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1.
Artigo em Inglês | MEDLINE | ID: mdl-38828781

RESUMO

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.

2.
Transplantation ; 108(2): 399-408, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37309025

RESUMO

Graft-versus-host disease (GvHD) remains a potentially fatal complication following intestinal transplant (ITx). Over the past decade, advances in the understanding of the pathophysiology of this complex immunological phenomenon have led to the reassessment of the host systemic immune response and have created a gateway for novel preventive and therapeutic strategies. Although sufficient evidence dictates the use of corticosteroids as a first-line option, the treatment for refractory disease remains contentious and lacks a standardized therapeutic approach. Timely diagnosis remains crucial, and the advent of chimerism detection and immunological biomarkers have transformed the identification, prognostication, and potential for survival after GvHD in ITx. The objectives of the following review aim to discuss the clinical and diagnostic features, pathophysiology, advances in immune biomarkers, as well as therapeutic opportunities in the prevention and treatment of GvHD in ITx.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/etiologia , Intestinos , Biomarcadores , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
3.
Transplantation ; 108(4): 827-835, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37723639

RESUMO

Intestinal transplant (ITx) rejection lacks a reliable noninvasive biomarker and rejection surveillance relies on serial endoscopies and mucosal biopsies followed by histologic assessment. Endoscopic biopsies are also essential for identifying other ITx-related complications such as infectious, allergic, and inflammatory graft enteritis as well as post-transplant lymphoproliferative disease or graft versus host disease. In spite of its central role in ITx, published guidelines on endoscopy and biopsy are lacking and significant variability between centers in terms of timing and technical performance exists. Therefore, an international expert group convened and discussed several aspects related to the surveillance endoscopy after ITx with the aim to summarize and standardize its practice. This article summarizes these considerations on endoscopic ITx monitoring and highlights practices of surveillance and for-cause endoscopy, biopsy techniques, pathologic evaluation, potential risks and complications, outsourcing, and less-invasive monitoring techniques.


Assuntos
Rejeição de Enxerto , Enteropatias , Humanos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/patologia , Intestinos/transplante , Transplante Homólogo , Endoscopia Gastrointestinal/efeitos adversos , Endoscopia Gastrointestinal/métodos , Aloenxertos , Enteropatias/patologia
4.
Transplant Direct ; 9(11): e1529, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37899780

RESUMO

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.

5.
Pediatr Transplant ; 26(4): e14251, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35279919

RESUMO

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.


Assuntos
Transplante de Rim , Transplante de Fígado , Criança , Epitopos , Rejeição de Enxerto , Sobrevivência de Enxerto , Antígenos HLA , Teste de Histocompatibilidade , Humanos , Isoanticorpos , Estudos Retrospectivos , Tacrolimo/uso terapêutico
6.
Transplant Direct ; 7(8): e731, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34291153

RESUMO

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.

7.
JPEN J Parenter Enteral Nutr ; 45(7): 1456-1465, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33305440

RESUMO

BACKGROUND: This analysis assessed combined safety data from 4 clinical studies of teduglutide in pediatric patients with short-bowel syndrome-associated intestinal failure (SBS-IF). METHODS: Safety data from teduglutide-treated patients in 4 clinical trials were pooled. The completed 12-week and 24-week phase 3 core studies (NCT01952080/EudraCT 2013-004588-30 and NCT02682381/EudraCT 2015-002252-27) enrolled children aged 1-17 years with SBS-IF. Patients could elect to enroll in ongoing open-label extensions (NCT02949362/EudraCT 2016-000863-17 and NCT02954458/EudraCT 2016-000849-30). Interim data from ongoing studies were included. RESULTS: Safety data are reported for 89 pediatric patients treated with teduglutide for a median (range) of 51.7 (5.0-94.7) weeks. Adverse events (AEs) were reported in all patients; the most common were vomiting (51.7%), pyrexia (43.8%), upper respiratory tract infection (41.6%), and cough (33.7%). Thirty-five patients (39.3%) had AEs considered related to teduglutide treatment; abdominal pain and vomiting were most frequent (5.6% each). Three serious AEs in 3 patients (3.4%) were considered related to teduglutide treatment: ileus, d-lactic acidosis, and gastrointestinal obstruction due to hard stools. All 3 events resolved. One cecal polyp was detected, which was not biopsied or found on repeat colonoscopy. No cases of neoplasia occurred. CONCLUSION: Based on integrated data from 4 clinical studies, including long-term follow-up for ≤161 weeks, teduglutide had a safety profile consistent with the individual core pediatric studies and as expected for pediatric patients with SBS-IF who never received teduglutide. The most frequent AEs reflected treatment with teduglutide, complications of the underlying disease, and typical childhood illnesses.


Assuntos
Nutrição Parenteral , Síndrome do Intestino Curto , Criança , Fármacos Gastrointestinais/efeitos adversos , Humanos , Peptídeos/efeitos adversos , Síndrome do Intestino Curto/complicações , Síndrome do Intestino Curto/tratamento farmacológico
8.
J Pediatr Gastroenterol Nutr ; 71(5): 617-623, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33093368

RESUMO

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.


Assuntos
Rejeição de Enxerto , Transplante de Fígado , Criança , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Lactente , Intestinos , Estudos Retrospectivos
9.
Nat Commun ; 11(1): 2759, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488028

RESUMO

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.


Assuntos
Células Enteroendócrinas/imunologia , Células Epiteliais/imunologia , Norovirus/fisiologia , Doença Aguda , District of Columbia , Células Enteroendócrinas/metabolismo , Gastroenterite/virologia , Genótipo , Humanos , Intestino Delgado/patologia , Intestino Delgado/virologia , Norovirus/genética , RNA Viral , Replicação Viral
10.
JPEN J Parenter Enteral Nutr ; 44(4): 621-631, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31495952

RESUMO

BACKGROUND: This study evaluated the safety and efficacy of teduglutide in pediatric patients with short bowel syndrome-associated intestinal failure (SBS-IF). METHODS: A 24-week, phase III trial with 2 randomized, double-blind teduglutide dose groups and a nonblinded standard of care (SOC) arm was used; patients received 0.025 mg/kg or 0.05 mg/kg teduglutide once daily. Safety end points included treatment-emergent adverse events (TEAEs) and growth parameters. The primary efficacy/pharmacodynamic end point was the number of patients who achieved a ≥20% reduction in parenteral support (PS) from baseline at week 24. RESULTS: All 59 enrolled patients completed the study (0.025 mg/kg, n = 24; 0.05 mg/kg, n = 26; SOC, n = 9). Baseline demographics and disease characteristics were comparable among groups. TEAEs were reported by 98% and 100% of patients in the teduglutide and SOC groups, respectively. The most common TEAEs in the teduglutide-treated groups were pyrexia and vomiting. The primary end point was achieved by 13 (54.2%), 18 (69.2%), and 1 (11.1%) patients who received 0.025 mg/kg teduglutide, 0.05 mg/kg teduglutide, and SOC, respectively (P < 0.05 vs SOC). Both 0.025-mg/kg and 0.05-mg/kg teduglutide groups showed clinically significant reductions in PS volume (P < 0.05 vs SOC), PS calories, days per week and hours per day of PS infusions, and increases in enteral nutrition and plasma citrulline at week 24 compared with baseline. Two (8.3%, 0.025 mg/kg teduglutide) and 3 patients (11.5%, 0.05 mg/kg teduglutide) achieved enteral autonomy. CONCLUSION: The safety profile of teduglutide was similar to that reported previously in children and adults. Treatment with teduglutide was associated with significant reductions in PS for pediatric patients with SBS-IF over 24 weeks.


Assuntos
Fármacos Gastrointestinais/uso terapêutico , Peptídeos/uso terapêutico , Síndrome do Intestino Curto , Adulto , Idoso , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Masculino , Nutrição Parenteral , Síndrome do Intestino Curto/complicações , Síndrome do Intestino Curto/tratamento farmacológico
11.
Transplantation ; 104(5): 937-946, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31815899

RESUMO

In 2001, a Statement was published that described indications for intestinal transplantation in patients with intestinal failure expected to require parenteral nutrition indefinitely. Since 2001, advances in the management of intestinal failure including transplantation and patient survival, both on extended parenteral nutrition and after transplantation, have improved, leading to a reduction in the number of intestinal transplants worldwide from a peak of 270 per year in 2008 to 149 per year in 2017. These changes suggest that the original 2001 Statement requires reassessment. All patients with permanent intestinal failure should be managed by dedicated multidisciplinary intestinal rehabilitation teams. Under care of these teams, patients should be considered for intestinal transplantation in the event of progressive intestinal failure-associated liver disease, progressive loss of central vein access, and repeated life-threatening central venous catheter-associated infections requiring critical care. Additional indications for transplantation include large desmoid tumors and other intra-abdominal tumors with reasonable expectation of posttransplant cure, extensive mesenteric vein thrombosis and intestinal infarction, total intestinal aganglionosis, and nonrecoverable congenital secretory diarrhea. Quality of life typically improves after successful intestinal transplantation and may support the decision to proceed with transplantation when other indications are present. However, the requirement for life-long immunosuppression and its associated side effects preclude intestinal transplantation if motivated only by an expectation of improved quality of life. Increasing experience with intestinal transplantation and critical appraisal of transplant outcomes including graft survival and patient quality of life together with potential advances in immunosuppression can be expected to influence transplant practices in the future.


Assuntos
Consenso , Terapia de Imunossupressão/métodos , Enteropatias/terapia , Intestinos/transplante , Nutrição Parenteral Total/métodos , Sobrevivência de Enxerto , Humanos , Qualidade de Vida
12.
Transplantation ; 103(10): 2144-2149, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30720689

RESUMO

BACKGROUND: An 11-year-old girl with dedicator of cytokinesis 8 (DOCK8) deficiency was proposed for potentially curative hematopoietic stem cell transplantation (HSCT), the donor being her haploidentical mother. However, end-stage liver disease caused by chronic Cryptosporidium infection required liver transplantation before HSCT. METHODS: Consequently, a staged approach of a sequential liver transplant followed by a HSCT was planned with her mother as the donor for both liver and HSCT. RESULTS: The patient successfully underwent a left-lobe orthotopic liver transplant; however, she developed a biliary leak delaying the HSCT. Notably, the recipient demonstrated 3% donor lymphocyte chimerism in her peripheral blood immediately before HSCT. Haploidentical-related donor HSCT performed 2 months after liver transplantation was complicated by the development of acyclovir-resistant herpes simplex virus viremia, primary graft failure, and sinusoidal obstruction syndrome. The patient died from sinusoidal obstruction syndrome-associated multiorgan failure with Candida sepsis on day +40 following HSCT. CONCLUSIONS: We discuss the many considerations inherent to planning for HSCT preceded by liver transplant in patients with primary immunodeficiencies, including the role of prolonged immunosuppression and the risk of infection before immune reconstitution. We also discuss the implications of potential recipient sensitization against donor stem cells precipitated by exposure of the recipient to the donor lymphocytes from the transplanted organ.


Assuntos
Criptosporidiose/cirurgia , Fatores de Troca do Nucleotídeo Guanina/deficiência , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante de Fígado/métodos , Imunodeficiência Combinada Severa/cirurgia , Adulto , Inibidores de Calcineurina/administração & dosagem , Criança , Criptosporidiose/imunologia , Criptosporidiose/microbiologia , Cryptosporidium/imunologia , Cryptosporidium/isolamento & purificação , Feminino , Humanos , Doadores Vivos , Mães , Agonistas Mieloablativos/administração & dosagem , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/imunologia , Condicionamento Pré-Transplante/métodos , Transplante Haploidêntico/métodos , Resultado do Tratamento
13.
Cleft Palate Craniofac J ; 50(6): 747-50, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22937760

RESUMO

Background : Acetaminophen is a widely used analgesic and antipyretic agent in the pediatric population. While the hepatotoxic effects of the drug have been well recognized in cases of acute overdose and chronic supratherapeutic doses, the toxic effects of acetaminophen are rarely documented in cases where therapeutic guidelines are followed. Case : An 8-month-old boy underwent cleft palate repair and placement of bilateral myringotomy tubes. His anesthetic course was uneventful, consisting of maintenance with desflurane and fentanyl. He received acetaminophen for routine postoperative pain management and was tolerating liquids and discharged home on postoperative day 1. On day 3, the child was profoundly lethargic with multiple episodes of emesis and was taken to the emergency department. He suffered a 45-second tonic-clonic seizure in transport to the regional children's medical center, and initial laboratory results demonstrated acute hepatitis with AST 24,424 U/L, ALT 12,885 U/L, total bilirubin 3.1 mg/dL, and a serum acetaminophen level of 83 µg/mL. Aggressive supportive measures including blood products and periprocedural fresh frozen plasma, piperacillin/tazobactam, and intravenous infusions of N-acetylcysteine, sodium phenylacetate and sodium benzoate, carnitine, and citrulline were administered. His metabolic acidosis and acute hepatitis began to correct by day 4, and he was discharged home without further surgical intervention on day 15. Conclusion : Although acetaminophen is an effective and commonly used analgesic in pediatric practice, hepatotoxicity is a potentially devastating complication. This report challenges the appropriateness of existing guidelines for acetaminophen administration and emphasizes the importance of close follow-up and hydration after even relatively minor surgery.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Acetilcisteína , Fissura Palatina , Humanos , Infusões Intravenosas , Falência Hepática Aguda
15.
J Clin Oncol ; 23(27): 6481-8, 2005 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-16170157

RESUMO

PURPOSE: To evaluate the efficacy of a low-dose chemotherapy regimen in children with Epstein-Barr virus (EBV) -positive, post-transplantation lymphoproliferative disease (PTLD) after organ transplantation who have experienced failure with front-line therapy for PTLD. PATIENTS AND METHODS: Eligible patients received cyclophosphamide (600 mg/m2 intravenous for 1 day) and prednisone (2 mg/kg orally for 5 days) every 3 weeks for six cycles. RESULTS: Thirty-six patients treated on study were assessable for analyses. Front-line therapies for PTLD before study entry included immune suppression reduction or withdrawal (n = 36), antiviral therapy (n = 33), surgical resection (n = 8), rituximab (n = 2), and interferon alfa (n = 1). Reasons for failure of front-line therapy included progressive disease (PD; n = 33) and persistent disease with concurrent allograft rejection (n = 3). Thirty patients (83%) had stage III to IV disease, 92% had extranodal disease, and 75% had > or = three sites of disease. The overall response rate was 83% (75% complete response + 8% partial response). The relapse rate was 19%, with only one of five relapsed patients alive and disease-free. Four patients presented with fulminant, disseminated PTLD; only one of these four patients achieved a response, and all four died of PD. Two patients died of treatment-related toxicity. Three patients (8%) experienced allograft loss, but two of the three patients are alive and disease-free after a second transplantation. The 2-year overall, relapse-free, and failure-free (without PTLD and with functioning original allograft) survival rates were 73%, 69%, and 67%, respectively. CONCLUSION: This low-dose chemotherapy regimen is effective for children with EBV-positive, nonfulminant PTLD who have experienced treatment failure with front-line therapy, and this study represents the largest series of PTLD patients treated prospectively with a uniform chemotherapy regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/virologia , Transplante de Órgãos/efeitos adversos , Adolescente , Criança , Pré-Escolar , Intervalos de Confiança , Ciclofosfamida/uso terapêutico , Relação Dose-Resposta a Droga , Infecções por Vírus Epstein-Barr/diagnóstico , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Transtornos Linfoproliferativos/diagnóstico , Masculino , Metotrexato/uso terapêutico , Transplante de Órgãos/métodos , Prednisona/uso terapêutico , Probabilidade , Estudos Prospectivos , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento
16.
J Pediatr Gastroenterol Nutr ; 40(3): 328-33, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15735487

RESUMO

OBJECTIVES: The human caliciviruses, which include Norwalk-like viruses (or Noroviruses) and Sapporo viruses, commonly cause epidemic and endemic viral gastroenteritis of short duration in healthy individuals. However, the impact of human calicivirus in immunosuppressed populations has not been established. The authors report five pediatric patients who developed human calicivirus enteritis after intestinal transplantation. METHODS: Infection was documented with repetitive reverse transcription polymerase chain reaction testing with nucleotide sequencing of tissue and lumen fluid specimens. RESULTS: A single strain, type Miami Beach, affected all patients in the hospital with an apparent index case. A potential mode of transmission was not defined. Severe osmotic or secretory diarrhea necessitated intravenous fluid therapy for 40 days or more in three of the five infants. Concurrent or recent subclinical allograft infection with adenovirus in two patients was associated with more severe symptoms. Virus excretion exceeded 80 days in two patients. Differentiation of human calicivirus enteritis from allograft rejection was difficult, as both disorders were associated with increased enterocyte apoptosis and inflammation. Intensification of immunosuppressive therapy because of suspected rejection appeared to prolong symptoms. CONCLUSION: These findings demonstrate that human calicivirus can be a significant pathogen in intestinal transplant recipients and potentially in other immunocompromised patients.


Assuntos
Infecções por Caliciviridae/etiologia , Caliciviridae/isolamento & purificação , Enterite/etiologia , Terapia de Imunossupressão/efeitos adversos , Intestinos/transplante , Fatores Etários , Infecções por Caliciviridae/patologia , Criança , Pré-Escolar , Infecção Hospitalar , Enterite/patologia , Rejeição de Enxerto , Humanos , Lactente , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Hum Pathol ; 35(10): 1236-40, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15492991

RESUMO

Human calicivirus (HuCV), a common cause of mild gastroenteritis in the general population, produces a prolonged diarrheal illness in pediatric recipients of small intestinal transplant (IT). By use of reverse-transcription polymerase chain reaction to detect the viral RNA polymerase gene in stool and tissue from gastrointestinal biopsies, 5 pediatric IT recipients with high-volume diarrhea were diagnosed with HuCV enteritis. Histopathologic findings of biopsies obtained at different gastrointestinal sites were studied retrospectively to identify characteristic features of HuCV enteritis and to distinguish these changes from rejection. Controls were 8 pediatric IT recipients with high-volume diarrhea but negative HuCV reverse-transcription polymerase chain reaction assays during the same time period. All HuCV biopsies showed increased mononuclear infiltrates in the lamina propria and villous blunting. Reactive disarray of surface epithelial cells and increased apoptosis in the surface epithelium and superficial lamina propria were characteristic features (in 4/5 patients). Increased glandular apoptosis was also present in 3/5 patients. Findings were more pronounced in jejunal allograft than ileal allograft, and were present in both graft and native bowel. In comparison with the control group, the architectural changes, surface epithelial reactive changes, and superficial apoptosis were characteristic of HuCV enteritis, while the presence of glandular apoptosis was a feature shared with cases of mild acute cellular rejection HuCV may cause severe allograft dysfunction after pediatric IT. Calicivirus infection has clinical and histological features that overlap with allograft rejection. Knowledge of the characteristic histologic features of HuCV enteritis aids in differential diagnosis.


Assuntos
Infecções por Caliciviridae/diagnóstico , Enterite/virologia , Intestino Delgado/transplante , Apoptose , Biópsia , Infecções por Caliciviridae/patologia , Pré-Escolar , RNA Polimerases Dirigidas por DNA/genética , Diagnóstico Diferencial , Diarreia/virologia , Fezes/virologia , Rejeição de Enxerto/diagnóstico , Humanos , Lactente , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Am J Transplant ; 4(3): 414-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14961995

RESUMO

Biopsy is the only means to identify intestinal graft rejection. Plasma citrulline (P-Cit) has been proposed as a marker for rejection after intestinal transplant (IT), but normative data is lacking. We analyzed P-Cit in IT recipients without rejection or other histological abnormalities. In 40 patients, P-Cit was measured with a Beckman amino acid analyzer within 24 h of protocol or clinically indicated endoscopic biopsy procured > 6 and < 360 days post-IT. Measurements included for analysis corresponded to normal (or minimally abnormal) biopsies that remained so for 7 days. These criteria were met by 145 samples from 10 adults and 14 children. Overall mean P-Cit (nmol/mL) was 34.0 +/- 19.9. Mean P-Cit was 22.2 +/- 13.2 between 6 and 30 days post-IT, 34.9 +/- 17.2 (p = 0.001) between 30 and 60 days, 43.6 +/- 15.8 between 60 and 90 days (p = 0.001), then stable until the end of the first year. Plasma citrulline was lower in 13 patients with body surface area (BSA) < or = 1 m2 vs. 11 patients with BSA > or = 1.1 m2 (p = 0.0001). Plasma citrulline increased linearly during the first 120 days in both BSA groups (r = 0.573 and r = 0.512; p = 0.0001). Within 3 months after IT, variations in P-Cit based on body size and postop interval should be considered when evaluating the need for histological confirmation of graft dysfunction.


Assuntos
Citrulina/sangue , Intestino Delgado/transplante , Biópsia , Superfície Corporal , Citrulina/metabolismo , Humanos , Fatores de Tempo
19.
Transplantation ; 76(1): 183-9, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12865807

RESUMO

BACKGROUND: The purpose of this study was to determine the prevalence of adenoviral infection in pediatric small bowel transplantation (SBT) recipients, examine risk factors for progression to histologic disease, and examine the impact of adenovirus on outcome. METHODS: Beginning in July 2000, all SBT recipients had viral cultures for adenovirus, cytomegalovirus (CMV), and herpes simplex virus (HSV) obtained routinely during graft biopsies. The medical records were retrospectively reviewed for frequency and site of viral culture, types and doses of immunosuppressive drugs, episodes of rejection, histology of allograft biopsies, and other infections. Adenoviral isolates were typed by polymerase chain reaction and type-specific neutralization assays. RESULTS: All 14 SBT recipients who met enrollment criteria had evidence of adenoviral infection (intestinal graft, 13; liver graft, 1). Eight of 14 developed histologic disease with identifiable adenoviral intranuclear inclusions. In contrast, CMV enteritis was identified in only one patient, who subsequently also developed adenoviral disease. No other viruses were detected. Adenoviral cultures were first positive within 30 days of transplant in nine. Patients with histologic disease were more likely than those without to have received intensive corticosteroid therapy (P<0.007), had virus isolated from more than one site (P=0.03), and had persistent positive cultures (P<0.01). CONCLUSIONS: Adenovirus was commonly isolated from children undergoing intestinal transplantation. Progression to disease may be associated with more intensive immunosuppressive therapy and inability to clear virus.


Assuntos
Infecções por Adenoviridae/epidemiologia , Mucosa Intestinal/patologia , Intestino Delgado/transplante , Complicações Pós-Operatórias/virologia , Biópsia , Criança , Pré-Escolar , Enterite/epidemiologia , Enterite/virologia , Feminino , Hepatite Viral Humana/patologia , Humanos , Lactente , Infecções/classificação , Infecções/epidemiologia , Mucosa Intestinal/transplante , Intestino Delgado/patologia , Intestino Delgado/virologia , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Transplante Homólogo/patologia
20.
Ann Surg ; 235(3): 435-9, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11882766

RESUMO

OBJECTIVE: To evaluate experience with isolated orthotopic liver transplantation in children with liver failure associated with short bowel syndrome (SBS). SUMMARY BACKGROUND DATA: Infants who have liver failure as a result of SBS are frequently referred for consideration for combined liver and small bowel transplantation. In a few patients the liver disease develops despite a seemingly adequate bowel, which if given time and appropriate management has the potential for full enteral adaptation. There is a limited literature suggesting the utility of OLT without replacement of the native bowel. The advantages over combined liver and small bowel transplantation are clear: organ availability is greater, liver-reduction techniques are well established, lower immunosuppression is required, and there is greater experience in the care of children after orthotopic liver transplantation. METHODS: Eleven infants, considered to have a good prospect of eventual gut adaptation to full enteral nutrition if it were not for their advanced liver disease, underwent isolated orthotopic liver transplantation. Age range was 6.5 to 17.7 months. All patients had been dependent on parenteral feeding but had also shown significant enteral tolerance at some time before listing for transplantation. Advanced liver disease was apparent both clinically and on histologic examination. All were jaundiced and had low albumin levels, and most had coagulopathy. As a group the infants had growth retardation. Estimated remaining length of small bowel beyond the ligament of Treitz was in the range of 25 to more than 100 cm. Six infants retained their ileocecal valve. RESULTS: Thirteen liver transplants were performed in the 11 patients. A combination of whole livers (n = 6) and reduced-size grafts, of which three were from living-related donors, were used. Biliary anastomosis was duct-to-duct in eight instances and involved a short Roux limb in the others. Eight patients are alive with follow-up of 15 to 66 months. Three deaths have occurred after transplantation as a result of sepsis. Of eight surviving patients, only two continue to receive intravenous support and in both there is increasing enteral tolerance. Since transplantation, all surviving children have shown adequate growth with maintenance of pretransplant centiles. CONCLUSIONS: In selected infants with liver failure secondary to short bowel syndrome in whom complete enteral autonomy is anticipated, isolated liver transplantation can offer long-term survival.


Assuntos
Falência Hepática/etiologia , Falência Hepática/cirurgia , Transplante de Fígado , Síndrome do Intestino Curto/complicações , Humanos , Lactente , Resultado do Tratamento
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