Evaluation of pediatric patients for intestinal transplantation in the modern era.

OBJECTIVES: To review recent evaluations of pediatric patients with intestinal failure (IF) for intestinal transplantation (ITx), waiting list decisions, and outcomes of patients listed and not listed for ITx at our center. METHODS: Retrospective chart review of 97 patients evaluated for ITx from January 2014 to December 2021 including data from referring institutions and protocol laboratory testing, body imaging, endoscopy, and liver biopsy in selected cases. Survival analysis used Kaplan-Meier estimates and Cox proportional hazards regression. RESULTS: Patients were referred almost entirely from outside institutions, one-third because of intestinal failure-associated liver disease (IFALD), two-thirds because of repeated infective and non-IFALD complications under minimally successful intestinal rehabilitation, and a single patient because of lost central vein access. The majority had short bowel syndrome (SBS). Waiting list placement was offered to 67 (69%) patients, 40 of whom for IFALD. The IFALD group was generally younger and more likely to have SBS, have received more parenteral nutrition, have demonstrated more evidence of chronic inflammation and have inferior kidney function compared to those offered ITx for non-IFALD complications and those not listed. ITx was performed in 53 patients. Superior postevaluation survival was independently associated with higher serum creatinine (hazard ratio [HR] 15.410, p = 014), whereas inferior postevaluation survival was associated with ITx (HR 0.515, p = 0.035) and higher serum fibrinogen (HR 0.994, p = 0.005). CONCLUSIONS: Despite recent improvements in IF management, IFALD remains a prominent reason for ITx referral. Complications of IF inherent to ITx candidacy influence postevaluation and post-ITx survival.

Non-fatal outcomes of COVID-19 disease in pediatric organ transplantation associates with down-regulation of senescence pathways.

This is a cross-sectional study examining kinetics and durability of immune response in children with solid organ transplants (SOTs) who had COVID-19 disease between November 2020 through June 2022, who were followed for 60-days at a single transplant center. Blood was collected between 1-14 (acute infection), and 15-60 days of a positive PCR (convalescence). SOT children with peripheral blood mononuclear cells (PBMC) cryopreserved before 2019 were non-infected controls (ctrls). PBMCs stimulated with 15-mer peptides from spike protein and anti-CD49d/anti-CD28. Testing done included mass cytometry, mi-RNA sequencing with confirmatory qPCR. 38 children formed the study cohort, 10 in the acute phase and 8 in the convalescence phase. 20 subjects were non-infected controls. Two subjects had severe disease. Subjects in the acute and convalescent phases were different subjects. The median age and tacrolimus level at blood draw was not significantly different. There was no death, and no subject was lost to follow-up. During acute infection CD57 expression was low in NKT, Th17 effector memory, memory Treg, CD4-CD8-, and γδT cells (p = 0.01, p = 0.04, p = 0.03, p = 0.03, p = 0.004 respectively). The frequencies of NK and Th2 effector memory cells increased (p = 0.01, p = 0.02) during acute infection. Non-switched memory B and CD8 central memory cell frequencies were decreased during acute infection (p = 0.02; p = 0.02), but the decrease in CD8 central memory cells did not persist. CD4-CD8- and CD14 monocyte frequencies increased during recovery (p = 0.03; p = 0.007). Our observations suggest down regulation of CD57 with absence of NK cell contraction protect against death from COVID-19 disease in children with SOTs.

Outcomes of Portosystemic Shunts in Children with and without Liver Transplantation.

Purpose: Limited data exist regarding outcome and morbidity associated with portosystemic shunts in the pediatric transplant population. Our study assesses the outcomes of pediatric patients who underwent a portosystemic shunt procedure, both with and without liver transplantation (LT). Methods: This study retrospectively reviewed the medical records of pediatric patients aged 0-19 years who underwent shunt placement between 2003 and 2017 at a tertiary care center. The analysis included cases of shunt placement with or without LT. Results: A total of 13 pediatric patients were included in the study with median age of 8.8 years. Among the cases, 11 out of 13 (84.6%) underwent splenorenal shunt, 1 (7.7%) underwent a mesocaval shunt, and another 1 (7.7%) underwent a Modified Rex (mesoportal) shunt. Additionally, 5 out of 13 (38.5%) patients had LT, with 4 out of 5 (80.0%) receiving the transplant before shunt placement, and 1 out of 5 (20.0%) receiving it after shunt placement. Gastrointestinal bleeding resulting from portal hypertension was the indication in all cases. A total of 10 complications were reported in 5 patients; the most common complication was anemia in 3 (23.1%) patients. At the most recent follow-up visit, the shunts were functional without encephalopathy, and no deaths were reported. Conclusion: Shunt placement plays a crucial role in the management of patients with portal hypertension. Our study demonstrates favorable long-term outcomes in pediatric patients who underwent shunt placement. Long term shunt outcomes were similar and unremarkable in patients with LT and without LT.

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.

COVID-19 Disease in Pediatric Solid Organ Transplantation from Alpha to Omicron: A High Monocyte Count in the Preceding Three Months Portends a Risk for Severe Disease.

IMPORTANCE: Planning for future resurgences in SARS-CoV-2 infection is necessary for providers who care for immunocompromised patients. OBJECTIVE: to determine factors associated with COVID-19 disease severity in immunosuppressed children. DESIGN: a case series of children with solid organ transplants diagnosed with SARS-CoV-2 infection between 15 March 2020 and 31 March 2023. SETTING: a single pediatric transplant center. PARTICIPANTS: all children with a composite transplant (liver, pancreas, intestine), isolated intestine transplant (IT), isolated liver transplant LT), or simultaneous liver kidney transplant (SLK) with a positive PCR for SARS-CoV-2. EXPOSURE: SARS-CoV-2 infection. MAIN OUTCOME AND MEASURES: We hypothesized that children on the most immunosuppression, defined by the number of immunosuppressive medications and usage of steroids, would have the most severe disease course and that differential white blood cell count in the months preceding infection would be associated with likelihood of having severe disease. The hypothesis being tested was formulated during data collection. The primary study outcome measurement was disease severity defined using WHO criteria. RESULTS: 77 children (50 LT, 24 intestine, 3 SLK) were infected with SARS-CoV-2, 57.4 months from transplant (IQR 19.7-87.2). 17% were ≤1 year post transplant at infection. 55% were male, 58% were symptomatic and ~29% had severe disease. A high absolute lymphocyte count at diagnosis decreased the odds of having severe COVID-19 disease (OR 0.29; CI 0.11-0.60; p = 0.004). Conversely, patients with a high absolute monocyte count in the three months preceding infection had increased odds of having severe disease (OR 30.49; CI 1.68-1027.77; p = 0.033). Steroid use, higher tacrolimus level, and number of immunosuppressive medications at infection did not increase the odds of having severe disease. CONCLUSIONS AND RELEVANCE: The significance of a high monocyte count as predictor of severe disease potentially confirms the importance of monocytic inflammasome-driven inflammation in COVID-19 pathogenesis. Our data do not support reducing immunosuppression in the setting of infection. Our observations may have important ramifications in resource management as vaccine- and infection-induced immunity wanes.

Impaired Cellular and Antibody immunity after COVID-19 in Chronically Immunosuppressed Transplant Recipients.

Assessment of cellular immunity to the SARS-CoV-2 coronavirus is of great interest in chronically immunosuppressed transplant recipients (Tr), who are predisposed to infections and vaccination failures. We evaluated CD154-expressing T-cells induced by spike (S) antigenic peptides in 204 subjects-103 COVID-19 patients and 101 healthy unexposed subjects. S-reactive CD154+T-cell frequencies were a) higher in 42 healthy unexposed Tr who were sampled pre-pandemic, compared with healthy NT (p=0.02), b) lower in Tr COVID-19 patients compared with healthy Tr (p<0.0001) and were accompanied by lower S-reactive B-cell frequencies (p<0.05), c) lower in Tr with severe COVID-19 (p<0.0001), or COVID-19 requiring hospitalization (p<0.05), compared with healthy Tr. Among Tr with COVID-19, cytomegalovirus co-infection occurred in 34%; further, incidence of anti-receptor-binding-domain IgG (p=0.011) was lower compared with NT COVID-19 patients. Healthy unexposed Tr exhibit pre-existing T-cell immunity to SARS-CoV-2. COVID-19 impairs anti-S T-cell and antibody and predisposes to CMV co-infection in transplant recipients.

SARS-CoV-2 Infection in Pediatric Solid Organ Transplant Recipients: A Single Center Observation.

OBJECTIVES: This is a descriptive study to characterize rates of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in pediatric solid organ transplant (SOT) recipients during the early days of the pandemic. We hypothesized that asymptomatic infection may represent a large proportion of SARS-CoV-2 infection in pediatric SOT recipients. METHODS: We queried Organ Transplant Tracking Record (OTTR) for all pediatric SOT recipients followed at our center and reviewed medical records to identify patients tested for SARS-CoV-2 between March 15, 2020 and June 30, 2021. Patients were tested by polymerase chain reaction (PCR): prior to planned procedures or because of symptoms; OR: tested by measurement of IgG to spike protein with their routine labs q 2-monthly. A positive PCR was called acute infection. A positive IgG with negative PCR was called convalescence. For immunologic studies, blood was obtained when the PCR or IgG was positive. Statistical comparisons were made between (1) acute infection versus convalescence; (2) acute infection versus SOT recipients without infection (called healthy controls); (3) liver transplant (LT) versus small bowel (SB)/multivisceral transplant (MVT); (4) positive versus negative test result. RESULTS: Of 257 LT recipients, 99 were tested: 6 were PCR positive, 13 were antibody positive. Of 150 SB/MVT recipients, 55 were tested: 4 were PCR positive, 6 were antibody positive. Of 8 simultaneous liver, kidney transplant recipients, 3 were tested: 1 was PCR positive. Symptoms when present were mostly mild. Patients with a positive test result were younger (6.3 vs 10.0 years; P = 0.017). We observed a rapid decline in viral load within 96 hours without a change in immunosuppression. Antibody lasted >8 months beyond the time it was monitored. Acute infection was associated with increased CD4 and CD8 T EM cell frequency ( P = 0.04, P = 0.03, respectively), decreased interferon (IFN)-γ production from T-cells (2.8% vs 11.3%; P = 0.006), and decreased CD8 TEMRA frequency (4.56% vs 11.70%; P = 0.006). CONCLUSIONS: Early in the pandemic, COVID-19 disease was mostly mild in pediatric SOT recipients with no rejection, patient death, or graft loss observed.

Mismatch epitope load predicts de novo-DSA-free survival in pediatric liver transplantation.

BACKGROUND: Our knowledge of de novo anti-HLA donor-specific antibodies (dnDSA) in liver transplantation continues to be defined. We hypothesized that differences of HLA-DR/DQ mismatches can improve precision in alloimmune risk categorization and be applied to tailor immunosuppression. METHODS: A retrospective chart review of 244 pediatric patients consecutively transplanted at our center between 2003 and 2019 was performed to identify patients tested for dnDSA. Records were queried for: demographics, pre-transplant diagnosis, biopsy-proven T-cell-mediated rejection (TCMR), radiology proven biliary complications, tacrolimus trough levels, dnDSA characteristics, and HLA typing. The eplet mismatch analyses were performed using HLAMatchmaker™ 3.1. All statistical analyses were conducted using R software version 3.40. RESULTS: There were 99 dnDSA-negative patients and 73 dnDSA-positive patients (n = 70 against class II and n = 3 against class I and II). ROC analysis identified optimal cutoff of eplet mismatch load for dnDSA and defined risk groups for an alloimmune outcome. Kaplan-Meier curves and log-rank tests showed high eplet mismatch load was associated with shorter dnDSA-free survival (log-rank p = .001). Multivariable Cox regression models showed that tacrolimus coefficient of variation and tacrolimus mean levels were significantly associated with dnDSA-free survival (p < .001 and p = .036). Fisher's exact test showed that dnDSA was associated with an increased likelihood of TCMR (OR 14.94; 95% CI 3.65 - 61.19; p < .001). Patients without TCMR were more likely to have dnDSA to HLA-DQ7 and less likely to have dnDSA to HLA-DQ2 (p = .03, p = .080). CONCLUSIONS: Mismatched epitope load predicts dnDSA-free survival in pediatric liver transplant, while dnDSA specificity may determine alloimmune outcome.

North American Biliary Stricture Management Strategies in Children After Liver Transplantation: A Multicenter Analysis From the Society of Pediatric Liver Transplantation (SPLIT) Registry.

Biliary strictures affect 4%-12% of pediatric liver transplantations. Biliary strictures can contribute to graft loss if left untreated; however, there remains no consensus on the best course of treatment. Study objectives included analyses of outcomes associated with biliary stricture management strategies via percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography (ERCP), or surgery. We identified pediatric liver transplantation recipients (2011-2016) with biliary strictures from the Society of Pediatric Liver Transplantation (SPLIT) registry and retrieved imaging, procedural, and operative reports from individual centers. Subanalyses were performed to specifically evaluate PTC and ERCP for "optimal biliary outcome" (OBO), defined as graft survival with stricture resolution and without recurrence or surgery. A total of 113 children with a median follow-up of 3.9 years had strictures diagnosed 100 days (interquartile range, 30-290) after liver transplantation; 81% were isolated anastomotic strictures. Stricture resolution was achieved in 92% within 101 days, more frequently with isolated anastomotic strictures (96%). 20% of strictures recurred, more commonly in association with hepatic artery thrombosis (32%). Patient and graft survival at 1 and 3 years were 99% and 98% and 94% and 92%, respectively. In a subgroup analysis of 79 patients with extrahepatic strictures managed by PTC/ERCP, 59% achieved OBO following a median of 4 PTC, and 75% following a median of 3 ERCP (P < 0.001). Among patients with OBO, those with ERCP had longer time intervals between successive procedures (41, 47, 54, 62, 71 days) than for PTC (27, 31, 36, 41, 48 days; P < 0.001). Allograft salvage was successful across all interventions. Stricture resolution was achieved in 92%, with 20% risk of recurrence. Resolution without recurrence was highest in patients with isolated anastomotic strictures and without hepatic artery thrombosis.

The effects of child anxiety and depression on concordance between parent-proxy and self-reported health-related quality of life for pediatric liver transplant patients.

BACKGROUND: HRQOL is a key outcome following pediatric LT. Parent-proxy reports may substitute for patients unable to report their own HRQOL. This study compared parent-proxy and self-reported HRQOL in children who have undergone LT. METHODS: Pediatric LT recipients between the ages of 8 and 18 years, and a parent, completed self and proxy versions of the PeLTQL questionnaire, PedsQL Generic and Transplant modules, and standardized measures of depression and anxiety. RESULTS: Data from 129 parent-patient dyads were included. Median parent age was 44 years, and most (89%) were mothers. Median patient age was 2.5 years at LT and 13.6 years at the time of study participation. Parents had significantly lower scores than patients on PedsQL total generic (70.8 ± 18.5 and 74.3 ± 19.0, p = .01), PeLTQL coping and adjustment (63.0 ± 15.6 and 67.3 ± 16.2, p < .01), and social-emotional (66.3 ± 14.9 and 71.9 ± 15.6, p < .001) domains. Higher patient anxiety and depression were related to larger absolute differences between parent-proxy and self-reported scores on all HRQOL measures (all p < .05). In this disparity, parents reported higher HRQOL scores than their child as self-reported anxiety and depression scores increased. CONCLUSIONS: Differences in concordance between parent-proxy and self-reported HRQOL scores can be more prominent when children have more symptoms of anxiety and depression. Children's mental health symptoms should be queried, if feasible, when interpreting differences in parent and child reports of HRQOL.

Graft Versus Host Disease After Intestinal Transplantation: A Single-center Experience.

BACKGROUND: Graft versus host disease (GVHD) is an uncommon but highly morbid complication of intestinal transplantation (ITx). In this study, we reviewed our 17-y experience with GVHD focusing on factors predicting GVHD occurrence and survival. METHODS: Retrospective review of 271 patients who received 1 or more ITx since program inception in 2003 with survival analysis using Cox proportional hazard modeling. RESULTS: Of 271 patients, 28 developed GHVD 34 (18-66) d after ITx presenting with rash or rash with fever in 26, rectosigmoid disease in 1, and hemolysis in 1; other sites, mainly rectosigmoid colon, were involved in 13. Initial skin biopsy demonstrated classic findings in 6, compatible findings in 14, and no abnormalities in 2. Additional sites of GVHD later emerged in 14. Of the 28 patients, 16 died largely from sepsis, the only independent hazard for death (hazard ratio [HR], 37.4181; P = 0.0008). Significant (P < 0.0500) independent hazards for occurrence of GVHD in adults were pre-ITx functional intestinal failure (IF) (HR, 15.2448) and non-IF diagnosis (HR, 20.9952) and early post-ITx sirolimus therapy (HR, 0.0956); independent hazards in children were non-IF diagnosis (HR, 4.3990), retransplantation (HR, 4.6401), donor:recipient age ratio (HR, 7.3190), and graft colon omission (HR, 0.1886). Variant transplant operation was not an independent GVHD hazard. CONCLUSIONS: Initial diagnosis of GVHD after ITx remains largely clinical, supported but not often confirmed by skin biopsy. Although GVHD risk is mainly recipient-driven, changes in donor selection and immunosuppression practice may reduce incidence and improve survival.

Anti-plasma cell treatment in refractory autoimmune hemolytic anemia in a child with multivisceral transplant.

BACKGROUND: Warm-antibody AIHA is known to complicate solid organ (SOT) and HSCT, the disease maybe refractory to standard therapy. Immunosuppressive therapies as well as IVIG, and rituximab have been the main stay of treatment. Over the past decade, B-lymphocyte targeted, anti-CD-20 antibody has been recognized in the treatment of autoimmune diseases and utilized in AIHA. Bortezomib, a proteasome inhibitor that causes apoptosis of plasma cells, is an appealing targeted therapy in secondary AIHA and has demonstrated efficacy in HSCT patients. From our experience, we advocate for early targeted therapy that combines B cell with plasma cell depletion. CASE REPORT: We describe a 4-year-old-girl with stage III neuroblastoma, complicated with intestinal necrosis needing multivisceral transplant developed warm AIHA 1-year after transplantation, and following an adenovirus infection. She received immunoglobulin therapy, rituximab, sirolimus, plasmapheresis, and long-term prednisolone with no sustained benefit while developing spinal fractures related to the latter therapy. She received bortezomib for intractable AIHA in combination with rituximab with no appreciable adverse effects. Three years later the child remains in remission with normal reticulocyte and recovered B cells. In the interim, she required chelation therapy for iron overload related to blood transfusion requirement during the treatment of AIHA. CONCLUSION: We propose early targeted anti-plasma cell therapy with steroid burst, IVIG, rituximab, and possible plasmapheresis may reduce morbidity in secondary refractory w-AIHA.

Impaired T-cell and antibody immunity after COVID-19 infection in chronically immunosuppressed transplant recipients.

Assessment of T-cell immunity to the COVID-19 coronavirus requires reliable assays and is of great interest, given the uncertain longevity of the antibody response. Some recent reports have used immunodominant spike (S) antigenic peptides and anti-CD28 co-stimulation in varying combinations to assess T-cell immunity to SARS-CoV-2. These assays may cause T-cell hyperstimulation and could overestimate antiviral immunity in chronically immunosuppressed transplant recipients, who are predisposed to infections and vaccination failures. Here, we evaluate CD154-expressing T-cells induced by unselected S antigenic peptides in 204 subjects-103 COVID-19 patients and 101 healthy unexposed subjects. Subjects included 72 transplanted and 130 non-transplanted subjects. S-reactive CD154+T-cells co-express and can thus substitute for IFNγ (n=3). Assay reproducibility in a variety of conditions was acceptable with coefficient of variation of 2-10.6%. S-reactive CD154+T-cell frequencies were a) higher in 42 healthy unexposed transplant recipients who were sampled pre-pandemic, compared with 59 healthy non-transplanted subjects (p=0.02), b) lower in Tr COVID-19 patients compared with healthy transplant patients (p<0.0001), c) lower in Tr patients with severe COVID-19 (p<0.0001), or COVID-19 requiring hospitalization (p<0.05), compared with healthy Tr recipients. S-reactive T-cells were not significantly different between the various COVID-19 disease categories in NT recipients. Among transplant recipients with COVID-19, cytomegalovirus co-infection occurred in 34%; further, CMV-specific T-cells (p<0.001) and incidence of anti-receptor-binding-domain IgG (p=0.011) were lower compared with non-transplanted COVID-19 patients. Healthy unexposed transplant recipients exhibit pre-existing T-cell immunity to SARS-CoV-2. COVID-19 infection leads to impaired T-cell and antibody responses to SARS-CoV-2 and increased risk of CMV co-infection in transplant recipients.

Efficacy and feasibility of ruxolitinib in chronic steroid-refractory GVHD in a pediatric intestine transplant.

Acute graft-versus-host disease (GvHD) has been a clinical problem in solid organ transplant that includes intestine due to the donor lymphoid tissue mass which accompanies the intestinal component of the graft. We report a case that demonstrated the efficacy and feasibility of ruxolitinib a JAK 1/2 inhibitor in the treatment of chronic steroid-refractory GVHD (SR-GVHD). The child developed SR-GVHD following a composite intestine transplant (small bowel, colon, liver, and pancreas). And after receiving ruxolitinib 1.25 mg (0.15 mg/kg/dose) per gastric tube (G-tube) daily, the child appeared to have improved skin rash and sigmoidoscopy was negative. Nonetheless, we encourage close monitoring of hematologic and infectious adverse effect during dose escalation, and individualizing patient maximum effective dose with the least adverse effect possible. We stress the importance of early diagnosis and hyper-alertness of GVHD in intestinal transplant patients.

Rejection of intestinal allotransplants is driven by memory T helper type 17 immunity and responds to infliximab.

Intestinal transplantation (ITx) can be life-saving for patients with advanced intestinal failure experiencing complications of parenteral nutrition. New surgical techniques and conventional immunosuppression have enabled some success, but outcomes post-ITx remain disappointing. Refractory cellular immune responses, immunosuppression-linked infections, and posttransplant malignancies have precluded widespread ITx application. To shed light on the dynamics of ITx allograft rejection and treatment resistance, peripheral blood samples and intestinal allograft biopsies from 51 ITx patients with severe rejection, alongside 37 stable controls, were analyzed using immunohistochemistry, polychromatic flow cytometry, and reverse transcription-PCR. Our findings inform both immunomonitoring and treatment. In terms of immunomonitoring, we found that while ITx rejection is associated with proinflammatory and activated effector memory T cells in the blood, evidence of treatment efficacy can only be found in the allograft itself, meaning that blood-based monitoring may be insufficient. In terms of treatment, we found that the prominence of intra-graft memory TNF-α and IL-17 double-positive T helper type 17 (Th17) cells is a leading feature of refractory rejection. Anti-TNF-α therapies appear to provide novel and safer treatment strategies for refractory ITx rejection; with responses in 14 of 14 patients. Clinical protocols targeting TNF-α, IL-17, and Th17 warrant further testing.

De novo hepatocellular carcinoma 18 years after liver and small bowel transplantation in a one-year-old pediatric patient.

De novo HCC following transplantation in a child is a rare occurrence. Even within the adult liver transplantation population, there are a limited number of published cases. In this report, we present a case of de novo HCC found in a child, post-multivisceral transplantation. A 19-year-old boy, at the age of one, received liver and small bowel transplantation due to short gut syndrome secondary to midgut volvulus and total parenteral nutrition-associated liver disease. Eighteen years later, he was found to have a large mass involving the right hepatic dome consistent with HCC. To the best of our knowledge, this is the second reported case after gut transplantation and the third case post-liver transplantation in the pediatric population.

CD69+ resident memory T cells are associated with graft-versus-host disease in intestinal transplantation.

Graft-versus-host disease (GvHD) is a common, morbid complication after intestinal transplantation (ITx) with poorly understood pathophysiology. Resident memory T cells (TRM ) are a recently described CD69+ memory T cell subset localizing to peripheral tissue. We observed that T effector memory cells (TEM ) in the blood increase during GvHD and hypothesized that they derive from donor graft CD69+TRM migrating into host blood and tissue. To probe this hypothesis, graft and blood lymphocytes from 10 ITx patients with overt GvHD and 34 without were longitudinally analyzed using flow cytometry. As hypothesized, CD4+ and CD8+CD69+TRM were significantly increased in blood and grafts of GvHD patients, alongside higher cytokine and activation marker expression. The majority of CD69+TRM were donor derived as determined by multiplex immunostaining. Notably, CD8/PD-1 was significantly elevated in blood prior to transplantation in patients who later had GvHD, and percentages of HLA-DR, CD57, PD-1, and naïve T cells differed significantly between GvHD patients who died vs. those who survived. Overall, we demonstrate that (1) there were significant increases in TEM at the time of GvHD, possibly of donor derivation; (2) donor TRM in the graft are a possible source; and (3) potential biomarkers for the development and prognosis of GvHD exist.

Factors Associated With 5- and 10-Year Survival After Intestinal Transplantation in Infants and Children.

OBJECTIVES: Intestinal transplantation is an option for permanent intestinal failure with parenteral nutrition intolerance. We sought to determine long-term intestinal graft survival in pediatric patients at our center and to identify factors influencing survival. METHODS: Retrospective chart review of 86 patients transplanted between 2003 and 2013, targeting potential explanatory variables related to demographics, perioperative factors, and postoperative complications. RESULTS: Intestinal graft survival was 71% and 65% after 5 and 10 years, respectively. Five-year graft survival was attained in 79% of patients with a history of anatomic intestinal failure compared with 45% with functional intestinal failure (P = 0.0055). Compared with nonsurvival, 5-year graft survival was also associated with reduced incidences of graft-versus-host disease (2% vs 16%, P = 0.0237), post-transplant lymphoproliferative disorder (3% vs 24%, P = 0.0067), and de novo donor-specific antibodies (19% vs 57%, P = 0.0451) plus a lower donor-recipient weight ratio (median 0.727 vs 0.923, P = 0.0316). Factors not associated with 5-year intestinal graft survival included graft rejection of any severity and inclusion of a liver graft. Factors associated with graft survival at 10 years were similar to those at 5 years. CONCLUSIONS: In our experience, outcomes in pediatric intestinal transplantation have improved substantially for anatomic but not functional intestinal failure. Graft survival depends on avoidance of severe infectious and immunological complications including GVHD, whereas inclusion of a liver graft provides no obvious survival benefit. Reduced success with functional intestinal failure may reflect inherently increased susceptibility to complications in this group.

Human norovirus targets enteroendocrine epithelial cells in the small intestine.

Human noroviruses are a major cause of diarrheal illness, but pathogenesis is poorly understood. Here, we investigate the cellular tropism of norovirus in specimens from four immunocompromised patients. Abundant norovirus antigen and RNA are detected throughout the small intestinal tract in jejunal and ileal tissue from one pediatric intestinal transplant recipient with severe gastroenteritis. Negative-sense viral RNA, a marker of active viral replication, is found predominantly in intestinal epithelial cells, with chromogranin A-positive enteroendocrine cells (EECs) identified as a permissive cell type in this patient. These findings are consistent with the detection of norovirus-positive EECs in the other three immunocompromised patients. Investigation of the signaling pathways induced in EECs that mediate communication between the gut and brain may clarify mechanisms of pathogenesis and lead to the development of in vitro model systems in which to evaluate norovirus vaccines and treatment.