Biomedical subjects
Publications and source records attributed to Christophe Chardot.
Adrenocortical oncocytoma is a rare epithelial tumor only described in adults. We report the case of a 12-year-old female who presented a left adrenal mass with abdominal pain, fatigue, acne vulgaris, and elevation of the androstenedione and total testosterone. She had an adrenalectomy. A diagnosis of adrenocortical oncocytoma was made after detailed histological, immunohistochemical, and ultrastructural studies.
BACKGROUND: Ex vivo liver gene therapy provides an attractive alternative to orthotopic liver transplantation for the treatment of liver diseases. We previously reported a protocol in which human primary hepatocytes are highly transduced in Suspension with Lentiviral vectors and Immediately Transplanted (SLIT). Here, we evaluated the SLIT approach in Gunn rats, the animal model for Crigler-Najjar syndrome type 1, a defect in bilirubin UDP-glucuronosyltransferase (BUGT). METHODS: We constructed lentiviral vectors coding for BUGT under control of an ubiquitous promoter. Control vectors contained Green Fluorescent Protein (GFP) under control of the same promoter. Hepatocytes were isolated from jaundiced Gunn rats and transduced in suspension for four hr. After washing, 2x10 hepatocytes were immediately transplanted into syngeneic rats. Bilirubinemia and bile pigments were regularly assessed after cell transplantation. The percentage and presence of transduced hepatocytes was analyzed by immunohistochemistry in GFP-transplanted animals. RESULTS: In rats receiving BUGT-transduced hepatocytes, bilirubinemia decreased by about 30%. The level of correction remained stable for up to 240 days. Bilirubin glucuronides were present in the bile of treated animals, indicating the metabolic activity of engrafted hepatocytes. In contrast, bilirubinemia in GFP-transplanted rats did not decline but rather increased. GFP-positive hepatocytes amounted to 0.5-1% of the liver, which is in agreement with the number of transplanted and genetically-modified hepatocytes (6x10). CONCLUSIONS: This work reports the first demonstration of long-term metabolic benefit after rapid transplantation of ex vivo lentivirally tranduced hepatocytes. Therefore, this study demonstrates the therapeutic proof-of-principle and potential of the SLIT approach for treating inherited metabolic liver diseases.
Biliary atresia (BA) is a rare disease characterised by a biliary obstruction of unknown origin that presents in the neonatal period. It is the most frequent surgical cause of cholestatic jaundice in this age group. BA occurs in approximately 1/18,000 live births in Western Europe. In the world, the reported incidence varies from 5/100,000 to 32/100,000 live births, and is highest in Asia and the Pacific region. Females are affected slightly more often than males. The common histopathological picture is one of inflammatory damage to the intra- and extrahepatic bile ducts with sclerosis and narrowing or even obliteration of the biliary tree. Untreated, this condition leads to cirrhosis and death within the first years of life. BA is not known to be a hereditary condition. No primary medical treatment is relevant for the management of BA. Once BA suspected, surgical intervention (Kasai portoenterostomy) should be performed as soon as possible as operations performed early in life is more likely to be successful. Liver transplantation may be needed later if the Kasai operation fails to restore the biliary flow or if cirrhotic complications occur. At present, approximately 90% of BA patients survive and the majority have normal quality of life.
This study analyzed the results of the decentralized management of biliary atresia (BA) in France, where an improved collaboration between centers has been promoted since 1997. Results were compared to those obtained in England and Wales, where BA patients have been centralized in three designated centers since 1999. According to their birth dates, BA patients were divided into two cohorts: cohort A, with patients born between 1986 and 1996, had 472 patients; and cohort B, with patients born between 1997 and 2002, had 271 patients. Survival rates were calculated according to the Kaplan-Meier method and compared by using the log rank test and the Cox model. Four-year overall BA patient survival was 73.6% (95% CI 69.5%-77.7%) and 87.1% (CI 82.6%-91.6%) in cohorts A and B, respectively (P < .001). Median age at time of the Kasai operation was 61 and 57 days in cohorts A and B, respectively (NS). Four-year survival with native liver after the Kasai operation was 40.1% and 42.7% in cohorts A and B, respectively (NS): 33.9% (cohort A) and 33.4% (cohort B) in the centers with two or fewer caseloads a year, 30.9% (cohort A) and 44.5% (cohort B) in the centers with 3-5 cases/year, 47.8% (cohort A) and 47.7% (cohort B) in the center with more than 20 caseloads a year. In cohorts A and B, 74 (15.7%) and 19 (7%) patients, respectively, died without liver transplantation (LT). Four-year survival after LT was 75.1% and 88.8% in cohorts A and B, respectively (P = .006). In conclusion, BA patients currently have the same chance of survival in France as in England and Wales. The early success rate of the Kasai operation remains inferior in the centers with limited caseloads in France, leading to a greater need for LTs in infancy and early childhood.
Fulminant hepatic failure of unknown origin is the most common cause of fulminant hepatitis with high incidence of aplastic anaemia. Furthermore, the association of liver failure and aplastic anaemia has an increased mortality rate. In this report we describe a 16-month-old boy who presented with aplastic anaemia preceding a non-A, non-B, non-C fulminant liver failure. He developed severe graft versus host disease (GvHD) after liver transplantation, proven by the presence of donor cells in the peripheral blood and in the skin biopsy. He received conventional therapy (steroids, mycophenolate, anti-IL-2 monoclonal antibodies, anti-thymocyte globulin) without success. In an attempt to obtain T cell depletion and reduce the GvHD, he was treated with Alemtuzumab, a first time use for this indication. Aplastic anaemia was extensively investigated, especially exploring the possibility of primary immunodeficiency and reticular dysgenesis which were excluded based on clinical history. However, another form of primary immunodeficiency could be the cause of the uncontrollable proliferation of the donor lymphocytes derived from the liver transplant. Despite aggressive treatment GvHD progressed and the patient died of multiorgan failure. The majority of authors mention aplastic anaemia as a secondary event post liver transplant, whereas in our view this might be a haematopoietic stem cell disorder preceding fulminant hepatic failure. These patients also need to be evaluated extensively in order to exclude a primary immunodeficiency. The underlying disease will determine the choice of immunosuppressive treatment, especially in case of development of GvHD caused by the transplanted lymphocytes inhabiting the donor liver.
Explore the source record for details and available documents.
Retroperitoneal cystic lymphangioma is a rare benign tumor of the retroperitoneal lymphatics that usually manifests in infancy. If surgical excision is used in treatment, it needs to be as complete as possible to reduce the risk of recurrence. Two pediatric patients, an 18-month-old girl and a 4-yearold boy, underwent laparoscopic excision of symptomatic retroperitoneal cystic lymphangiomas. Macroscopically, the resection was complete in both cases. The postoperative course in both cases was uneventful. Both children remained asymptomatic and no recurrence was observed at 18-month follow-up. Complete laparoscopic excision should be considered as a therapeutic option to treat retroperitoneal cystic lymphangioma.
AIM: To examine the prognostic value of portal pressure at the time of Kasai operation in patients with biliary atresia (BA). PATIENTS AND METHODS: All 127 patients with BA, born between 1991 and 1996, who underwent a Kasai operation in Bicêtre Hospital were studied. Intraoperatively, the umbilical vein was catheterised and a portal pressure index (PPI), defined by the height of the physiologic saline column above the liver surface level, was measured. Overall patient survival, survival with native liver (SNL) and, in patients living with their native liver, survival without significant portal hypertension (SwsPHT) were calculated by Kaplan-Meier method and compared by univariate and multivariate analyses. RESULTS: Measurement of PPI was successful in 113/127 patients (89%) without complication. Median PPI was 15 cm (range, 5-35). Portal pressure index was positively correlated with age at surgery and histological severity of liver fibrosis. Ten-year overall patient survival was 78.2%; 10-year SNL was 35.7%. In patients living with their native liver, 5- and 10-year SwsPHT were 65.3% and 43.6%, respectively. Portal pressure index >15 cm, complete extrahepatic BA and polysplenia were independently associated with a worse SNL. Portal pressure index >15 cm and the absence of postoperative normalisation of bilirubin were independently associated with a worse SwsPHT. CONCLUSION: Biliary atresia patients with elevated portal pressure at the time of Kasai operation have lower chances of success of this procedure and a higher risk of developing portal hypertension, even if bilirubin levels normalise after the operation. Measurement of PPI was simple and safe and better predicted the postoperative outcome than did the histological scores of liver fibrosis.
To define the long-term prognosis of children undergoing the Kasai operation for biliary atresia, a retrospective study was undertaken comprising 271 patients operated between 1968 and 1983. Twenty years after surgery, 63 (23%) were alive with their native liver. Serum bilirubin was normal in 21 of these patients, 12 also had normal serum aminotransferase and gamma-glutamyltransferase activities, all but 2 had signs of cirrhosis, 44 had signs of portal hypertension, 19 had late bacterial cholangitis, and 6 had gallstones. Seven female patients gave birth to 9 children, and 3 male patients fathered 6 children. After age 20, 2 patients died of liver failure and 14 underwent or are awaiting liver transplantation. Twenty-year survival with native liver was significantly better in children with biliary atresia restricted to the hepatic ducts or with cysts at the porta hepatis. In conclusion, in the long term, less than 18% of infants with biliary atresia who are treated with corrective surgery may avoid liver transplantation, but even these patients require assiduous lifelong care.
The aim of this study was to review our experience in orthotopic liver transplantation (OLT) for biliary atresia (BA) in children and analyze the survival and prognostic factors, and long-term outcome. We reviewed 332 OLTs performed in 280 children between the years 1986 and 2000. Univariate and multivariate analysis were performed on patient and graft survivals according to recipients' and donors' characteristics as well as intraoperative data. The long-term outcome among the 80 children living at 10 years after OLT was studied according to growth, immunosuppressive therapy, and liver and renal functions. Liver graft status was eventually documented by liver biopsy. Status of rehabilitation was assessed by reviewing school performance and employment. Overall patient survival rates at 1, 5, and 10 years were 85, 82, and 82%, respectively, and the corresponding overall graft survival rates were 77, 73, and 71%. In the multivariate analysis, we identified 4 independent prognostic factors: polysplenia syndrome (P = .03), United Network for Organ Sharing (UNOS) status (P = .05), donor's age (P = .01), and perioperative surgical complications (P = .03). At 10 years after transplant, 80 children were alive and had normal growth rates. Liver histology was abnormal in 73% of these long-term survivors, mainly due to chronic rejection and centrilobular fibrosis. A total of 63 of the 80 children attended normal school and in 55 children (69%) school performance was not delayed. In conclusion, we discovered that a good long-term survival could be achieved after liver transplantation for BA, with a 82% survival rate at 10 years with normal scholastic studies in the majority of recipients.
Explore the source record for details and available documents.
PURPOSE: This study examines whether the intestinal lesions of necrotizing enterocolitis (NEC) in infants undergoing surgery are more severe in patients with extremely low birth weight (BW). METHODS: Between 1980 and 2000, 128 infants underwent laparotomy for NEC: 90 in the acute phase, and 38 for secondary stenosis. Resections were limited to areas of transparietal bowel necrosis and to secondary stenoses. The authors studied the extent of initial bowel lesions at initial laparotomy, and, in the survivors, the extent of bowel resections and the existence of digestive sequelae, with a median follow-up of 24 (range, 1 to 247) months. Children with BW < or =1,000 g (group 1, 22 patients) and greater than 1,000 g (group 2, 103 patients) were compared by using chi(2) and t test. RESULTS: Patients' survival rate was 87%: 68% and 91% in the groups 1 and 2, respectively (P =.01). No significant difference between the 2 groups was seen: (1) for the rate of patients with panintestinal lesions at initial surgery (12%); (2) in the survivors, the ratio of remaining to total length of jejuno-ileum (mean 88%), the number of colonic segments resected (mean 1.2), the rate of survivors without distal ileum (34%), ileo-caecal valve (39%), or right colon (29%); and (3) for the existence of digestive symptoms, even minor, at last follow-up (25%). CONCLUSIONS: Although the prognosis of surgical NEC was worse in infants with extremely low birth weight, the intestinal lesions were not found more severe in these patients.
Explore the source record for details and available documents.
Despite the availability of potent immunosuppressive drugs, rejection after organ transplantation in children remains a serious concern, and may lead to significant morbidity, graft loss, and death of the patient. Acute graft rejection in pediatric recipients is first treated with methylprednisolone pulses, followed by progressive taper of corticosteroid doses. After control of the rejection episode, baseline immunosuppression has to be adjusted and closely monitored since rejection (especially late episodes, occurring more than 6 months after transplantation) may be due to a lack of compliance or sub-therapeutic drug concentrations. The management of corticosteroid resistant rejection is not standardized, and depends on the transplanted organ and previous immunosuppressive regimen. In patients experiencing corticosteroid resistant acute rejection while on a cyclosporine-based immunosuppressive regimen, cyclosporine is generally changed to tacrolimus. In case of tacrolimus-based immunosuppression, tacrolimus blood levels may be increased, and/or mycophenolate mofetil (which nowadays tends to replace azathioprine) or sirolimus may be added, although pharmacodynamic data and clinical studies with these agents are still scarce in pediatric recipients. The use of antithymocyte globulins or monoclonal anti-CD3 antibodies, muromonab CD3 (OKT3) is hampered by numerous adverse effects, including a significant risk of over-immunosuppression. These therapies are nowadays indicated in very selected cases. Other treatments such as plasmapheresis and high dose immunoglobulins may be useful in difficult cases. In patients with refractory rejection despite therapeutic escalation, the risks of over-immunosuppression, including opportunistic infections and malignancies (especially the Epstein-Barr virus related post-transplant lymphoproliferative disease) have to be balanced with the consequences of graft loss due to rejection. Detransplantation or retransplantation may, in some instances, be preferable to severe infectious or tumoral complications.
BACKGROUND: Because cadaveric organ donors are in short supply, living donors are increasingly being used in transplantations. We have developed a safe and reproducible method for laparoscopic liver resection. METHODS: Left hepatic lobectomy (resection of segments 2 and 3) was done by laparoscopy in one woman aged 27 years and one man aged 31 years. The grafts were prepared under laparoscopy, without any vascular clamping, and were externalised through a suprapubic Pfannenstiel incision. Both grafts were transplanted conventionally to the patients' respective sons, who were both aged 1 year and had biliary atresia. FINDINGS: Donor operations lasted 7 h for the woman and 6 h for the man, and warm ischaemia times were 4 and 10 min, respectively. Blood loss was 150 and 450 mL, respectively, and no transfusions were required. Neither patient had complications during or after surgery; and hospital stay was 7 and 5 days, respectively. Both recipients are alive and have excellent graft function. INTERPRETATION: We have shown the feasibility of laparoscopic living donor hepatectomy from parent to child. If the safety and feasibility of this procedure can be shown in larger series, laparoscopic donor left lobectomy could become a new option for paediatric living donor liver transplantation.
BACKGROUND: In most cases of total hepatectomy (TH) required for hepatoblastoma (HB), the retrohepatic inferior vena cava (IVC) has to be removed with the native liver for complete tumor excision. Because the liver graft procured by living donation has no IVC, a reconstruction of the recipient IVC is needed. We report our experience with living-related liver transplantation (LRLT) and IVC replacement in such cases. METHODS: Between May 1998 and December 1999, four children underwent TH, including IVC and LRLT with IVC replacement for otherwise irresectable HB after chemotherapy (SIOPEL 2 and 3 protocols). IVC reconstruction used an allogenic iliac vein procured from a cadaveric donor (bank graft) in two cases and an internal jugular vein procured from the donor parent in two cases. Median age and weight at surgery were 17 months (range 10-60) and 9.6 kg (range 8.3-17.9). RESULTS: In the living donors, there were two complications of the procurement: one intra-abdominal biliary collection and one subcutaneous abscess. In all four children, complete excision of the tumor could be achieved without any intra-operative complication. One patient died 5 months after LRLT due to lung metastases. Three patients were alive and well with no evidence of tumor recurrence 13-24 months after surgery. Reconstructed IVC was patent in two patients, and asymptomatic thrombosis occurred 2 years after operation in one patient. CONCLUSION: Total hepatectomy including the retrohepatic IVC is not a technical obstacle to LRLT. Therefore, scheduled surgery, at the best time after chemotherapy, can be considered in all patients with otherwise irresectable HBs.
The use of tacrolimus in small pediatric graft recipients may require the availability of a suspension formulation for appropriate dose titration and easier administration. The pharmacokinetics (Pk) of an extemporaneously prepared oral suspension of tacrolimus (OST) was investigated in 15 pediatric liver transplant recipients, and was compared with the corresponding data with tacrolimus capsules (TC). Graft and patient survival rates were 100%. Acute rejection and steroid-resistant rejection were encountered in 9/15 and 3/15 patients, respectively. Comparison of Pk data showed a lower oral absorption of OST when compared with TC. No significant correlation could be made between the Pk parameters and rejection. Despite the lower bioavailability of OST when compared with TC, the rejection incidence was similar with both formulations (60% vs. 55%, respectively). Accordingly, the use of OST may constitute an alternative option for tacrolimus administration in low body weight organ recipients, to allow dosage titration in the early post-transplant weeks.