Up-to-date evolution of small bowel transplantation in children with intestinal failure

Intestinal Transplantation in Pediatric Patients

Intestine transplantation has evolved into a feasible alternative for children with permanent intestinal failure and life-threatening complications related to total parenteral nutrition. Although the first transplantations were done nearly 40 years ago, long-term survival has only been achieved in the last decade. Nearly 700 intestinal transplantations have been performed internationally since 1985, with an overall patient survival of greater than 50%. Improvements in patient selection, medical management, and assessment and treatment for rejection and infection have contributed to the increased survival. This article will discuss current results and medical management strategies for this innovative type of transplantation for children with end-stage short gut syndrome.

Intestine and multivisceral transplantation: current status and future directions

Intestinal failure and associated parenteral nutrition-induced liver failure cause significant morbidity, mortality, and health care burden. Intestine transplantation is now considered to be the standard of care in patients with intestinal failure who fail intestinal rehabilitation. Intestinal failure-associated liver disease is an important sequela of intestinal failure, caused by parenteral lipids, requiring simultaneous liver-intestine transplant. Lipid minimization and, in recent years, the emergence of fish oil-based lipid emulsions have been shown to reverse parenteral nutrition-associated hyperbilirubinemia, but not fibrosis. Significant progress in surgical techniques and immunosuppression has led to improved outcomes after intestine transplantation. Intestine in varying combination with liver, stomach, and pancreas, also referred to as multivisceral transplantation, is performed for patients with intestinal failure along with liver disease, surgical abdominal catastrophes, neuroendocrine and slow-growing tumors, and complete portomesenteric thrombosis with cirrhosis of the liver. Although acute and chronic rejection are major problems, long-term survivors have excellent quality of life and remain free of parenteral nutrition.

Outcomes in children with intestinal failure following listing for intestinal transplant

PURPOSE

The purpose of this study was to describe the population of pediatric patients waiting for intestinal transplant and to evaluate the risk of death or transplant by specific disease states.

METHODS

We studied the United Network for Organ Sharing (UNOS) database (Jan 1,1991 to 5/16/08) for patients 21 years old or younger at first listing for intestinal transplant and examined their age, sex, weight, and diagnoses. Time to list removal was summarized with cumulative incidence curves. Multinomial logistic regression was used to compare relative risk ratios for removal from the list for transplant, death, or other reasons.

RESULTS

We identified 1712 children listed for intestinal transplant (57% male, 51% <1 year, weight 8.1 kg [IQR, 6.1-14.1] at listing). Median age and weight at transplant (n = 852) were 1 year (IQR, 1-5) and 10 kg (IQR, 6.5-16.3). Regression analysis demonstrated significant differences in outcomes among disease conditions (P < .001). Compared to the gastroschisis group, the relative risk ratio for death versus transplant was higher in the necrotizing enterocolitis group (P = .015), lower in the short gut syndrome group (P = .001), and not different in the volvulus group (P = .94) after adjustment for weight and sex.

CONCLUSIONS

We conclude that the relative risk of transplant vs death varies significantly by the disease condition of the patient.

Extraction of diethylhexylphthalate by home total parenteral nutrition from polyvinyl chloride infusion lines commonly used in the home

OBJECTIVES

Recently, our group detected that polyvinyl chloride (PVC) perfusion lines leach large amounts of the toxic plasticizer diethylhexylphthalate (DEHP) under conditions typical of intensive care units. In the present study, we investigated the extraction of DEHP from PVC connecting tubes that are commonly used for total parenteral nutrition (TPN) solutions. The aim of the study was to estimate the amount of DEHP to which children receiving home TPN are exposed for months and years.

MATERIALS AND METHODS

1000 mL of TPN, identical in constitution and amount to the home TPN of 1 of our patients, were perfused through 5 different connecting tube systems and collected in hexane-rinsed glass bottles. The concentration of DEHP in the TPN was analyzed before and after perfusion.

RESULTS

Before perfusion of the lines, the solution had a DEHP concentration of 0.05 to 0.69 microg/mL (baseline value). After perfusion of the lines, the load of DEHP in the solution varied between 1.41 and 2.07 microg/mL. This TPN was established for children weighing 20 kg. The daily dosage is between 71 and 104 microg x kg(-1) x day(-1). TPN is administered at home for many months and years. The monthly charge of DEHP is between 42.3 and 62.1 mg. Children weighing 20 kg therefore receive a dosage between 2.1 and 3.1 mg x kg(-1) x month(-1).

CONCLUSIONS

Diethylhexylphthalate and its metabolite monoethylhexylphthalate have been demonstrated to be carcinogenic, embryotoxic, hepatotoxic, pneumotoxic, and cardiotoxic and are known to disrupt endocrine pathways and liver detoxifying capacity in animals. They are suspected of having multiple effects in humans as well. The doses presented above should therefore be avoided in children receiving home TPN by the use of tubing systems that are completely free of DEHP. Such systems are available.

Short bowel syndrome: parenteral nutrition versus intestinal transplantation. Where are we today?

Current management of short bowel syndrome (SBS) revolves around the use of home TPN (HPN). Complications include liver disease, catheter-related infections or occlusions, venous thrombosis, and bone disease. Patient survival with SBS on TPN is 86% and 75% at 2 and 5 years, respectively. Surgical management of SBS includes nontransplant surgeries such as serial transverse enteroplasty and reanastomosis. Small bowel transplant has become increasingly popular for management of SBS and is usually indicated when TPN cannot be continued. Posttransplant complications include graft-versus-host reaction, infections in an immunocompromised patient, vascular and biliary diseases, and recurrence of the original disease. Following intestinal-only transplants, patient and graft survival rate is 77% and 66% after 1 year. After 5 years the survival figures are 49% and 34%, respectively. Future improvements in survival and quality of life will enhance small bowel transplant as a viable treatment option for patients with SBS.

Study of the impact of liver transplantation on the outcome of intestinal grafts in children

BACKGROUND

Successful small bowel transplantation remains a challenge due to the septic and immune content of the gut. The possible beneficial role of the liver was assessed in pediatric recipients of isolated intestinal and liver intestinal combined transplantation, receiving the same immunosuppressive therapy.

METHODS

Fifteen children who underwent small bowel transplantation (seven SbTx) or combined liver-small bowel transplantation (eight LSbTx) at a single center between 1994 and 1998 were retrospectively reviewed and compared with fifteen controls (eight normal and seven appendicitis as inflammatory control). Transplant and patient survival, acute rejection episodes were analyzed and compared. Epithelial apoptotic body counts (ABC) and NF-kB (p65), Caspase-3 and Bax intestinal immunostaining from days 0 to 20 after transplantation were assessed.

RESULTS

Graft and patient survivals at 5 years were respectively 75% and 75% in LSbTx; 43% and 57% in SbTx (NS). Histological analysis showed higher ABC in LSbTx intestinal mucosa (P = 0.05 on day 5, P < 0.01 thereafter). Immunostaining of biopsies on day 0 after reperfusion showed different expression of NF-kB, Caspase-3 and Bax on endothelial (P < 0.05 for NF-kB and Bax), mononuclear (P < 0.05 for Bax) and epithelial cells in LSbTx and SbTx.

CONCLUSIONS

Our results suggest a protective role of the liver toward intestinal transplantation even in absence of significative difference, probably due to the small number of children. Early changes in NF-kB immunostaining in the biopsies sampled on day 0, pointed to a possible beneficial effect of the liver in the very early phase following transplantation, perhaps through the differential control of ischemia-reperfusion.

Synergistic effects of RAD and Neoral in inhibition of host-vs.-graft and graft-vs.-host immune responses in rat small-bowel transplantation

The combined effects of RAD and Neoral were tested in a rat orthotopic small-bowel transplantation model. Seven groups (n = 6) were involved in this study, and each one was included in three rejection models for the evaluation of host-vs.-graft disease (HVG) (LBN-F1 to LEW), graft-vs.-host disease (GVH) (LEW to LBN-F1), and combined HVG and GVH immune responses (BN to LEW). Both drugs were administered orally throughout the study. Low doses of RAD (1.0-2.5 mg/kg/day) combined with Neoral (2.0-5.0 mg/kg/day) produced strong synergistic effects in the prolongation of small-bowel graft survival in HVG (combination index, CI = 0.095, 0.1212), GVH (CI = 0.027, 0.020), and combined HVG and GVH immune responses (CI = 0.070, 0.301). The combination therapy of RAD and Neoral produces a strong synergistic effect toward the inhibition of HVG, GVH, and combined HVG and GVH immune responses in a rat small-bowel transplantation model.

Mortality and economics in short bowel syndrome

The incidence of patients with short-bowel syndrome (SBS) has increased over the years due to progress of intensive care medicine and parenteral nutrition techniques. These techniques have significantly improved the prognosis of neonates, children and adults who have lost major parts of their intestinal tract. Long-term survival is possible and does not depend primarily on the length of the remaining bowel but on complications such as parenteral nutrition-associated cholestasis, recurrent septicaemia, central venous catheter infections, and the motility of the remaining intestine. Thus, the overall related mortality in infants with SBS ranges from 15 to 25%, and in adults from 15 to 47%, depending on the age of the patients, the underlying disease, and the duration on total parenteral nutrition. Home parenteral nutrition (HPN) significantly decreases the complication rate and improves the psychological situation of the patient. Additionally, HPN reduces in-hospital cost significantly. Nevertheless, the annual costs/patient are between $100000 and $150000. The mortality rate of SBS patients on HPN is about 30% after 5 years, which is still lower than the 5-year survival rate of intestinal grafts, and it is about equal to patients' survival after intestinal transplantation. However, the overall costs of a successful intestinal transplantation are already lower after 2 years when compared with the cost of a prolonged HPN programme.

Natural history of intestinal failure, investigated through a national network-based approach

OBJECTIVES

Intestinal failure (IF) is a condition whose treatment requires advanced knowledge and techniques and a multidisciplinary approach. Intestinal failure is the endpoint of many intestinal diseases and may result in full recovery, in life-long parenteral nutrition, or in the death of the child. The aim of this study was to evaluate the natural history of IF in children using a national network of resources.

METHODS

Italian centers of pediatric gastroenterology merged in a national network, developing a collaborative management approach for children with IF. A consensus definition of IF was achieved. A database was set up to investigate the cause, epidemiologic factors, and natural history of IF.

RESULTS

One hundred nine children were enrolled in 5 years. The cause of IF was: short bowel syndrome (n = 48), disorders of motility (n = 16), structural enterocyte defects (n = 14), multiple food intolerance (n = 10), autoimmune enteropathy (n = 7), and others or unknown (n = 14). The eventual outcome was closely related to the primary cause, ranging from full and permanent intestinal sufficiency in children with multiple food intolerance to high death rate or total dependance upon parenteral nutrition in those with structural enterocyte defects. Intermediate outcomes were observed for the other causes. Four children received intestinal transplantation.

CONCLUSIONS

The network approach for IF provides an effective model to optimize resources and to investigate prospectively the natural history of IF. Based on the work on this series, a European network for IF could be an effective model for fulfilling the diagnostic and management needs, including intestinal transplantation.

Improved quality of life by combined transplantation in Hirschsprung's disease with a very long aganglionic segment

BACKGROUND/PURPOSE

The treatment of children with Hirschsprung's disease beginning in the proximal jejunum remains a challenge for the pediatric surgeon. These patients need a definitive parenteral nutrition, which could lead to a liver impairment. The goal of this work is to assess the quality of life after combined liver, intestine, and right colon transplantation.

METHODS

This is a retrospective study of 3 patients. Data regarding symptomatology, radiographic and operating findings, postoperating recovery, and quality of life were analyzed and compared with the quality of life before the transplantation.

RESULTS

The suspicion of a very long intestinal aganglionosis should be derived from the intestinal biopsies. Three combined liver, intestine, and right colon transplantation operations have been performed. The immunosuppression included steroids, tacrolimus, and azathioprine. An abdominal pull-trough (Duhamel procedure 2, Swenson procedure 1) was performed from 6 to 24 months after the transplantation. The follow-up after the transplantation ranges from 2 to 6 years. These 3 patients are completely off total parenteral nutrition with bowel movements 2 to 3 times a day. Two patients are continent day and night, and one is continent during the day only.

CONCLUSIONS

Intestinal transplantation is feasible with good results even when a liver impairment needs a combined intestine and liver transplantation. The right colon transplantation, in our experience, does not impair the results. The quality of life after the transplantation is better than before.

Epidemiology of invasive aspergillosis in France: a six-year multicentric survey in the Greater Paris area

Invasive aspergillosis is the most prevalent mould infection. An epidemiological surveillance network was set up in 18 teaching hospitals in Paris and the Greater Paris area. Prospective surveillance was conducted between 1994 and 1999. Between 1994 and 1997 cases were categorized as proven or probable aspergillosis and then the European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria were used. The authors analysed 621 cases (115 proven, 506 probable). No seasonal variation was found. Haematological disorders (73%) including stem-cell transplantation (36%), solid-organ transplantations (10%) and AIDS (9%) were the main underlying conditions. The crude mortality was 63%. Incidence of IA was 8% (CI(95): 6.5-9.5) in acute myelocytic leukaemia and 6.3% (CI(95): 4.3-8.3) in acute lymphocytic leukaemia. Incidence was 12.8% (CI(95): 10.8-14.8) following allogeneic stem-cell transplantation and 1.1% (CI(95): 0.7-1.5) following autologous stem-cell transplantation. In solid-organ recipients incidence ranged from 11% following heart-lung transplantation and small bowel to 0.4% following kidney transplantation. Incidence in HIV infected patients ranged from 0.02 to 0.13% per annum. This large series confirmed that patients with haematologic disorders and transplantations are the most at risk for IA.

Intestinal transplantation in pediatric patients

Intestine transplantation has evolved into a feasible alternative for children with permanent intestinal failure and life-threatening complications related to total parenteral nutrition. Although the first transplantations were done nearly 40 years ago, long-term survival has only been achieved in the last decade. Nearly 700 intestinal transplantations have been performed internationally since 1985, with an overall patient survival of greater than 50%. Improvements in patient selection, medical management, and assessment and treatment for rejection and infection have contributed to the increased survival. This article will discuss current results and medical management strategies for this innovative type of transplantation for children with end-stage short gut syndrome.

The management of patients with the short bowel syndrome

The surgeon is invariably the primary specialist involved in managing patients with short bowel syndrome. Because of this they will play an important role in co-ordinating the management of these patients. The principal aims at the initial surgery are to preserve life, then to preserve gut length, and maintain its continuity. In the immediate postoperative period, there needs to be a balance between keeping the patient alive through the use of TPN and antisecretory agents and promoting gut adaptation with the use of oral nutrition. If the gut fails to adapt during this period, then the patient may require therapy with more specific agents to promote gut adaptation such as growth factors and glutamine. If following this, the patient still has a short gut syndrome, then the principal options remain either long term TPN, or intestinal transplantation which remains a difficult and challenging procedure with a high mortality and morbidity due to rejection.

Late graft loss and long-term outcome after isolated intestinal transplantation in children

BACKGROUND/PURPOSE

The aim of this study was to determine causes of late graft loss and long-term outcome after isolated intestinal transplantation in children at a single center.

METHODS

All children who underwent primary isolated intestinal transplantation at our center with a minimum follow-up of 1 year were the subject of this retrospective study.

RESULTS

Twenty-eight children underwent primary isolated intestinal transplantation. Median graft survival was 705 days (range, 0 to 2,630 days) and median patient survival was 1,006 days (range, 0 to 2,630 days). There were 6 deaths and 15 graft losses (including the 6 nonsurvivors). Seven of the losses occurred 6 or more months after transplant. Of these, 2 losses occurred because of death of the recipients of sepsis; both recipients had functioning grafts. The 5 remaining late graft losses occurred because of acute rejection in 2 patients, chronic rejection in 2 (1 with concomitant acute rejection) and a diffuse stricturing process without the histologic hallmarks of chronic rejection in the fifth. All late survivors with intact grafts are off total parenteral nutrition (TPN).

CONCLUSIONS

Late graft loss remains a concern in a small percentage of patients after isolated intestinal transplantation. Nutritional autonomy from TPN is possible in the majority of these children after transplantation.

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.

Virtue ethics in a pluralistic world

The practice of pediatric surgery is at the crossroads of 2 specialties, pediatrics and surgery. At that vantage point, many ethical dilemmas can be seen. It is important for the pediatric surgeon to understand the special place of ethics in the care of children and how that care is influenced by society. The purpose of this report is to introduce the perspective of virtue ethics as an avenue to problem solving in ethical dilemmas in pediatric surgery. Virtue ethics relies more on the physician-focused view of character and ideal behavior as opposed to more patient-based rules of action. This ethical theory must be placed on the background of our changing society with an increasing plurality of values. The medical community of pediatric surgery must remain involved in the dialogue concerning these dilemmas in the care of children.

Small intestinal transplantation

The past few years have witnessed a considerable shift in the clinical status of intestinal transplantation. A great deal of experience has been gained at the most active centers, and results comparable with those reported at a similar stage in the development of other solid-organ graft programs are now being achieved by these highly proficient transplant teams. Rejection and its inevitable associate, sepsis, remain ubiquitous, and new immunosuppressant regimes are urgently needed; some may already be on the near horizon. The recent success of isolated intestinal grafts, together with the mortality and morbidity attendant upon the development of advanced liver disease related to total parenteral nutrition, has prompted the bold proposal that patients at risk for this complication should be identified and should receive isolated small bowel grafts before the onset of end-stage hepatic failure. The very fact that such a suggestion has begun to emerge reflects real progress in this challenging field.

Small bowel transplantation

Small bowel transplantation has become the treatment of choice for patients with chronic gut failure whose illness cannot be maintained on home parenteral nutrition. Outcomes have improved as a result of refinements in patient selection, surgical techniques, and the prevention, diagnosis, and treatment of graft rejection. Early listing is important because of the shortage of organ donors. Rejection rates are still 50% or more, despite the use of potent immune suppression. Sepsis rates are also higher for patients who have had small bowel transplantation than for those who have received other organs because of bacterial translocation from the gut secondary to preservation injury and graft rejection. Graft and patient survival rates after small bowel transplantation are comparable to rates after lung transplantation. Successful transplant recipients resume unrestricted oral diets.

Early referral is essential for successful pediatric small bowel transplantation: The Canadian experience

PURPOSE

The mortality rate for pediatric patients on the waiting list for transplantation has a major impact on the overall effectiveness of pediatric small bowel transplantation. This review was undertaken to determine the fate of Canadian children assessed for small bowel transplant and the outcome of those who undergo transplant in the tacrolimus era.

METHODS

The authors reviewed retrospectively all of the pediatric small bowel patients listed since 1988 through the Canadian Organ Replacement Register and all the children referred to our program in its first year. All children who received a small bowel transplant between January 1993 and December 1999 also were reviewed.

RESULTS

The mortality rate for pediatric patients on the small bowel transplant list was 53% after an average of 105 days on the list compared with 212 days for those who underwent transplant. Patients who died while on the list were younger and had signs of advanced liver disease at the time of listing. Thirteen Canadian children have received a small bowel transplant with an overall 1-year patient and graft survival rate of 61% and 53%, respectively. Survivors are all independent from total parenteral nutrition.

CONCLUSION

Many Canadian children miss their opportunity for a successful small bowel transplant because of late referrals and a shortage of donor organs.

Indications for pediatric intestinal transplantation: a position paper of the American Society of Transplantation

Parenteral nutrition represents standard therapy for children with short bowel syndrome and other causes of intestinal failure. Most infants with short bowel syndrome eventually wean from parenteral nutrition, and most of those who do not wean tolerate parenteral nutrition for protracted periods. However, a subset of children with intestinal failure remaining dependent on parenteral nutrition will develop life-threatening complications arising from therapy. Intestinal transplantation (Tx) can now be recommended for this select group. Life-threatening complications warranting consideration of intestinal Tx include parenteral nutrition-associated liver disease, recurrent sepsis, and threatened loss of central venous access. Because a critical shortage of donor organs exists, waiting times for intestinal Tx are prolonged. Therefore, it is essential that children with life-threatening complications of intestinal failure and parenteral nutrition therapy be identified comparatively early, i.e. in time to receive suitable donor organs before they become critically ill. Children with liver dysfunction should be considered for isolated intestinal Tx before irreversible, advanced bridging fibrosis or cirrhosis supervenes, for which a combined liver and intestinal transplant is necessary. Irreversible liver disease is suggested by hyperbilirubinemia persisting beyond 3-4 months of age combined with features of portal hypertension such as splenomegaly, thrombocytopenia, or prominent superficial abdominal veins; esophageal varices, ascites, and impaired synthetic function are not always present. Death resulting from complications of liver failure is especially common during the wait for a combined liver and intestinal transplant, and survival following combined liver and intestinal Tx is probably lower than following an isolated intestinal transplant. The incidence of morbidity and mortality following intestinal Tx is greater than that following liver or kidney Tx, but long-term survival following intestinal Tx is now at least 50-60%. It is probable that outcomes shall improve in the future with continued refinements in operative technique and post-operative management, including immunosuppression.

Pediatric short bowel syndrome: pathophysiology, nursing care, and management issues

ISSUES AND PURPOSE

A comprehensive overview of the etiology, pathophysiology, nursing care, and medical and surgical management of the child with short bowel syndrome (SBS), which follows massive anatomical or functional loss of the small intestine.

CONCLUSIONS

The outlook for children with SBS has improved due to recent advances in parenteral and enteral nutrition, pharmacologic interventions, and surgical options.

PRACTICE IMPLICATIONS

Nurses whose practice reflects an in-depth knowledge of the etiology, pathophysiology, medical and surgical management, nursing interventions, and complications of SBS will be equipped to provide quality care for children and families affected by SBS.

Overview of new immunosuppressive therapies

This review covers the new immunosuppressive drugs that have appeared in the past 5 years. It begins with the newest formulation (Neoral, Sandoz Pharmaceuticals, East Hanover, NJ, USA) of the clinically "mature" drug cyclosporin A and then reviews the literature on tacrolimus, sirolimus, and mycophenolate mofetil. In each case, the emphasis is on the evolution of experience with the drug and on the questions that the drug poses for pediatricians considering the risk-benefit ratio of the drug in children.