Current status of small bowel transplantation in children: update 2003

Surveillance of Rejection After Intestinal Transplantation Using an Image Enhanced Endoscopy "VENCH" Scoring System

BACKGROUND

Graft rejection after intestinal transplantation remains challenging. We aimed to use endoscopy for rejection prediction.

MATERIALS AND METHODS

Patients ≥7 years old who underwent intestinal transplantation between November 2016 and September 2019 were prospectively enrolled. Magnifying endoscopy under narrow-band imaging was performed through ileostomy. Endoscopic findings were reported as five components (each graded from 0-2): "V" (villi appearance), "E" (erythema), "N" (capillary network), "C" (crypt widening), and "H" (heterogeneity). The correlation between histological severity and endoscopic score was analyzed.

RESULTS

Ninety-nine endoscopic biopsies from three female and one male patient were analyzed. The mean ± SD age was of 41.25±13.77 (range 29-58) years. Three short bowel syndrome patients after multiple intestinal resections and one with chronic intestinal pseudo-obstruction were indicated for intestinal transplantation. Sensitivity, specificity, and accuracy of V, E, N, C, and H scores for predicting rejection were 97.4%, 45.9%, 65.7%; 94.7%, 70.5%, 79.8%; 97.4%, 52.5%, 69.7%; 94.7%, 54.1%, 69.7%; and 97.4%, 62.3%, 75.8%, respectively. Pearson's correlation coefficients between total and individual V, E, N, C, H scores and histological rejection were 0.79, 0.64, 0.70, 0.71, 0.73, and 0.66, respectively (P < .001). To predict mild and moderate/severe rejection, total scores more than 4 and 6 had the sensitivity/specificity of 87.50%/57.38% and 96.67%/85.25%, respectively (area under the ROC 0.791 and 0.987).

CONCLUSION

Endoscopic VENCH scoring is promising for predicting rejection after IT. More studies are warranted to validate such results. (ClinicalTrials.gov number, NCT03616548.).

Parenteral Nutrition-Associated Cholestasis Related to Parental Care

Parenteral nutrition-associated cholestasis (PNAC) is a complication not uncommon in the pediatric population. In severe cases, patients require a liver transplant. To our knowledge, we report the only case of PNAC with end-stage liver failure in a child with short bowel syndrome that resolved with a change in caretaker. Until his care was transferred from his abusive parents, he was frequently admitted for infection and sepsis. His liver function vastly improved from aspartate aminotransferase (AST) 3139 units/L, conjugated bilirubin 25.9 mg/dL to AST 47 units/L, direct bilirubin 0.3 mg/dL under the care of his attentive foster mother, and a liver transplant was no longer necessary. Bacterial infection and sepsis are risk factors correlated with patients with PNAC requiring liver transplant. Prevention of infection by a good caregiver may be a means to reduce the incidence of PNAC.

An Analysis of the Long-Term Complications of Intestine Transplant Recipients

Background

One-year survival rates for intestine transplant recipients have increased to 70%, but it is believed that the complications following the procedure do not diminish after the first year as is seen in other forms of solid-organ transplantation.

Objective

To review the ongoing medical requirements of an increasing number of long-term survivors of intestinal transplantation.

Method

A retrospective medical chart review was completed on all patients who received intestinal transplantation at the University of Nebraska Medical Center from September 1990 through March 2003. One hundred forty-six transplantations were performed on 128 patients—53 intestinal, 70 liver/intestinal, and 23 intestinal with liver and pancreas or kidney.

Results

Seventy-six patients survived longer than 365 days and form the study group. Major reasons for readmissions were infections, gastrointestinal complications, dehydration, and rejection. The average number of rehospitalizations per patient per year remained constant. Death in patients with more than 365 days survival (N=23) was the result of sepsis (56%) and multiple other complications (44%).

Conclusion

The number of readmissions each year per patient remains constant and medical problems remain complex and life threatening. Patients with intestinal transplantation will continue to require regular expert follow-up care and careful attention to even the smallest medical problem even years following transplantation.

Nationwide survey on adult type chronic intestinal pseudo-obstruction in surgical institutions in Japan

BACKGROUND

No appropriate management of chronic intestinal pseudo-obstruction (CIP) has been established.

PATIENTS AND METHODS

The clinicopathological parameters of 103 cases collected by a nationwide questionnaire study were reviewed.

RESULTS

The CIP cases were primary in 86 (83%) cases and secondary in 15 (15%) cases. The age of onset of the primary type was significantly younger than that of the secondary type (p = 0.011). The diseased segments of the bowel were the large bowel in 60 (58%), the small bowel in 17 (17%), and both in 23 (22%) cases, respectively. Abdominal distension and pain were common symptoms regardless of the types of the diseased bowel; however, constipation was frequently seen in the large bowel type (p = 0.0258). Vomiting and diarrhea were seen with marginally higher frequency in the small bowel type (p = 0.0569, 0.0642). Surgical treatment was most effective in the large bowel type, less effective in the small bowel type, and least effective in the large and small bowel type. The prognosis of the primary CIP was significantly better than that of the secondary CIP (p = 0.033).

CONCLUSIONS

The segments of the diseased bowels should be considered in determining the indications for surgical treatments in CIP patients.

Diagnosis and management of intestinal motility disorders

Gastrointestinal motility disorders in their most severe forms may directly lead to intestinal failure. Abnormal motor function may also contribute to the overall gut dysfunction of children who have other underlying gastrointestinal diseases, such as Hirschsprung disease or gastroschisis. Understanding the extent and the severity of the dysmotile segments has direct therapeutic and prognostic implications. Our ability to study gastrointestinal motility has greatly improved in the past few years, with the development of less-invasive diagnostic tests. Optimal treatment of children with intestinal motility disorders relies on a multidisciplinary approach, which focuses on optimizing nutrition, improving gastrointestinal motility, and reducing psychosocial disability. Patient education is important to avoid aggravations of symptoms caused by dietary indiscretions.

Clinical report--Forgoing medically provided nutrition and hydration in children

There is broad consensus that withholding or withdrawing medical interventions is morally permissible when requested by competent patients or, in the case of patients without decision-making capacity, when the interventions no longer confer a benefit to the patient or when the burdens associated with the interventions outweigh the benefits received. The withdrawal or withholding of measures such as attempted resuscitation, ventilators, and critical care medications is common in the terminal care of adults and children. In the case of adults, a consensus has emerged in law and ethics that the medical administration of fluid and nutrition is not fundamentally different from other medical interventions such as use of ventilators; therefore, it can be forgone or withdrawn when a competent adult or legally authorized surrogate requests withdrawal or when the intervention no longer provides a net benefit to the patient. In pediatrics, forgoing or withdrawing medically administered fluids and nutrition has been more controversial because of the inability of children to make autonomous decisions and the emotional power of feeding as a basic element of the care of children. This statement reviews the medical, ethical, and legal issues relevant to the withholding or withdrawing of medically provided fluids and nutrition in children. The American Academy of Pediatrics concludes that the withdrawal of medically administered fluids and nutrition for pediatric patients is ethically acceptable in limited circumstances. Ethics consultation is strongly recommended when particularly difficult or controversial decisions are being considered.

Transplantation of the spleen: effect of splenic allograft in human multivisceral transplantation

OBJECTIVES

To describe the effect of the splenic allograft in human multivisceral transplantation.

SUMMARY BACKGROUND DATA

We performed transplants of the spleen as part of a multivisceral graft in an attempt to decrease both the risk of infection from an asplenic state and the risk of rejection by a possible tolerogenic effect. To our knowledge, this is the first report of human splenic transplantation in a large series.

METHODS

All primary multivisceral recipients who received a donor spleen (N = 60) were compared with those who did not receive a spleen (N = 81).

RESULTS

Thirty-five of 60 (58%) are alive in the spleen group, and 39 of 81 (48%) are alive in control group (P = 0.98). In univariate analysis, splenic recipients showed superiority in freedom-from-any rejection (P = 0.02) and freedom-from-moderate or severe rejection (P = 0.007). No significant differences were observed in analyses of infectious complications between the spleen and control groups. Both platelet and leukocyte counts became normal in splenic patients, whereas these counts were significantly increased in nonsplenic recipients. Observed incidence of graft versus host disease (GVHD) was 8.25% (5 of 60) in the spleen group and 6.2% (5 of 81) in the control group (P = 0.70). Increased incidence of autoimmune hemolysis was observed in the spleen group.

CONCLUSIONS

Allograft spleen can be transplanted within a multivisceral graft without significantly increasing the risk of GVHD. The allogenic spleen seems to show a protective effect on small bowel rejection. Further investigation with longitudinal follow-up is required to precisely determine the immunologic and hematologic effects of the allograft spleen.

Prevention of catheter-related bacteremia in pediatric intestinal transplantation/short gut syndrome children with long-term central venous catheters

Catheter-related bacteremia (CRB), along with liver failure is the leading cause of mortality and morbidity in parenteral nutrition dependent children. Immunosuppressant therapy following transplantation increases the risk of CRB. Previous reports in pediatric cancer patients have described the use of antibiotic lock solutions (ABL) for prophylaxis of CRB. In our institution, we evaluated five children (ages between one and four yr old), three with intestinal transplantation and two with short gut syndrome, who were high risk for recurrent CRB defined by their incidence of bacteremias in the observation period (>2 CRB/six months or life-threatening CRB). These children received the prophylactic ABL protocol with tobramycin-tissue plasminogen activator, four h per day, on alternating ports for six to eight months. Each patient was his/her own historical control. We observed decreased incidence of CRB's (p < 0.05), days of hospitalization due to CRB's (p < 0.0001), the days of intensive care admissions due to CRB (p < 0.0001), as well as the total days of systemic antibiotic exposure (p < 0.001). Catheter survival during the ABL era was longer but not reaching statistical significance. There was no advantage in removing and later replacing the catheter to wire-guided exchange while on systemic antibiotics. One patient presented with break-through bacteremia, septic shock and died. None of the catheters were lost to occlusion/malfunction. ABL did not induce an increased resistance to tobramycin. These preliminary findings suggest that ABL can be used safely and effectively in parenteral nutrition dependent children with long-term central venous catheters.

Intestinal transplantation for short bowel syndrome secondary to gastroschisis

BACKGROUND/PURPOSE

Gastroschisis is the most frequent cause of pediatric intestinal transplantation. This study reviews our experience of intestinal transplantation secondary to gastroschisis to elucidate those factors affecting the outcome of children with short bowel syndrome.

METHODS

A retrospective review was performed for children who underwent intestinal transplantation for gastroschisis at the University of Miami between June 2003 and August 1994.

RESULTS

Thirty-two transplants were performed in 28 children with gastroschisis during the study period. Associated intestinal anomalies were present in 22 infants (atresia [n = 14], volvulus [n = 3], and/or ischemia [n = 16]). Spontaneous prenatal closure of gastroschisis, a rare anomaly associated with bowel atresia and ischemia because of a very small abdominal defect, was seen in 9 patients. Most of the patients had a complicated course and required multiple abdominal surgeries before transplant. Fifteen (53.6%) patients are currently alive at a median follow-up of 23.5 months. Short-term survival rate has significantly improved in recent years.

CONCLUSIONS

Patients with complex gastroschisis and intestinal anomalies have a significant risk for progression to short bowel syndrome. Intestinal transplantation can be a lifesaving option and provides a satisfactory outcome for children with short bowel syndrome secondary to gastroschisis.

Zoom endoscopic monitoring of small bowel allograft rejection

BACKGROUND

The small bowel has been successfully transplanted in patients with irreversible intestinal failure. This report aims to describe endoscopic monitoring of small bowel rejection.

METHODS

A magnification endoscope (zoom endoscope) was used in this study. In the first part of the study (October 1998 to March 2000, 271 endoscopy sessions), the specific endoscopic findings that correlated with rejection were determined. An analysis then was performed on data from the second period (March 2001 to November 2002, 499 sessions) to evaluate the zoom endoscope's accuracy in monitoring rejection.

RESULTS

Specific endoscopic findings of rejection found in the first period included background erythema, villous congestion, blunted villous tip, and shortened villous height. When the rejection was successfully treated, endoscopic appearance returned to normal. On the basis of these findings, five endoscopic criteria (villous shortening, villous blunting, background erythema, villous congestion, and mucosal friability) were used to score endoscopic sessions in the second period. Endoscopic diagnosis of rejection was compared with histology. Adult patients showed a sensitivity of 45%, a specificity of 98%, a positive predictive value of 82%, and a negative predictive value of 88%. In pediatric patients, these values were, respectively, 61%, 84%, 57%, and 86%. On 59 distinct occasions (30 in period 1 and 29 in period 2) in which the results were endoscopy negative yet biopsy positive (mild) for rejection, we elected not to treat these rejections on the basis of clinical evaluation, and 58 (98%) resolved without further therapy.

CONCLUSIONS

With the use of magnification, endoscopy is a useful tool for monitoring acute rejection in the small bowel allograft.

Gastrointestinal tract ulcers in pediatric intestinal transplantation patients: etiology and management

One of the observed complications in patients after intestinal transplantation is the occurrence of ulcers in the native or transplanted gastrointestinal tract. Previous reports have described the appearance of ulcers but have not described any systemic approach to accurately diagnose the etiology of the ulcer. We evaluated 112 intestinal transplantation patients at our institution, in which endoscopic examination identified ulcer formation in 11 patients. No common or defining demographic or clinical variables were found in the patients with ulcers. Biopsies were obtained from the ulcer edge as well as the intervening mucosa. The most common changes in the ulcers were compatible with post-transplant lymphoproliferative disorder (PTLD), acute rejection, and viral infections. These changes could occur simultaneously and retrospective analysis showed that ulcers could have concomitant etiologies. Endoscopically directed biopsies of ulcer edges often displayed morphologic changes compatible with acute rejection of the graft. Some patients were treated for rejection based on the changes within the mucosa outside the ulcer bed, and they responded with resolution of the ulcers. Our findings demonstrate that PTLD and acute rejection are the most common causes of chronic ulcer formation and reinforce the concept that biopsy samples should be collected simultaneously from both the ulcer edge and intervening mucosa.

Anastomotic ulceration following small bowel transplantation

We describe, for the first time, anastomotic ulcers (AU) following bowel transplantation at the Hospital for Sick Children. Two children presented with rectal bleeding, 6 and 9 months, following the transplantation. Isolated ulcers were identified at the ileo-colonic and the colo-colonic anastomosis site. The ulcers resolved, but recurred 6 and 7 months after the initial presentation. Both patients were positive for adenovirus in the stool and were treated with rapamycin. The histology revealed granulation tissue formation with mild inflammation in the adjacent mucosa, without evidence of rejection or infection. A literature search revealed 10 studies reporting 29 patients who developed AU following various surgical etiologies, none of which was bowel transplant. Numerous factors that are unique to the post-transplant period may predispose to such ulcer and are discussed in detail. Physicians and surgeons should be aware of this multifactorial complication, among other etiologies, as a cause of anemia or rectal bleeding following intestinal transplantation.

A history of pediatric critical care medicine

Critical care medicine developed out of other subspecialties' need to provide care for their most critically ill patients. Advanced technologies, the understanding of the pathophysiology of critical illness, and the development of the multidisciplinary team have made this care possible. Pediatric critical care medicine emerged in the 1960s and has expanded dramatically since then. The field has made major advances in the areas of lung injury, sepsis, traumatic brain injury, and postoperative care. We review here the evolution of modern pediatric critical care medicine from its roots in general pediatric and cardiac surgery, adult respiratory care medicine, neonatology, and pediatric anesthesiology to its current state as a unique discipline.

Analysis of vascular access in intestinal transplant recipients using the Miami classification from the VIIIth International Small Bowel Transplant Symposium

BACKGROUND

Loss of vascular access in patients with intestinal failure is considered an indication for intestinal transplantation. Such patients often have one or more occluded vein sites. Venous access could be classified according to the number of occluded vessels, to facilitate pre- and postoperative management.

METHODS

At the VIIIth International Small Bowel Transplant Symposium in September 2003, a new classification of vascular access in patients who were candidates for bowel transplant was proposed. The classification was then applied to stratify all patients that underwent intestinal transplantation at the University of Miami between 1998 and 2003. Data were collected on Doppler ultrasonography, angiography, and vein angioplasty in such patients.

RESULTS

A total of 106 cases in 91 patients were included in the study. Based on Doppler ultrasound results, 51.9% of patients fell into class I (no thrombosed vessels), 21.7% were in class II (one occluded vessel, or positive risk factors for thrombosis), 24.5% were in class III (multiple thrombosed vessels), and 1.9% were in class IV (all vessels thrombosed). Fifteen percent of the patients required preoperative angiography to better evaluate venous access. Most of the patients that required angiography were in class III or IV, and 53.3% of patients requiring angiography needed additional venous angioplasty to achieve access.

CONCLUSIONS

All patients that are referred for intestinal transplantation should undergo preliminary mapping of their venous access by Doppler ultrasound and then be assigned to a vascular access class. Those patients with multiple thrombosed vessels (class III and above) should be strongly considered for additional angiographic evaluation.

Biological and psychological differences in the child and adolescent transplant recipient

Solid organ transplantation has become accepted therapy for the treatment of end-stage organ dysfunction in children. As early management of the pediatric transplant recipient has improved, important age-related differences in long-term patient outcomes have become apparent. Late morbidity and mortality can, in most cases, be attributed to the consequences of long-term immunosuppression: graft loss from under-immunosuppression or an increased incidence of cancer, hypertension, renal failure or diabetes from over-immunosuppression. Age-related differences in both biological and psychological factors play an important role in the optimization of therapy in the transplanted child. Important age-related differences have been demonstrated in all phases of pharmacokinetics: absorption, distribution, metabolism and elimination. Information regarding specific age-related pharmacokinetic differences is lacking for many immunosuppressive medications. Further study using physiologically based pharmacokinetic (PBPK) models will lead to more specific recommendations for age-based immunosuppression protocols. Non-adherence is common among solid organ transplant recipients of all ages and the consequences of non-adherence include increased rejection, late graft loss and death. The biological and psychological developmental changes that occur during adolescence place the transplanted adolescent at an even higher risk of non-adherence and poor outcome than other age groups. Further studies to elucidate the importance of both age-related pharmacokinetic and behavioral factors are needed to formulate therapeutic interventions that would improve adherence and patient outcomes.

Gene expression profile in rat small intestinal allografts after cold preservation/reperfusion

AIM: To determine the changes of gene expression profile in small intestinal allografts in rats after cold preservation/reperfusion, and to identify the genes relevant to cold preservation/reperfusion injury.

METHODS: Heterotopic segmental small bowel transpla-ntation was performed in six rats with a sham operation and they were used as controls. Total RNA was extracted from the allografts (experimental group) and normal intestines (control group) 1 h after cold preservation/reperfusion, and then purified to mRNA, which was then reversely transcribed to cDNA, and labeled with fluorescent Cy5-dUTP and Cy3-dUTP to prepare hybridization probes. The mixed probes were hybridized to the cDNA microarray. After high-stringent washing, the fluorescent signals on cDNA microarray chip were scanned and analyzed.

RESULTS: Among the 4 096 target genes, 82 differentially expressed genes were identified between the two groups. There were 18 novel genes, 33 expression sequence tags, and 31 previously reported genes. The selected genes may be divided into four classes: genes modulating cellular adhesion, genes regulating cellular energy, glucose and protein metabolism, early response genes and other genes.

CONCLUSION: A total of 82 genes that may be relevant to cold preservation/reperfusion injury in small intestinal allografts are identified. Abnormal adhesion between polymorphonuclears and endothelia and failure in energy, glucose and protein metabolism of the grafts may contribute to preservation/reperfusion injury. The functions of the novel genes identified in our study need to be clarified further.

Intestinal transplantation in children: a summary of clinical outcomes and prognostic factors in 108 patients from a single center

We performed 124 intestinal transplants on 108 children (median age, 1.5 years) since 1994. Initial graft types included isolated intestine (I) (n=26), liver and intestine (LI) (n=26), multivisceral (MV) (n=50), and multivisceral without liver (MMV) (n=6). Four groups were defined by type of induction therapy: none, OKT3, or cyclophosphamide (August 1994-December 1997, n=25), early experience with daclizumab (January 1998-December 2000, n=26), recent experience with daclizumab (January 2001-April 2004, n=40), and Campath-1H (January 2001-April 2004, n=17). Actuarial patient survival at 1 year for groups 1-4 was 44%+/-10%, 54%+/-10%, 83%+/-6%, and 41%+/-12%, respectively, with group 3 having the most favorable survival (P=0.0004). Using Cox stepwise regression, the hazard rate of developing severe rejection was significantly higher in patients with transplant type I or LI (P=0.0002), with no difference between these groups (P=0.24) but a significantly higher rate for LI versus MV (P=0.005). Three factors associated with improved patient survival were recipient of MV or MMV (P=0.008), age at transplantation greater than 1 year (P=0.01), and use of daclizumab (P=0.0006). Cause-specific hazard analysis revealed a decreased rate of rejection-related mortality for recipients of MV or MMV (P=0.0007), whereas age greater than 1 year indicated a lower rate of infection-related mortality (P=0.0009). Pediatric intestinal transplantation provides an increasingly realistic chance of survival, particularly with the more recent use of daclizumab and multivisceral transplantation. A protective effect of multivisceral transplantation appears to exist with respect to the development of severe rejection.