Centrilobular necrosis in children after combined liver and small bowel transplantation

Beyond 10 years, with or without an intestinal graft: Present and future?

Long-term outcomes in children undergoing intestinal transplantation remain unclear. Seventy-one children underwent intestinal transplantation in our center from 1989 to 2007. We report on 10-year posttransplant outcomes with (group 1, n = 26) and without (group 2, n = 9) a functional graft. Ten-year patient and graft survival rates were 53% and 36%, respectively. Most patients were studying or working, one third having psychiatric disorders. All patients in group 1 were weaned off parenteral nutrition with mostly normal physical growth and subnormal energy absorption. Graft histology from 15 late biopsies showed minimal abnormality. However, micronutrient deficiencies and fat malabsorption were frequent; biliary complications occurred in 4 patients among the 17 who underwent liver transplantation; median renal clearance was 87 mL/min/1.73 m² . Four patients in group 1 experienced late acute rejection. Among the 9 patients in group 2, 4 died after 10 years and 2 developed significant liver fibrosis. Liver transplantation and the use of a 3-drug regimen including sirolimus or mycophenolate mofetil were associated with improved graft survival. Therefore, intestinal transplantation may enable a satisfactory digestive function in the long term. The prognosis of graft removal without retransplantation is better than expected. Regular monitoring of micronutrients, early psychological assessment, and use of sirolimus are recommended.

Microvillous inclusion disease: how to improve the prognosis of a severe congenital enterocyte disorder

BACKGROUND AND OBJECTIVE

Microvillous inclusion disease (MVID) is a rare congenital enterocyte disorder causing severe diarrhea and intestinal failure. The objective of this study was to analyze clinical evolution and the most frequent complications of MVID in children receiving parenteral nutrition (PN) and after small-bowel transplantation (SBTx) with the aim to improve treatment strategies and prognosis.

PATIENTS AND METHODS

From 1995 to 2009, 24 patients (16 boys, median follow-up 4.7 years, range: from birth to 23.5 years) with MVID were admitted to our unit. The recorded parameters included growth, neurological development, liver and renal functions, bone disease, and outcome.

RESULTS

Almost half of the children were from consanguineous families from the Mediterranean area. All of the patients completely depended on PN. Four children died of PN complications before 4 years of age. Before or without SBTx, growth failure was common (mean height -2.5 standard deviations [SD]), as was developmental delay (12/24), liver (20/22 with fibrosis) or kidney disease (3/23 with moderate renal insufficiency), and osteoporosis (6/24). Thirteen children underwent SBTx (9 isolated, 4 combined with liver Tx) at a median age of 3.5 years. Follow-up after SBTx was 0.4 to 14 years. Patient survival rates were 63% without SBTx and 77% with SBTx. After SBTx, 4 children experienced catch-up growth.

CONCLUSIONS

PN in MVID is difficult to manage and requires expertise. Despite improved results in expert centers, the risk of death or irreversible sequelae is higher with PN than after Tx. SBTx, despite being complicated, remains the only hope to improve the quality of life and long-term prognosis of these children.

Significance of central perivenulitis in pediatric liver transplantation

Central perivenulitis (CP) encompasses dropout of zone 3 hepatocytes, red blood cell extravasation, and perivenular mononuclear inflammation. In the liver transplant setting, CP can occur in isolation or it can occur in association with portal-based disease such as acute cellular rejection (PB-ACR). Some CP is also thought to be a manifestation of chronic rejection, particularly when accompanied by zone 3 fibrosis. Prior studies of CP in pediatric liver allografts have been hampered by lack of protocol biopsies and low rates of histologic follow-up. We studied 62 consecutive liver allografts from 55 pediatric patients (age: < or =18 y) who underwent transplant from the years 1995 to 2007. Forty-nine allografts (79%) had > or =1 year of histologic follow-up, 32 (52%) > or =3 years, and 24 (39%) > or =5 years. We reviewed a total of 445 allograft biopsies (mean: 7.2 per allograft) obtained at 2 days to 11 years; 213 (48%) of these were protocol biopsies. Seven explanted livers that were removed during the course of retransplantation for graft failure in this group were also reviewed. All specimens were scored for the following features: (1) CP (mild, moderate, and severe), (2) portal ACR (mild, moderate, and severe), (3) zone 3 fibrosis (mild=perivenular or severe=bridging), and (4) ductopenia. CP was present in 120 (27%) of 445 biopsies, including 73 with CP+PB-ACR, 16 with CP within 1 month of PB-ACR, 27 with isolated CP, 3 with CP+de-novo autoimmune hepatitis, and 1 with CP+Epstein-Barr virus infection. Overall, CP was observed on at least 1 occasion in 41 (66%) allografts. It was not associated with any specific liver function test abnormality or pattern of liver function test abnormalities, it was not associated with vascular compromise as judged by Doppler ultrasound examinations, and it was not related to type of immunosuppression. CP overall was equally prevalent in the early (< or =3 mo) and late (>3 mo) post-transplant periods, but isolated CP increased in the late period. On follow-up, 6 (15%) of 41 allografts with CP developed ductopenic chronic rejection (4 requiring retransplantation) and 10 (25%) developed zone 3-based fibrosis without ductopenia (2 severe, 8 mild). In contrast, none of the 21 allografts without CP developed chronic rejection (P=0.09) and none had zone 3-based fibrosis on their last biopsy (P<0.001). All patients who developed ductopenia had 1 or more episodes of CP+PB-ACR. In contrast, isolated CP [seen in 17 (27%) allografts on at least 1 occasion] was associated with zone 3-based fibrosis in 50%, but did not lead to ductopenic chronic rejection. These results underscore the high frequency of CP in pediatric liver transplantation, occurring in 27% of all allograft biopsies and 66% of allografts overall. CP is most common in conjunction with portal ACR, where it carries a significant risk for the development of zone 3 fibrosis and a trend toward the development of ductopenic chronic rejection.

Auxiliary en-bloc liver-small bowel transplantation with partial pancreas preservation in pigs

AIM

The aim of this study was to describe an auxiliary combined liver-small bowel transplantation model with the preservation of duodenum, head of pancreas and hepatic biliary system in pigs. The technique, feasibility, security and immunosuppression were commented.

METHODS

Forty outbred long-white pigs were randomized into two groups, and the auxiliary composite liver/small bowel allotransplantations were undertaken in 10 long-white pigs in each group with the recipient liver preserved. Group A was not treated with immunosuppressive drugs while group B was treated with cyclosporine A and methylprednisolone after operation. The hemodynamic changes and amylase of body fluid (including blood, urine and abdominal drain) were analyzed.

RESULTS

The average survival time of the animals was 10+/-1.929 d (6 to 25 d) in group A while more than 30 d in group B. The pigs could tolerate the hemodynamic fluctuation during operation and the hemodynamic parameters recovered to normal 2 h after blood reperfusion. The transient high amylase level was decreased to normal one week after operation and autopsy showed no pancreatitis.

CONCLUSION

Auxiliary en-bloc liver-small bowel transplantation with partial pancreas preservation is a feasible and safe model with simplified surgical techniques for composite liver/small bowel transplantation. This model may be used as a preclinical training model for clinical transplantation method, clinical liver-small bowel transplantation related complication research, basic research including immunosuppressive treatment, organ preservation, acute rejection, chronic rejection, immuno-tolerance and xenotransplantation.

New perspectives for children with microvillous inclusion disease: early small bowel transplantation

BACKGROUND

Microvillous inclusion disease (MVID) is a congenital intestinal epithelial cell disorder leading to lifelong intestinal failure. Despite long-term total parenteral nutrition, life expectancy is extremely reduced because of metabolic or septic complications or liver failure.

METHODS

Twelve patients with early-onset MVID were evaluated between 1995 and 2002 for the possibility of small bowel transplantation (SbTx). Three patients died before they could be placed on the waiting list for SbTx, and one patient is still awaiting SbTx. SbTx was contraindicated in one patient.

RESULTS

Seven of 12 patients (six boys and one girl) underwent transplantation (three SbTxs and four combined liver-SbTxs). Actuarial survival rates were 100% and 75% in the SbTx and combined liver-SbTx groups, respectively, with a mean follow-up of 3 years (1.1-8.5 years). In contrast, the survival rate was only 40% in the subgroup of five patients who did not undergo transplantation. After transplantation, all patients were weaned from parenteral nutrition: the five patients with an additional colon graft were weaned within 36 days as opposed to the others without colonic transplant who obtained full intestinal autonomy several months after transplantation. The only two surviving patients who did not undergo SbTx remain highly dependent on total parenteral nutrition, which is complicated by repeated episodes of metabolic decompensation.

CONCLUSIONS

SbTx alone or in combination with the liver is highly successful in children with MVID, offering them a long-term perspective for the first time. Associated colon grafting markedly improves the outcome and quality of life after SbTx in patients with MVID.

Centrilobular necrosis after orthotopic liver transplantation: association with acute cellular rejection and impact on outcome

Several studies have linked centrilobular necrosis (CN) to acute cellular rejection (ACR) following liver transplantation. However, it may be difficult to establish the diagnosis of ACR when the classic portal features are absent. The aim of the present study was to identify specific features that would help to recognize ACR in biopsies with CN. One hundred and forty liver biopsies with CN were identified from 97 patients who underwent liver transplantation. The following histopathologic features were assessed: CN, steatosis, lobular inflammation, cholestasis, endothelialitis, and fibrosis. CN was graded semiquantitatively. A number of clinical and biochemical parameters were also recorded. Biopsies with CN were assessed for the presence or absence of ACR and divided into two groups accordingly. The associations of the biochemical, pathologic, and clinical features with ACR were assessed using a multivariate logistic regression model. The outcomes of patients with and without rejection were compared using the Cox proportional hazards regression model. Seventy-four biopsies (52.9%) showed evidence of ACR, and 52 patients (53.6%) had evidence of ACR at the first biopsy with CN. The multivariate analysis showed the presence of cholestasis, lobular inflammation, the ALT level, and time since liver transplantation to be independent predictors of the presence of ACR in biopsies with CN. Patients with ACR on their first biopsy with CN were significantly more likely to experience graft loss compared with patients without ACR. In conclusion, the presence of cholestasis and lobular inflammation on biopsies with CN appeared helpful in predicting its association with ACR.

Therapy for acute rejection in pediatric organ transplant recipients

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.