collagen 7 s, and aspartate aminotransferase platelet ratio index, M2BPGi showed the strongest ability to predict grade F4 fibrosis. CONCLUSION: M2BPGi is a novel fibrosis marker for evaluating the status of the liver in patients with BA, especially when predicting grade F4 fibrosis.
  • Naoya Yamada, Yukihiro Sanada, Takumi Katano, Masahisa Tashiro, Yuta Hirata, Noriki Okada, Yoshiyuki Ihara, Atsushi Miki, Hideki Sasanuma, Taizen Urahashi, Yasunaru Sakuma, Koichi Mizuta
    World journal of gastroenterology 22(44) 9865-9870 2016年11月28日  
    This is the first report of living donor liver transplantation (LDLT) for congenital hepatic fibrosis (CHF) using a mother's graft with von Meyenburg complex. A 6-year-old girl with CHF, who suffered from recurrent gastrointestinal bleeding, was referred to our hospital for liver transplantation. Her 38-year-old mother was investigated as a living donor and multiple biliary hamartoma were seen on her computed tomography and magnetic resonance imaging scan. The mother's liver function tests were normal and she did not have any organ abnormality, including polycystic kidney disease. LDLT using the left lateral segment (LLS) graft from the donor was performed. The donor LLS graft weighed 250 g; the graft recipient weight ratio was 1.19%. The operation and post-operative course of the donor were uneventful and she was discharged on post-operative day (POD) 8. The graft liver function was good, and the recipient was discharged on POD 31. LDLT using a graft with von Meyenburg complex is safe and useful. Long-term follow-up is needed with respect to graft liver function and screening malignant tumors.
  • 平田 雄大, 井原 欣幸, 岡田 憲樹, 眞田 幸弘, 水田 耕一
    日本小児外科学会雑誌 52(6) 1236-1240 2016年10月  査読有り筆頭著者
  • Yukihiro Sanada, Yasunaru Sakuma, Hideki Sasanuma, Atsushi Miki, Takumi Katano, Yuta Hirata, Noriki Okada, Naoya Yamada, Yoshiyuki Ihara, Taizen Urahashi, Naohiro Sata, Yoshikazu Yasuda, Koichi Mizuta
    World journal of gastroenterology 22(34) 7851-6 2016年9月14日  
    Utilizing the opened round ligament as venous grafts during liver transplantation is useful but controversial, and there are no pathological analyses of this procedure. Herein, we describe the first reported case of a pathological analysis of an opened round ligament used as a venous patch graft in a living donor liver transplantation (LDLT). A 13-year-old female patient with biliary atresia underwent LDLT using a posterior segment graft from her mother. The graft had two hepatic veins (HVs), which included the right HV (RHV; 15 mm) and the inferior RHV (IRHV; 20 mm). The graft RHV and IRHV were formed into a single orifice using the donor's opened round ligament (60 mm × 20 mm) as a patch graft during bench surgery; it was then anastomosed end-to-side with the recipient inferior vena cava. The recipient had no post-transplant complications involving the HVs, but she died of septic shock with persistent cholangitis and jaundice 86 d after LDLT. The HV anastomotic site had no stenosis or thrombus on autopsy. On pathology, there was adequate patency and continuity between the recipient's HV and the donor's opened round ligament. In addition, the stains for CD31 and CD34 on the inner membrane of the opened round ligament were positive. Hepatic venous reconstruction using the opened round ligament as a venous patch graft is effective in LDLT, as observed on pathology.
  • Y Hirata, Y. Sanada a, T. Urahashi a, Y. Ihara a, N. Yamada a, N. Okada a, M. Tashiro a, T. Katano a, S. Otomo b, K. Ushijima c, K. Mizuta
    Transplant Proc 1105-1109 2016年5月  査読有り筆頭著者
  • Sanada Y, Urahashi T, Ihara Y, Wakiya T, Okada N, Yamada N, Hirata Y, Mizuta K
    Hepato-gastroenterology 61(133) 1368-1373 2014年7月  査読有り
  • Yukihiro Sanada, Taizen Urahashi, Yoshiyuki Ihara, Taiichi Wakiya, Noriki Okada, Naoya Yamada, Yuta Hirata, Koichi Mizuta
    HEPATO-GASTROENTEROLOGY 61(133) 1368-1373 2014年7月  査読有り
    Background/Aims: (beta-D glucan in the portal vein blood is processed by the hepatic reticuloendothelial system, and therefore, it is possible that the beta-D glucan kinetics of the peripheral vein blood may be useful as a biological index. In this study, the beta-D glucan levels in the peripheral and portal vein blood during liver transplantation were measured in order to study the clinical significance of the molecule. Methodology: The subjects comprised 20 patients who underwent living donor liver transplantation. In the perioperative period, the beta-D glucan levels were measured before liver transplantation, during surgical procedure, then on postoperative days 5, 14, and 21. Results: The portal vein blood showed a significantly higher level beta-D glucan than the peripheral blood (p&lt;0.001). A significant difference of beta-D glucan levels was observed between the pre-liver transplantation and postoperative days 5 (p=0.048). There was a significant positive correlation between the preoperative beta-D glucan level and the period of postoperative hospitalization (p&lt;0.001). The patients with fungal infections (35.0%) had a significantly longer period of hospitalization.(p=0.019). Conclusions: The beta-D glucan kinetics accurately reflects the liver function and fungal infections. The beta-D glucan level before liver transplantation can be used to predict the period of hospitalization.
  • Yukihiro Sanada, Koshi Matsumoto, Taizen Urahashi, Yoshiyuki Ihara, Taiichi Wakiya, Noriki Okada, Naoya Yamada, Yuta Hirata, Koichi Mizuta
    World journal of gastroenterology 20(21) 6638-50 2014年6月7日  
    AIM: To assessed the clinical significance of protocol liver biopsy (PLB) in pediatric liver transplantation (LT). METHODS: Between July 2008 and August 2012, 89 and 55 PLBs were performed in pediatric patients at two and five years after LT, respectively. We assessed the histopathological findings using the Metavir scoring system, including activity (A) and fibrosis (F), and we identified factors associated with scores of ≥ A1 and ≥ F1. Our results clarified the timing and effectiveness of PLB. RESULTS: The incidences of scores of ≥ A1 and ≥ F1 were 24.7% and 24.7%, respectively, at two years after LT and 42.3% and 34.5%, respectively, at five years. Independent risk factors in a multivariate analysis of a score of ≥ A1 at two years included ≥ 2 h of cold ischemic time, no acute cellular rejection and an alanine amino transaminase (ALT) level of ≥ 20 IU/L (P = 0.028, P = 0.033 and P = 0.012, respectively); however, no risk factors were identified for a score of ≥ F1. Furthermore, no independent risk factors associated with scores of ≥ A1 and ≥ F1 at five years were identified using multivariate analysis. A ROC curve analysis of ALT at two years for a score of ≥ A1 demonstrated the recommended cutoff value for diagnosing ≥ A1 histology to be 20 IU/L. The incidence of scores of ≥ A2 or ≥ F2 at two years after LT was 3.4% (three cases), and all patients had an absolute score of ≥ A2. In contrast to that observed for PLBs at five years after LT, the incidence of scores of ≥ A2 or ≥ F2 was 20.0% (11 cases), and all patients had an absolute score of ≥ F2. In all cases, the dose of immunosuppressants was increased after the PLB, and all ten patients who underwent a follow-up liver biopsy improved to scores of ≤ A1 or F1. CONCLUSION: PLB at two years after LT is an unnecessary examination, because the serum ALT level reflects portal inflammation. In addition, immunosuppressive therapy should be modulated to maintain the ALT concentration at a level less than 20 IU/L. PLB at five years is an excellent examination for the detection of early reversible graft fibrosis because no serum markers reflect this finding.

MISC

 16

書籍等出版物

 2

講演・口頭発表等

 43

共同研究・競争的資金等の研究課題

 2