岡田 憲樹

The liver and pancreas work together to recover homeostasis after hepatectomy. This study aimed to investigate the effect of liver resection volume on the pancreas. We collected clinical data from 336 living liver donors. They were categorized into left lateral sectionectomy (LLS), left lobectomy, and right lobectomy (RL) groups. Serum pancreatic enzymes were compared among the groups. Serum amylase values peaked on postoperative day (POD) 1. Though they quickly returned to preoperative levels on POD 3, 46% of cases showed abnormal values on POD 7 in the RL group. Serum lipase levels were highest at POD 7. Lipase values increased 5.7-fold on POD 7 in the RL group and 82% of cases showed abnormal values. The RL group's lipase was twice that of the LLS group. A negative correlation existed between the remnant liver volume and amylase (r = - 0.326)/lipase (r = - 0.367) on POD 7. Furthermore, a significant correlation was observed between POD 7 serum bilirubin and amylase (r = 0.379)/lipase (r = 0.381) levels, indicating cooccurrence with liver and pancreatic strain. Pancreatic strain due to hepatectomy occurs in a resection/remnant liver volume-dependent manner. It would be beneficial to closely monitor pancreatic function in patients undergoing a major hepatectomy.

BACKGROUND: COACH syndrome is a rare autosomal recessive genetic disease characterized by liver fibrosis, which leads to severe complications related to portal hypertension. However, only a few patients with COACH syndrome undergoing liver transplantation (LT) have been reported. MATERIALS AND METHODS: We herein report the outcomes of four children who underwent LT for COACH syndrome at our institute and review three previously reported cases to elucidate the role of LT in COACH syndrome. RESULTS: All four patients in our institute were female, and three received living donors LT. All patients were diagnosed with COACH syndrome by genetic testing. LT was performed in these patients at 3, 7, 9, and 14 years old. The indication for LT was varices related to portal hypertension in all patients. One showed an intrapulmonary shunt. Blood tests revealed renal impairment due to nephronophthisis in three patients, and one developed renal insufficiency after LT. The liver function was maintained in all patients. A literature review revealed detailed information for three more patients. The indication for LT in these three cases was portal hypertension, such as bleeding from esophageal varices. One patient had chronic renal failure on hemodialysis at LT and underwent combined liver and kidney transplantation. Of these three previous patients, one died from hepatic failure due to de novo HCV infection 3 years after LT. CONCLUSIONS: LT should be considered an effective treatment for COACH syndrome in patients with severe portal hypertension. However, a detailed follow-up of the renal function is necessary.

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)

自己肝温存胆道閉鎖症の長期経過観察中に肝内胆管癌を認めた1例を報告する.25歳男性.日齢78にIII-a1-vの胆道閉鎖症に対して逆流防止弁付き肝門部空腸吻合術を施行した.21歳時に超音波検査で肝右葉に嚢状肝内胆管拡張を認め,bile lakeとして経過観察した.25歳時に黄疸を伴う胆管炎と肝膿瘍を疑う病変を認め,小腸内視鏡を施行し,逆流防止弁の狭窄解除を行ったが,肝門部空腸吻合部に到達できなかった.難治性胆管炎にて肝移植を考慮され,当科紹介となった.当科受診時のCA19-9が7,092U/mlと高値であり,肝右葉の腫瘍性病変に対して生検を施行し,肝内胆管癌stage IVB(腹膜播種)と診断した.門脈浸潤に対して経皮経肝的ステント留置を行い,化学療法を施行したが,化学療法開始11ヵ月時に十二指腸浸潤の消化管出血で死亡した.胆道閉鎖症の長期管理に悪性腫瘍のスクリーニングは必須である.(著者抄録)

対象は肝移植後外来フォロー中の2021年12月～2022年5月にCOVID-19陽性となった小児18例(男児8例、女児10例)で肝移植時年齢中央値0歳、感染時年齢中央値12歳、肝移植後感染時期は移植後131ヵ月であった。臨床症状は咳嗽12例(66.7%)、発熱10例(55.6%)、鼻汁8例(44.4%)、咽頭痛6例(33.3%)の順であり、重症度は全例軽症であった。COVID-19の移植医療における基本指針の第5版のガイドラインに基づき、ミコフェノール酸モフェチル(MMF)内服中の5例中2例にMMFを半量に減量する指示を行ったが、抗ウイルス薬を投与した症例はなく、全例後遺症なく治癒した。

BACKGROUND: Repeat liver transplantation (LT) for patients with the liver graft failure who underwent metallic stent placement in the previous graft hepatic vein (HV) for HV complications can be very difficult. We retrospectively reviewed the safer surgical procedures during repeat LT for patients with a metallic stent in the graft HV. CASE REPORTS: Patient 1 with biliary atresia who was treated with metallic stent placement for HV stenosis underwent a third LT form a deceased donor at the age 17 years. Patient 2 with ornithine transcarbamylase deficiency who was treated with metallic stent placement for refractory HV stenosis underwent a second LT form a deceased donor at age 9 years. In both patients, transection of the previous graft HV through an intraabdominal approach was difficult during repeat LT, and a supradiaphragmatic inferior vena cava (IVC) approach was introduced. Using a midline incision of the diaphragm, the pericardium was incised and the supradiaphragmatic IVC was encircled. After clamping the supradiaphragmatic IVC, graft hepatectomy was performed. The metallic stent was successfully removed breaking, and HV reconstruction was performed on the suprahepatic IVC. Both patients did well without serious HV complications after repeat LT. CONCLUSIONS: The surgical technique for the supradiaphragmatic IVC approach is useful to decrease the risk of fatal operative complications during repeat LT for patients with a metallic stent in the graft HV.

肝移植領域でのエベロリムス(EVR)の使用経験例は少ない。またEVRは移植臓器である肝臓で代謝されることに加えて、初期投与量設定に用いる指標がないため速やかに目標血中濃度に到達させるのが難しい現状がある。今回、タクロリムス(Tac)の薬物動態に基づいたEVRの初期投与量設計の可能性を見出すため、自治医科大学附属病院におけるEARとTacの薬物動態の相関関係を検討した。方法として、EVRとTacの血中濃度(ng/mL)を1日投与量(mg/day)で除したC/D比を算出し、相関関係を後方視的に検討した。結果は患者間でEVRの1日投与量と血中濃度の相関関係はなく(r=0.3615、p=0.169)、EARとTacのC/D比に正の相関関係が得られた(r=0.7472、p<0.001)。肝移植症例におけるTacとEVRの薬物動態には相関関係があるため、今後、EVR投与量設計の参考になると思われた。(著者抄録)

肝移植後胆道合併症は依然として発症率が高く、予後に影響する重要な合併症である。胆道合併症は胆管狭窄、胆汁瘻に大別されるが、肝内結石はまれであり、とくに小児肝移植後肝内結石の診断・治療は確立されていない。小児肝移植症例の胆道再建は胆管空腸吻合がほとんどであるため、胆道合併症に対する治療は経皮経肝的胆道ドレナージ(PTBD)下カテーテル治療か外科的治療に限られていた。近年、ダブルバルーン小腸内視鏡(DBE)の改良とデバイスの進歩により、小児肝移植後胆道合併症においてもDBE下カテーテル治療が可能になってきている。低侵襲治療であるDBE下治療により、小児肝移植後肝内結石に対しても早期発見治療が可能となり、今後長期予後の向上が期待できる。(著者抄録)

BACKGROUND: Sinusoidal obstruction syndrome (SOS) after liver transplantation (LT) is a rare and potentially lethal complication. We retrospectively reviewed the outcomes of patients with post-transplant SOS. METHODS: Between May 2001 and December 2019, of 332 patients who underwent LT, 5 (1.5%) developed SOS. The median age at LT was 1.7 years (range 0.1-66.5). SOS was histopathologically diagnosed and classified as early-onset (<1 month) or late-onset. RESULTS: The median time to diagnosis of SOS was one month after LT. All patients developed acute cellular rejection before SOS, and the cause of SOS was acute cellular rejection in four patients and unknown in one. The treatment of SOS included conversion to tacrolimus from cyclosporine, intrahepatic hepatic vein stent placement, strengthening of immunosuppression, and plasma exchange. The 5-year graft survival rates in patients with and without SOS were 53.0% and 92.5%, respectively (p < 0.001). Of three patients with early-onset SOS, two patients improved and are doing well, and one patient died of graft failure four months after LT. CONCLUSIONS: The cause and treatment of post-transplant SOS are not yet defined. The poor outcomes in patients with early-onset SOS may be improved by strengthening of immunosuppression. Patients with late-onset SOS are ultimately treated by repeat LT.

BACKGROUND: There is no consensus about long-term outcomes in patients with biliary atresia. We retrospectively reviewed the long-term outcomes in pediatric patients who underwent living donor liver transplantation for biliary atresia. METHODS: Between May 2001 and December 2020, 221 (73%) of 302 pediatric patients who underwent living donor liver transplantation had biliary atresia. The median age at living donor liver transplantation was 1.2 (range 0.2-16.5) years, and follow-up was 10.3 ± 5.5 years. RESULTS: The 10-year graft survival rates in patients with and without biliary atresia were 94% and 89%, respectively (P = .019). The 10-year graft survival was significantly poorer in patients ≥12 years of age (84%) versus those <12 years of age at living donor liver transplantation (0-2 years: 95%; 2-12 years: 96%) (P = .016). The causes of graft failure in patients with biliary atresia included late-onset refractory rejection (n = 6), bowel perforation (n = 2), and acute encephalitis (n = 2), as well as cerebral hemorrhage, hepatic vein thrombosis, and sepsis (n = 1 for all). All 7 patients with graft failure due to refractory rejection and hepatic vein thrombosis underwent repeated liver transplantation and are alive in 2021. The rates of post-transplant portal vein complications and early-onset acute cellular rejection in patients with biliary atresia were higher than in those without biliary atresia (P = .042 and P = .022, respectively). In 2021, of 60 adolescents with biliary atresia, 14 (23%) reported medication nonadherence. The rate of liver dysfunction due to late-onset acute cellular rejection and graft failure due to late-onset refractory rejection in patients with nonadherence was higher than in patients with satisfactory adherence (P = .009). CONCLUSION: The long-term prognosis after living donor liver transplantation in pediatric patients with biliary atresia is quite good. However, long-term support to enhance medication adherence is required in adolescents with biliary atresia.

There is little information about the outcomes of pediatric patients with hepatolithiasis after living donor liver transplantation (LDLT). We retrospectively reviewed hepatolithiasis after pediatric LDLT. Between May 2001 and December 2020, 310 pediatric patients underwent LDLT with hepaticojejunostomy. Treatment for 57 patients (18%) with post-transplant biliary strictures included interventions through double-balloon enteroscopy (DBE) in 100 times, percutaneous transhepatic biliary drainage (PTBD) in 43, surgical re-anastomosis in 4, and repeat liver transplantation in 3. The median age and interval at treatment were 12.3 years old and 2.4 years after LDLT, respectively. At the time of treatments, 23 patients (7%) had developed hepatolithiasis of whom 12 (52%) were diagnosed by computed tomography before treatment. Treatment for hepatolithiasis included intervention through DBE performed 34 times and PTBD 6, including lithotripsy by catheter 23 times, removal of plastic stent in 8, natural exclusion after balloon dilatation in 7, and impossibility of removal in 2. The incidence of recurrent hepatolithiasis was 30%. The 15-years graft survival rates in patients with and without hepatolithiasis were 91% and 89%, respectively (p = 0.860). Although hepatolithiasis after pediatric LDLT can be treated using interventions through DBE or PTBD and its long-term prognosis is good, the recurrence rate is somewhat high.

BACKGROUND There is no consensus about the long-term prognosis of pediatric patients with a variety of rare liver diseases but with inherited metabolic diseases (IMDs). We retrospectively reviewed the developmental outcomes of patients with IMDs undergoing living donor liver transplantation (LDLT). MATERIAL AND METHODS Between May 2001 and December 2020, of 314 pediatric patients who underwent LDLT, 44 (14%) had IMDs. The median age at LDLT was 3.0 years old (range 0-15.0 years). Associations between the post-transplant complications and graft survival rate in patients with IMDs and biliary atresia (BA) were calculated. We evaluated the safety of LDLT from heterozygous carrier donors, the prognosis of patients with IMDs who have metabolic defects expressed in other organs, and developmental outcomes of patients with IMDs. RESULTS The 10-year graft survival rates in patients with IMDs and BA were 87% and 94%, respectively (P=0.041), and the causes of graft failure included pneumocystis pneumonia, acute lung failure, hemophagocytic syndrome, hepatic vein thrombosis, portal vein thrombosis, and sepsis. The rate of post-transplant cytomegalovirus viremia in patients with IMDs was higher than that of patients with BA (P=0.039). Of 39 patients with IMDs, 15 patients (38%) had severe motor and intellectual disabilities in 4 patients, intellectual developmental disorders including epilepsy in 2, and attention-deficit hyperactivity disorder in 2. Of 28 patients with IMDs, 13 (46%) needed special education. CONCLUSIONS The long-term outcomes of LDLT in patients with IMDs are good. However, further long-term social and educational follow-up regarding intellectual developmental disorders is needed.

Patients with hepatitis-associated aplastic anemia (HAA) who undergo living-donor liver transplantation (LDLT) have a poor prognosis with infections and bleeding complications. Rapid recovery of blood cells is critical for preventing these complications and improving the outcome. Immunosuppressive therapy (IST) combined with thrombopoietin receptor agonists is considered effective for aplastic anemia. However, there are no data on the benefits of adding thrombopoietin receptor agonists to IST for HAA. We present the case of a child with severe HAA who underwent LDLT, and who achieved rapid blood cell recovery with IST combined with romiplostim, a thrombopoietin receptor agonist. In addition, despite having undergone LDLT, the patient had no adverse events such as serious liver dysfunction or thrombosis. This case suggests that IST combined with thrombopoietin receptor agonists may be a promising treatment option for HAA patients undergoing LDLT.

BACKGROUND: Complications associated with ultrasonographically guided percutaneous transhepatic liver biopsy (PTLB) after liver transplantation (LT) have been rarely reported, and there is no consensus about its safety. We retrospectively reviewed the safety and outcomes of PTLB after pediatric LT. METHODS: Between January 2008 and December 2019, 8/1122 (0.71%) pediatric patients who underwent ultrasonographically guided PTLB after LT developed complications. The median age at PTLB was 7.8 years (range 0.1-17.9). Grafts included left lobe/left lateral segment in 1050 patients and others in 72. PTLB was performed using local anesthesia±sedation in 1028 patients and general anesthesia in 94. RESULTS: Complications after PTLB included acute cholangitis in 3 patients, sepsis in 2, respiratory failure due to over-sedation in 1, subcapsular hematoma in 1, and intrahepatic arterioportal fistula in 1. The incidence of complications of PTLB in patients with biopsy alone and those with simultaneous interventions was 0.49% and 3.19%, respectively (p = .023). Patients who developed acute cholangitis, respiratory failure, subcapsular hematoma, and arterioportal fistula improved with non-operative management. Of two patients with sepsis, one underwent PTLB and percutaneous transhepatic portal vein balloon dilatation and developed fever and seizures the following day. Sepsis was treated with antibiotic therapy. Another patient who underwent PTLB and exchange of percutaneous transhepatic biliary drainage catheter developed fever and impaired consciousness immediately. Sepsis was treated with antibiotic therapy, mechanical ventilation, and continuous hemofiltration. CONCLUSIONS: Percutaneous transhepatic liver biopsy after pediatric LT is safe. However, combining liver biopsy with simultaneous procedures for vascular and biliary complications is associated with an increased risk of complications.

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.

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.

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.

BACKGROUND The number of pregnancies after liver transplantation (LT) is increasing; however, the safety and incidence of complications associated with these pregnancies are still unclear. In this report, we retrospectively assessed the influences and problems associated with post-transplant pregnancy on allografts, recipients, and fetuses. MATERIAL AND METHODS A total of 14 pregnancies were identified in 8 female recipients between 2005 and 2018. The original disease was biliary atresia in all recipients. We provide a basic guide for the management of planned pregnancies in female recipients. RESULTS Of the 7 planned pregnancies, no recipients took mycophenolate mofetil (MMF) or had allograft liver dysfunction. Among the 7 unplanned conceptions, we judged that the pregnancy was inadequate to continue in 4 recipients due to taking MMF and 2 recipients due to allograft liver dysfunction at conception. However, 4 recipients who immediately stopped taking MMF continued with their pregnancies. Ten pregnancies resulted in live 11 births. Among obstetric complications or fetal and neonatal complications, gestational diabetes mellitus in 3 recipients was the most common. There were 3 miscarriages and 1 planned termination because of MMF medication and liver dysfunction. CONCLUSIONS Planned pregnancies in LT recipients can lead to the birth of a healthy baby and no influence on either the allograft or the recipient. However, unplanned pregnancies in LT recipients, such as recipients who take MMF or have allograft liver dysfunction, may have an adverse influence on the fetus.

PURPOSE: Advances in interventional radiology (IVR) treatment have notably improved the prognosis of hepatic vein (HV) and portal vein (PV) complications following pediatric living donor liver transplantation (LDLT); however, graft failure may develop in refractory cases. Although endovascular stent placement is considered for recurrent stenosis, its indications are controversial. METHODS: We enrolled 282 patients who underwent pediatric LDLT in our department from May 2001 to September 2016. RESULTS: 22 (7.8%) HV complications occurred after LDLT. Recurrence was observed in 45.5% of the patients after the initial treatment, and 2 patients (9.1%) underwent endovascular stent placement. The stents were inserted at 8 months and 3.8 years following LDLT, respectively. After stent placement, both patients developed thrombotic obstruction and are currently being considered for re-transplantation. 40 (14.2%) PV complications occurred after LDLT. Recurrence occurred in 27.5% of the patients after the initial treatment, and 4 patients (10.0%) underwent endovascular stent treatment. The stents of all the patients remained patent, with an average patency duration of 41 months. CONCLUSION: Endovascular stent placement is an effective treatment for intractable PV complications following pediatric LDLT. However, endovascular stent placement for HV complications should be carefully performed because of the risk of intrastent thrombotic occlusion and the possibility of immunological venous injury.