Infliximab as salvage therapy in paediatric intestinal transplant with steroid- and thymoglobulin-resistant late acute rejection

Living Donor Intestinal Transplantation

This study explores intestinal transplantation (ITx) as a viable treatment option for intestinal failure (IF). Historical development, donor and recipient considerations, surgical techniques, immunosuppression, and outcomes, are reviewed with particular emphasis to the value of living donor ITx. The review highlights the evolution of ITx and emphasizes the ongoing need for patient-specific selection processes. In the realm of pediatric ITx, the article underlines the significance of early intervention to mitigate IF-related liver disease. Overall, it provides a comprehensive overview of this life-saving procedure.

Immune reactions following intestinal transplantation: Mechanisms and prevention

For patients with intestinal failure, small bowel transplantation remains one of the most effective treatments despite continuous advancements in parenteral nutrition techniques. Long-term use of parenteral nutrition can result in serious complications that lead to metabolic dysfunction and organ failure. However, the small intestine is a highly immunogenic organ with a large amount of mucosa-associated lymphoid tissue and histocompatibility antigens; therefore, the small intestine is highly susceptible to severe immune rejection. This article discusses the mechanisms underlying immune rejection after small bowel transplantation and presents various options for prevention and treatment. Our findings offer new insights into the development of small bowel transplantation.

Idiopathic Ileal Ulceration After Intestinal Transplantation

Background

Idiopathic ileal ulceration after intestinal transplantation (ITx) has been discussed infrequently and has an uncertain natural history and relation to graft rejection. Herein, we review our experience with this pathology.

Methods

We retrospectively reviewed 225 ITx in 217 patients with minimum 1 y graft survival. Routine graft endoscopy was conducted up to twice weekly within the first 90 d after ITx, gradually decreasing to once yearly. Risks for ulceration over time were evaluated using Cox regression.

Results

Of 93 (41%) patients with ulcers, 50 were found within 90 d after ITx mostly via ileoscopy; delayed healing after biopsy appeared causal in the majority. Of the remaining 43 patients with ulcers found >90 d after ITx, 36 were after ileostomy closure. Multivariable modeling demonstrated within 90-d ulcer associations with increasing patient age (hazard ratio [HR], 1.027; P < 0.001) and loop ileostomy (versus Santulli ileostomy; HR, 0.271; P < 0.001). For ulcers appearing after ileostomy closure, their sole association was with absence of graft colon (HR, 7.232; P < 0.001). For ulcers requiring extended anti-microbial and anti-inflammatory therapy, associations included de novo donor-specific antibodies (HR, 3.222; P < 0.007) and nucleotide oligomerization domain mutations (HR, 2.772; P < 0.016). Whole-cohort post-ITx ulceration was not associated with either graft rejection (P = 0.161) or graft failure (P = 0.410).

Conclusions

Idiopathic ulceration after ITx is relatively common but has little independent influence on outcome; risks include ileostomy construction, colon-free ITx, immunologic mutation, and donor sensitization.

Immunosuppression Regimens for Intestinal Transplantation in Children

Pediatric intestinal transplant serves as the only definitive treatment for children with irreversible intestinal failure. Successful intestinal transplant hinges upon appropriate management of immunosuppression. The indications for intestinal transplant have changed over time. Immunosuppression regimens can be divided into induction and maintenance phases along with treatment of acute rejection. Intestinal transplant induction now often includes antithymocyte globulin or basiliximab in addition to corticosteroids. Maintenance regimens continue to be dominated by tacrolimus, with additional agents used to either decrease goal tacrolimus levels to limit toxicity or as an adjunct in sensitized patients. Careful monitoring can help to limit serious complications, such as rejection, infection, and malignancy. Future work will aim to decrease variation in practice and identify methods to determine optimal immunosuppression for a particular patient. Furthermore, there is a need for non-invasive monitoring of the intestinal graft and functional assessments of immunosuppression.

Innovations in Immunosuppression for Intestinal Transplantation

It has been 57 years since the first intestinal transplant. An increased incidence of graft rejection has been described compared to other solid organ transplants due to high immunogenicity of the bowel, which in health allows the balance between of dietary antigen with defense against pathogens. Expanding clinical experience, knowledge of gastrointestinal physiology and immunology have progress post-transplant immunosuppressive drug regimens. Current regimes aim to find the window between prevention of rejection and the risk of infection (the leading cause of death) and malignancy. The ultimate aim is to achieve graft tolerance. In this review we discuss advances in mucosal immunology and technologies informing the development of new anti-rejection strategies with the hope of improved survival in the next generation of transplant recipients.

Maintenance treatment with infliximab for ulcerative ileitis after intestinal transplantation: A case report

BACKGROUND

Evidence has been published on the successful applications of the anti-tumor necrosis factor alpha antibody infliximab, such as induction therapy, salvage treatment for acute cellular rejection, and treatment for chronic ulcerative inflammation, in intestinal transplant recipients. However, the optimal protocol for the effective use of infliximab remains largely undetermined due to scarcity of available clinical data. We report a continuative application of infliximab as maintenance therapy for recurrent chronic ulcerative ileitis in a recipient of isolated intestinal transplantation (ITx).

CASE SUMMARY

The patient was a 11-year-old boy with intestinal motility disorder classified as a hypogenic type of intestinal dysganglionosis. The patient underwent living-donor related intestinal transplant. His immunosuppression regimen consisted of daclizumab, tacrolimus, and steroids. Although he did not show rejection while on tacrolimus monotherapy, routine screening endoscopy showed several ulcerative lesions in the distal end of the graft 2 years after the intestinal transplant. Endoscopic work up to evaluate the progression of anemia revealed stenosis with ulcerative inflammatory changes and multiple longitudinal ulcers in the graft. Since the endoscopic findings suggested ulcerative lesions in Crohn’s disease, infliximab treatment was considered. Treatment with infliximab and a small dose of oral prednisolone afforded successful withdrawal of total parenteral nutrition and maintenance of a well-functioning graft without infectious complications for 5 years since the administration of the first dose of infliximab.

CONCLUSION

Infliximab is effective as maintenance therapy for recurrent chronic ulcerative ileitis in an isolated ITx patient.

The current therapeutic options for Crohn's disease: from medical therapy to intestinal transplantation

Crohn's disease (CD) has an annual incidence per 100.000 person-year of 20.2 in North America and 12.7 in Europe, and the purpose of this review is to evaluate its medical management, from diagnosis to transplant. Pharmacologic manipulation with nutritional care aims to achieve and maintain remission, but more than half of patients will undergo an intestinal resection, very often repeated over time. They could experience short bowel syndrome (SBS) requiring total parenteral nutrition (TPN). Intestinal transplantation (ITx) represents an alternative in case of irreversible intestinal failure (IF) with life-threatening TPN complications. Patient survival after ITx is 79%, 53% and 43% at 1, 3 and 5 years respectively, with no differences among ITx for other disorders. Areas covered: The research discussed medical therapy with nutritional support, evaluating the role of endoscopy, surgery and transplant in CD. A systematic literature review was conducted using the PubMed search engine up to May 31^th, 2017 without restriction of the language. The decision on paper's eligibility was reached by consensus between the 3 screening authors. Expert commentary: CD treatment is mainly medical, leaving endoscopy and surgery for a complex course. ITx represents a therapeutic option if TPN complications with IF arise.

Advances in small bowel transplantation

Small bowel transplantation is a life-saving surgery for patients with intestinal failure. The biggest problem in intestinal transplantation is graft rejection. Graft rejection is the main reason for morbidity and mortality. Rejection has a negative effect on the survival of the graft. While 50%-75% of small bowel transplantation patients experience acute rejection, chronic rejection occurs in approximately 15% of patients. Immune monitoring is crucial after small bowel transplantation. Unlike other types of transplantation, there are no non-invasive or reliable markers to predict rejection in small bowel transplantation. The diagnosis of AR is confirmed by clinical symptoms, endoscopic appearance, and pathological specimens taken by endoscopy. Thus, histopathological examinations obtained by protocol biopsies remain as the gold standard for intestinal graft monitoring; however, biopsies have some complications, especially in small grafts. In addition to the high complication rate, biopsies are non-diagnostic; thus, multiple biopsies should be performed to exclude rejection. Therefore, auxiliary assays, such as measurements of citrulline and calprotectin in the blood, cytofluorographic examination of peripheral blood immune cells, cytokine profiling, and distinct gene-set-change measurements, are increasingly being used in small bowel transplantation. Developments in the understanding of genes seem to be promising that limited gene sets, taken from blood or from intestinal biopsies, will enhance pathological diagnosis. Bone marrow mesenchymal stem cell transplantation with SBT and tissue engineering are also promising procedures.

Impacts of donor-specific anti-HLA antibodies and antibody-mediated rejection on outcomes after intestinal transplantation in children

AMR is a risk factor for graft failure after SBTx. We studied impact of DSAs and AMR in 22 children transplanted between 2008 and 2012 (11 isolated SBTx, 10 liver inclusive Tx, and one modified multivisceral Tx). Three patients never developed DSA, but DSAs were found in seven in the pre-Tx period and de novo post-Tx in 19 children. Pathology revealed cellular rejection (15/19), with vascular changes and C4d+. Patients were treated with IV immunoglobulins, plasmapheresis, and steroids. Rescue therapy included antithymocyte globulins, rituximab, eculizumab, and bortezomib. Pathology and graft function normalized in 13 patients, graft loss occurred in two, and death in seven. At the end of the follow-up, 15 children were alive (68%), 13 with functioning graft (59%). Prognosis factors for poor outcome after Tx were the presence of symptoms at AMR suspicion (P +.033). DSAs were often found following SBTx, mostly de novo. Resistant ACR or severe AMR is still difficult to differentiate, with a high need for immunosuppression in both. DSAs may precede development of severe disease and pathology features on the graft: relationship and correlation need to be better investigated with larger groups before and after Tx.

The role of biologicals in intestinal transplantation

PURPOSE OF REVIEW

This article reviews the role of biologicals in intestinal transplantation.

RECENT FINDINGS

Several biologicals have been used in intestinal and multivisceral transplantation for various indications, such as induction therapy, prevention and treatment of antibody-mediated rejection, desensitization, anti-inflammatory treatment, as well as treatment of Epstein-Barr virus-associated posttransplant lymphoproliferative disease. Particularly, the administration of biologicals in induction therapy such as T-cell depleting antibodies and interleukin-2 receptor antagonists have significantly contributed to the great improvement of patient and allograft outcome. Novel biologicals, such as B-cell, plasma-cell, and complement-directed agents have been successfully applied to treat antibody and complement-driven alloimmune processes to stabilize long-term outcome. Several other inflammatory allotransplant conditions have been addressed with anti-TNF-α antibodies, such as infliximab.

SUMMARY

Biologicals have contributed significantly to the recent success of intestinal transplantation. Novel developments in this field are supposed to aid in addressing various urgent needs in intestinal transplantation, such as preimmunization, antibody and complement-induced graft injury, as well as pathologies originating from innate immune responses.

Intestinal transplantation in children: current status

Intestinal transplantation (IT) is the least common form of organ transplantation; however, it has shown exceptional growth and improvement in graft survival rates over the past two decades mainly due to better outcomes achieved during the first year of transplantation (76 % at 1 year), due to improvement in surgical techniques and the development of better immunosupressive therapies as we understand more about the relationship between the recipient and host immune system. There are still ongoing issues with chronic rejection and long-term survival. Intestinal transplantation is still an acceptable therapy for patients with intestinal failure (IF), but it is generally reserved for patients who develop severe and life-threatening complications despite standard therapies, or those who are not able to maintain a good quality of life. The purpose of this review is to describe the current status, indications, outcomes and advances in the field of intestinal transplantation.

The current state of intestine transplantation: indications, techniques, outcomes and challenges

Intestine transplantation is the least common form of organ transplantation in the United States and often deemed one of the most difficult. Patient and graft survival have historically trailed well behind other organ transplants. Over the past 5-10 years registry reports and single center series have demonstrated improvements to patient survival after intestinal transplantation that now match patient survival for those without life-threatening complications on parenteral nutrition. For various reasons including improvements in medical care of patients with intestinal failure and difficulty accessing transplant care, the actual number of intestine transplants has declined by 25% over the past 6 years. In light of the small numbers of intestine transplants, many physicians and the lay public are often unaware that this is a therapeutic option. The aim of this review is to describe the current indications, outcomes and advances in the field of intestine transplantation and to explore concerns over future access to this important and life-saving therapy.

Chronic mucosal inflammation/inflammatory bowel disease-like inflammation after intestinal transplantation: where are we now?

PURPOSE OF REVIEW

The purpose of this review is to highlight the similarities between inflammatory bowel disease and the state of the intestine allograft after transplantation.

RECENT FINDINGS

The mutant nucleotide-binding oligomerization protein 2 (NOD2) gene, which encodes for an intracellular protein that serves as an innate immune system microbial sensor in macrophages, dendritic cells, and certain intestinal epithelial cells, has been recognized as a risk factor in Crohn's disease. Similarly, recent studies have also highlighted the contribution the NOD2 mutation may have on intestinal failure itself. More specifically, in intestinal transplant recipients with the NOD2 mutation, the discovery of the reduced ability to prevent bacterial clearance, increased enterocyte stress response, and failure of key downstream expression of important cytokines and growth factors have been implicated as major factors in intestinal transplant outcomes, namely graft loss and septic death. Treatment strategies with anti tumor necrosis factor (TNF) α, similar to inflammatory bowel disease, have been employed in intestinal transplantation with promising results.

SUMMARY

In intestinal transplantation, there is evidence that the classical alloimmunity pathways that lead toward graft dysfunction and eventual graft loss may, in fact, be working in concert with a disordered innate immune system to produce a state of chronic inflammation not unlike that seen in inflammatory bowel disease.