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J Pirenne

Publications and source records attributed to J Pirenne.

At least 19 recordsLinked to original sources
PubMed2006

The clinicopathological and prognostic relevance of cytokeratin 7 and 19 expression in hepatocellular carcinoma. A possible progenitor cell origin.

AIMS: Cytokeratin (CK) 7 and CK19 expression, present in hepatic progenitor cells (HPCs) and in cholangiocytes but not in normal hepatocytes, has been reported in some hepatocellular carcinomas (HCCs); however, the incidence and relevance of this expression in HCC in Caucasians is not known. Therefore, our aim was to study the occurrence and clinicopathological characteristics of HCC expressing CK7 and/or CK19 in 109 Caucasian patients. METHODS AND RESULTS: The expression of hepatocellular differentiation markers (Hepar, canalicular polyclonal carcinoembryonic antigen), biliary/progenitor cell markers (CK7, CK19), alpha-fetoprotein (AFP), p53 and beta-catenin in HCC was semiquantitatively assessed by immunohistochemistry. Of 109 HCCs, 78 were CK7-/CK19- (72%), 13 CK7+/CK19- (12%), seven CK7-/CK19+ (6%), 11 CK7+/CK19+ (10%). CK19 expression was significantly associated with elevated serum AFP (400 ng/ml) (P = 0.023), tumour AFP expression (P < 0.0001), presence in serum of anti-hepatitis B core (P = 0.016), less fibrosis in non-neoplastic parenchyma (P = 0.009) and less nuclear beta-catenin expression (P = 0.021). CK7 expression was significantly associated with elevated serum bilirubin (> 2 mg/dl) (P = 0.0005) and less nuclear beta-catenin expression (P = 0.003). HCC expressing CK19 had a higher rate of recurrence (P = 0.009, hazard ratio 12.5, n = 31) after liver transplantation compared with CK19- tumours. CONCLUSIONS: In our series, 28% of HCCs contained cells expressing CK7 and/or CK19. They potentially derive from HPCs. The higher recurrence rate of CK19+ HCC after transplantation suggests a worse prognosis for these HCCs compared with CK19- HCC.

Adult↗
PubMed2005

Liver transplantation using cavoportal transposition: an effective treatment in patients with complete splanchnic venous thrombosis.

Complete venous thrombosis of the splanchnic system remains a major challenge in liver transplantation surgery. Some of these patients have been treated successfully by multivisceral transplantation. Cavoportal transposition is another alternative to treat these patients. We reviewed our single-center experience with this technique. Five patients with operatively confirmed complete splanchnic thrombosis were transplanted with the cava portal transposition technique. All survived the procedure; 60% survived long term. This technique is a useful salvage procedure in moribund patients with diffuse portal thrombosis who would otherwise rapidly succumb.

Adult↗
PubMed2005

Liver transplantation using livers from septuagenarian and octogenarian donors: an underused strategy to reduce mortality on the waiting list.

Shortage of liver grafts is the only limiting factor for application of liver transplantation and causes an increasing mortality on the waiting list. Very old donors (>70 to 80 years old) are rarely referred to transplant centers because of the assumption that these livers will not work properly. Alternatively, transplant teams may be reluctant to use these very old livers due to the risk of poor posttransplant outcome. We reviewed our experience with seven liver transplantations using very old donor livers. We found that the results in terms of graft function and patient survival are adequate. Interestingly, the majority of these donors originated from a single referring donor unit (of more than 20 units who belong to our donor network) that systematically refers all brain-dead donors to the transplant center, independent of the age of the potential donor. This implies that many of these donors are left undetected in other units. In conclusion, very old donors should be referred to transplant centers since results of transplantation with these grafts are favorable.

Age Factors↗
PubMed2005

Nodular regenerative hyperplasia, portal vein thrombosis, and avascular hip necrosis due to hyperhomocysteinaemia.

A male patient with portal hypertension, portal vein thrombosis, spontaneous splenorenal shunt formation, and encephalopathy, thought to have post-hepatitis B cirrhosis, is described. His condition deteriorated and necessitated liver transplantation. In the explant liver, nodular regenerative hyperplasia with pronounced vascular lesions both in portal venules and in arterioles was found instead of classical cirrhosis. Two years post-transplant he developed bilateral ischaemic femur head necrosis. The three disorders (portal vein thrombosis, nodular regenerative hyperplasia, and ischaemic hip necrosis) seemed to be due to a common vasculopathy induced by hyperhomocyteinaemia. Genetic studies showed that he carried a mutation in the gene encoding for formation of methylenetetrahydrofolate reductase. Treatment with folic acid combined with pyridoxine (vitamin B6) and cyanocobalamin (vitamin B12) normalised his serum homocysteine levels.

Femur Head Necrosis↗
PubMed2005

Case report: hepatic artery pseudoaneurysm after liver transplantation: definitive treatment with a stent-graft after failed coil embolisation.

A 69-year-old woman presented with massive upper gastrointestinal bleeding owing to a ruptured hepatic pseudoaneurysm located at the surgical arterial anastomosis, 2 months after combined liver and kidney transplantation. Initially the pseudoaneurysm was successfully coiled but 3 weeks later recurrence of her symptoms occurred. Hepatic angiography revealed partial reperfusion of the coiled pseudoaneurysm; definitive treatment was performed by placement of an expanded-polytetrafluoroethylene (e-PTFE) covered coronary stent-graft, completely excluding the pseudoaneurysm. Radiological follow-up studies demonstrate a patent stent-graft functioning normally.

Aneurysm, False↗
PubMed2004

[Intestinal transplantation from the laboratory to the clinic].

The short bowel syndrome is caused by the anatomical or functional loss of more than 75% of the small bowel. These patients are currently dependent upon long-term total parenteral nutrition (TPN), a treatment that has made much progress, but which is not devoid of complications and which alters the quality of life. Transplantation of a new bowel is the only curative treatment for this disease. But intestinal transplantation (Itx) is not yet considered as an alternative to TPN. Itx is rendered difficult by the immunological obstacles, in particular a vigorous rejection response and the capacity of the bowel graft to induce a graft-versus-host disease (GVHD). Currently only profound and chronic immunosuppression is capable of controling this alloimmune response, but this is at the cost of infection, lymphoma and direct drug toxicity. For this reason Itx is currently rarely performed and usually seen as a "last chance" treatment for terminal patients with life-threatening complications of TPN. The last 10 years, there has been much research performed on Itx. Rejection and GVHD have been better characterized in small and large animal models. Some mechanisms of this alloimmune response have been delineated. Reproducible surgical techniques have been developed in large animal models. Immunomodulatory strategies have been developed that can help to control rejection and reduce the need for immunosuppression. The lessons learned from these experiments--in particular the surgical models that were developed and the immunomodulatory strategies that were designed--were applied in a clinical Itx programme. In October 2000 and in June 2002, 2 Itx were performed in patients with a short bowel syndrome and life-threatening liver failure caused by TPN. Both patients are doing well and have developed no episode of rejection or GVHD so far. This is despite the fact that they are receiving extremely low immunosupppression for this type of transplant. Currently those 2 patients are physically completely rehabilitated and can eat normally again.

Animals↗
PubMed2003

Break of tolerance via donor-specific blood transfusion by high doses of steroids: a differential effect after intestinal transplantation and heart transplantation.

UNLABELLED: Tolerance requires active mechanisms. How immunosuppressors affects tolerance is poorly understood. METHODS: RA (RT1(p))/PVG (RT1(c)) rats were used as donor/recipient. Intestinal and heart transplant model were selected as highly and poorly immunogenic organs. Studied groups were 1, rejecting control; 2, received peritransplant steroids; 3, donor-specific blood transfusion (DSBT); 4, DSBT plus peritransplant steroids; and 5, DSBT+periDSBT Ste. RESULTS: Intestinal transplant recipients in group 1 died on posttransplant day (d) 18. In group 2, steroids did not change survival (17 days, P >.05 versus group 1). With DSBT (group 3), all rats survived >75 days, whereas with steroids those in group 4 survived 59 days (P >.05 vs group 3) and group 5 survived 51 days (P <.05 versus group 3). Survivors in group 2 were tolerant as evidenced by acceptance of secondary donor-specific (not third-party) graft. However, 100% and 33% of donor-specific secondary grafts were rejected in groups 4 and 5 (P <.05 and P >.05 versus group 3). In heart transplants, steroid treatment had no effect on graft survival (group 1 9 days; group 2 9 days; P >.05). DSBT (group 3) induced 100% tolerance (primary: >100 days, secondary: 100%). Unlike in intestinal transplantation, adjunction peritransplant steroids (group 4) allowed 100% of primary and 83% of secondary graft acceptance (P >.05 versus group 3). In group 5, (DSBT+periDSBT steroids) acceptance of primary and secondary grafts tended to be reduced (primary: 77 days; P >.05 versus group 3; secondary: 67%, P >.05 versus group 3). CONCLUSION: Steroid induction did not prolong graft survival after either intestinal or heart transplant. Adjunction of steroids to a DSBT tolerogenic regimen caused rejection of primary and secondary grafts, particularly after intestinal transplantation. Routine use of steroids in the clinics must be reconsidered, particularly when immunogenic organs are transplanted and when immunomodulation is applied.

Animals↗
PubMed2003

The use of an anti-CD25 monoclonal antibody and mycophenolate mofetil enables the use of a low-dose tacrolimus and early withdrawal of steroids in renal transplant recipients.

BACKGROUND: Reducing calcineurin-inhibitor-induced nephrotoxicity and simultaneously avoiding long-term steroid related side-effects is a desirable goal in renal transplantation. We examined the hypothesis that using anti-CD25 monoclonal antibody induction and mycophenolate mofetil (MMF) would allow the lowering of target pre-dose blood concentrations of tacrolimus immediately after transplantation and subsequently stopping steroids at 5 months. METHODS: Eighty-two kidney recipients were enrolled in a single-center study comparing two tacrolimus-based protocols. Group I (n = 41) patients received a standard-dose tacrolimus (blood concentration 10-15 ng/mL) with MMF and a standard dose corticosteroid. Group II (n = 41) patients were treated with a low-dose tacrolimus (blood concentration 5-10 ng/mL) and MMF, a low-dose corticosteroid (stopped after 5 months) and induction with daclizumab. RESULTS: Patient (95.1 versus 100%) and graft survival (92.6 versus 97.5%) at 1 yr were not different between groups. Patients of group II experienced significantly less acute rejections than group I (17.1 versus 41.4% p = 0.03). Delayed graft function occurred less often in group II (5 versus 12% p = 0.43). Graft function at 1 yr was significantly better in group II (serum creatinine 1.49 versus 1.69 mg/dL and creatinine clearance 59.6 versus 49 mL/min; p < 0.05). Corticosteroids could be stopped after 5 months in 82.9% of group II patients. CONCLUSION: A regimen consisting of anti-CD25 monoclonal antibody induction and MMF allows the safe and efficient use of low-target pre-dose trough concentrations of tacrolimus and enables the early discontinuation of steroids. Preliminary results indicate a better 1-yr graft function compared to a normal-dose tacrolimus regimen.

Antibodies, Monoclonal↗
PubMed2003

Pancreatic transplantation.

Pancreas transplantation is the only treatment of Type I diabetes that consistently establishes an insulin-independent, normoglycemic state. Currently long-term insulin-independence is achieved in > 80% of recipients of pancreas grafts placed simultaneous with the kidney and in > 70% of recipients of a pancreas after a kidney and non-uremic recipients of a pancreas alone. The penalty is immunosuppression, already obligatory for a kidney recipient, but the benefits are improved quality of life and the effect that perfect control of glycemia can have on secondary complications of diabetes.

Adult↗
PubMed2003

Long-term changes in mycophenolic acid exposure in combination with tacrolimus and corticosteroids are dose dependent and not reflected by trough plasma concentration: a prospective study in 100 de novo renal allograft recipients.

Tacrolimus and cyclosporine A have different effects on exposure to concomitantly administered mycophenolate mofetil (MMF), measured as the mycophenolic acid (MPA) dose interval area under the plasma concentration versus time curve (AUC0-12 h) or the plasma MPA predose concentration (C0). This has led to recommendations in using a 50% lower dose of MMF in combination with tacrolimus compared to cyclosporin A. At present, no long-term data are available regarding the pharmacokinetics (PK) of different dosages of MMF in combination with tacrolimus and the clinical variables that influence the dose-exposure relationship of MPA. A prospective 12-month pharmacokinetic study was performed in 100 de novo renal transplant recipients treated with two different MMF dosages (1 g/day vs. 2 g/day) in combination with tacrolimus and corticosteroids. MPA AUC data were collected 7 days, 6 weeks, and 3 and 12 months posttransplantation, and model-independent PK parameters were calculated. Clinical variables that could possibly influence MPA PK were evaluated. The MPA AUC0-12 h significantly increased toward 6 weeks (p < 0.05) but only in the 2-g MMF dosing group. The MPA AUC0-12 h in the 1-g MMF group reached its nadir at 3 months, while in the 2-g MMF group, it remained elevated until 3 months, returning to baseline values by 12 months. This differential evolution in exposure was not only inadequately reflected by the corresponding MPA C0 concentrations, but the MPA C0 concentrations also were not significantly different between the two dosing groups at early postgrafting (day 7) and at 12 months. Using multiple stepwise regression analysis, C0 (r = 0.51, p < 0.0001) and end-of-dose interval MPA plasma concentration (C12: r2 = 0.61, p < 0.0001) were found to poorly predict MPA AUC0-12 h, while MPA plasma concentrations at 4 hours (C4: r2 = 0.85, p < 0.0001) and 6 hours postdosing (C6: r2 = 0.83, p < 0.0001) were superior but hampered by a large prediction bias and imprecision. An abbreviated 2-hour AUC measurement (r2 = 0.78), using three sampling points (C0, C40 [MPA plasma concentration 40 min postdosing], C2), provided the best compromise between a monitoring tool that is theoretically ideal and practically feasible. MPA pharmacokinetics were not influenced by recipient age, gender, and body weight or by serum albumin concentrations, allograft function, or corticosteroid or tacrolimus dose. Mild hepatic dysfunction early after grafting did result in significantly reduced MPA exposure (MPA AUC0-12 h, p = 0.01 and C0, p = 0.03). In this study, it was demonstrated for the first time that the dynamics of long-term MPA pharmacokinetics in combination with tacrolimus differ according to the daily MMF dose and that this effect is not adequately reflected by MPA trough concentrations. Using the latter as a routine measure for therapeutic drug monitoring might mislead clinicians into drawing wrong conclusions in terms of relating questions of efficacy or toxicity to MPA exposure.

Analysis of Variance↗
PubMed2001

Posttransplantation diabetes mellitus in FK-506-treated renal transplant recipients: analysis of incidence and risk factors.

BACKGROUND: The development of posttransplantation diabetes mellitus has a major impact on the quality of life and long-term outcome. METHODS: One hundred thirty-nine patients without known glucose metabolism abnormalities and treated with FK-506, methylprednisolone, and mycophenolate mofetil/azathioprine were analyzed for incidence of and risk factors for developing impaired fasting glycemia (IFG) and diabetes mellitus (DM). RESULTS: Using the American Diabetes Association criteria, 15% developed IFG and 32% developed DM in the first year after transplantation. High trough levels of FK-506 during the first month after transplantation (especially >15 ng/ml) and high body mass index (BMI) were significant risk factors for IFG or DM. Patients with (steroid-treated) acute rejections in addition to high trough levels of FK-506 were most prone to develop DM, whereas high BMI conferred risk of developing IFG. Patients with posttransplantation glycemic abnormalities also had higher levels of serum triglycerides at the time of transplantation, but they needed a lower dose of FK-506 to obtain higher trough levels of FK-506, suggesting metabolic differences already present before transplantation. The only risk factor retained for persistent IFG or DM beyond the first year was a higher number of trough levels of FK-506 >15 ng/ml during the first month after transplantation. CONCLUSIONS: Induction with an FK-506 based immunosuppressive regimen resulted in a high incidence of glucose metabolism disorders in renal transplantation recipients. Higher trough levels of FK-506 during the first month, acute rejections, and higher BMI were the most obvious risk factors.

Adult↗
PubMed2001

Recent advances and future prospects in intestinal and multi-visceral transplantation.

From an experimental procedure, intestinal transplantation (ITx) has evolved over the last 10 yr into a treatment option for patients suffering from short bowel syndrome and who develop life-threatening complications from total parenteral nutrition (TPN) (e.g. liver dysfunction, line sepsis, shortage of venous access, etc.). One-year survival rates are approximately 70% and thus similar to lung Tx. However, the intestine remains the most challenging abdominal organ to transplant. This is because of the severe immune response (mostly rejection) that is produced, and therefore the need for profound immunosuppression with its attendant complications (sepsis, lymphoma, direct drug toxicity). Unlike other organs, graft loss as a result of acute rejection can occur late after transplantation (more than 1 yr post-transplant). With regard to the actual immunosuppressive regimens, considerable experience in patient management is required to optimize outcome of those complex transplants, which are permanently at risk of rejection and infection. ITx remains an unfinished product, and the application of ITx to patients doing well on TPN warrants further research in the understanding of the rejection process, in the development of less toxic and more efficient immunosuppressive protocols, and in the development of immunomodulatory strategies, to better control rejection and thereby reduce the need for immunosuppression.

Adjuvants, Immunologic↗
PubMed2001

Liver transplantation for polycystic liver disease.

Polycystic liver disease (PLD) may provoke massive hepatomegaly and severe physical and social handicaps. Data on orthotopic liver transplantation (OLT) for PLD are rare and conflicting. Conservative surgery (resection or fenestration) is indicated for large single cysts, but its value for small diffuse cysts is questionable. In addition, conservative surgery is not devoid of morbidity and mortality. OLT offers the prospect of a fully curative treatment, but controversy remains because those patients usually have preserved liver function. Thus, we reviewed our experience with OLT for PLD. Sixteen adult women underwent OLT for small diffuse PLD between 1990 and 1999. Mean age was 45 years (range, 34 to 56 years). Fourteen patients had combined liver and kidney cystic disease, but only 1 patient required combined liver and kidney transplantation, whereas 13 patients underwent OLT alone. Two patients had isolated PLD. Indications for transplantation were massive hepatomegaly causing physical handicaps (n = 16), social handicaps (n = 16), malnutrition (n = 4), and cholestasis and/or portal hypertension (n = 5). OLT caused no technical difficulty in 15 of 16 patients (surgery duration, 6.8 hours; range, 5 to 8 hours), with blood transfusions of 7.9 units (range, 0 to 22 units). One patient who underwent attempted liver-mass reduction pre-OLT died of bleeding and pulmonary emboli. Native liver weight was 10 to 20 kg. Posttransplantation immunosuppression consisted of cyclosporine or FK506, azathioprine, and steroids (discontinued at 3 months). Morbidity included biliary stricture (2 patients), revision for bleeding and hepatitis (1 patient), pneumothorax and subphrenic collection (1 patient), and tracheostomy (1 patient). One patient died of lung cancer 6 years posttransplantation. Both patient and graft survival rates are 87.5% (follow-up, 3 months to 9 years). Of 15 patients who underwent OLT alone, only 1 patient needed a kidney transplant 4 years after OLT. Kidney function has remained satisfactory in the other patients despite the use of cyclosporine or FK506 (last follow-up creatinine level, 1.55 mg/dL; range, 0.80 to 2.85 mg/dL). OLT had a dramatic impact on daily quality of life, enabling these patients to go back to a fully active life style. OLT offers the chance of a definitive treatment in patients with extensive, small, diffuse PLD that has evolved into severely handicapping hepatomegaly. In contrast to previous studies, combined liver and kidney transplantation is rarely needed. Patient symptoms and chances of definitive palliation offered by OLT must be balanced against the risks of transplantation and lifelong commitment to immunosuppression.

Adult↗