Neurological complications of solid organ transplantation / Complicações neurológicas no transplante de órgãos sólidos

ABSTRACT Solid organ transplantation is a significant development in the treatment of chronic kidney, liver, heart and lung diseases. This therapeutic approach has increased patient survival and improved quality of life. New surgical techniques and immunosuppressive drugs have been developed to achieve better outcomes. However, the variety of neurological complications following solid organ transplantation is broad and carries prognostic significance. Patients may have involvement of the central or peripheral nervous system due to multiple causes that can vary depending on time of onset after the surgical procedure, the transplanted organ, and the intensity and type of immunosuppressive therapy. Neurological manifestations following solid organ transplantation pose a diagnostic challenge to medical specialists despite extensive investigation. This review aimed to provide a practical approach to help neurologists and clinicians assess and manage solid organ transplant patients presenting with acute or chronic neurological manifestations.

RESUMO O transplante de órgãos sólidos é um importante avanço no tratamento de doenças crônicas renal, hepática e cardíaca. Esta terapia tem aumentado a sobrevida e melhorado a qualidade de vida dos pacientes. Novas técnicas cirúrgicas e imunossupressores tem sido desenvolvidos para alcançar melhores desfechos. Entretanto, a variedade de complicações neurológicas que acompanham o transplante de órgãos sólidos é ampla, e carrega significado prognóstico. Pacientes podem ter acometimento do sistema nervoso central ou periférico devido a múltiplas causas que podem variar conforme o tempo após a realização da cirurgia, órgão transplantado e grau e tipo de terapia de imunossupressão. Manifestações neurológicas após o transplante de órgãos sólidos representam um desafio diagnóstico para médicos especialistas apesar de extensa investigação. O objetivo desta revisão é oferecer uma abordagem prática para ajudar neurologistas e clínicos a avaliar e manejar pacientes com transplante de órgãos sólidos que se apresentem com manifestações neurológicas agudas ou crônicas.

Desafíos terapéuticos en la enfermedad injerto contra huésped / Therapeutic challenges in graft versus host disease

La enfermedad injerto contra huésped es una entidad en la cual las células inmunológicas competentes de un tejido injertado reconocen y dañan antígenos presentes en el receptor del trasplante, que es incapaz de defenderse de ellas. Es una complicación frecuente del trasplante alogénico de médula ósea, y con menor frecuencia se produce luego de trasplantes de órganos sólidos o transfusiones de hemoderivados no irradiados. Se comunica el caso de una paciente de sexo femenino de 23 años, con leucemia linfoblástica aguda.y trasplante alogénico de médula ósea, que presentó una enfermedad injerto contra huésped con compromiso cutáneo y gastrointestinal dependiente de corticoides, con mejoría de los signos y síntomas cutáneos luego del tratamiento con infliximab y fotoféresis extracorpórea. (AU)

Graft versus host disease is an entity in which competent grafted immune cells recognize and damage tissue antigens present in the transplant recipient, who is unable to defend from them. It is one of the most serious complications in patients undergoing allogeneic bone marrow transplantation, although less frequently it may be associated with solid organ transplants or transfusions of not irradiated blood products. We report the case of a 23 year-old patient with acute lymphoblastic leukemia and allogeneic bone marrow transplantation, that presented graft versus host disease with skin and gastrointestinal involvement, dependent on corticosteroids, that showed improvement in signs and skin symptoms after treatment with infliximab and extracorporeal photopheresis. (AU)

Características clínico-epidemiológicas de la estrongiloidiasis en pacientes portadores de co-morbilidades / Clinical and epidemiological characteristics of strongyloidiasis in patients with comorbidities

The strongyloidiasis is a parasitic disease that poses as a serious public health problem, mainly in tropical and subtropical countries. Over the years, some conditions, such as advances in corticosteroid treatment and immunosuppressive diseases, have improved not only the increase in cases of strongyloidiasis, but also the emergence of severe forms of the disease and / or deaths. For these reasons, the objective of this study is to make a critical analysis of the occurrence of strongyloidiasis in patients with comorbidities, describing clinical and epidemiological characteristics associated with these diseases that can highlight the importance of monitoring this parasitosis in most susceptible groups.

La estrongiloidiasis es una parasitosis que representa un grave problema de salud pública, principalmente en países ubicados en regiones tropicales y subtropicales. A lo largo de los años, algunas condiciones, como por ejemplo, avances en el tratamiento con corticosteroides y enfermedades que evolucionan con inmunosupresión, han favorecido no solamente al aumento de casos de estrongiloidiasis, sino también al surgimiento de formas graves de la enfermedad y/u decesos. Por lo expuesto, el objetivo del presente estudio fue realizar un análisis crítico de la ocurrencia de la estrongiloidiasis en portadores de co-morbilidades, describiendo las características clínico-epidemiológicas de esa asociación que puedan resaltar la importancia de vigilar esta parasitosis en grupos considerados más susceptibles.

Hydrogen, a potential safeguard for graft-versus-host disease and graft ischemia-reperfusion injury?

Post-transplant complications such as graft-versus-host disease and graft ischemia-reperfusion injury are crucial challenges in transplantation. Hydrogen can act as a potential antioxidant, playing a preventive role against post-transplant complications in animal models of multiple organ transplantation. Herein, the authors review the current literature regarding the effects of hydrogen on graft ischemia-reperfusion injury and graft-versus-host disease. Existing data on the effects of hydrogen on ischemia-reperfusion injury related to organ transplantation are specifically reviewed and coupled with further suggestions for future work. The reviewed studies showed that hydrogen (inhaled or dissolved in saline) improved the outcomes of organ transplantation by decreasing oxidative stress and inflammation at both the transplanted organ and the systemic levels. In conclusion, a substantial body of experimental evidence suggests that hydrogen can significantly alleviate transplantation-related ischemia-reperfusion injury and have a therapeutic effect on graft-versus-host disease, mainly via inhibition of inflammatory cytokine secretion and reduction of oxidative stress through several underlying mechanisms. Further animal experiments and preliminary human clinical trials will lay the foundation for hydrogen use as a drug in the clinic.

Tamizaje de infecciones por virus Epstein Barr en muestras de sangre mediante el uso de una PCR en tiempo real previo a la cuantificación de la carga viral / Screening for Epstein Barr virus infections in blood samples using real-time PCR previous to viral load quantification

El desorden linfoproliferativo postrasplante es una de las complicaciones más importantes producidas por el virus Epstein Barr (EBV) en pacientes trasplantados de órganos sólidos y de médula ósea ya que afecta la sobrevida del paciente y del injerto. En estos pacientes se han reportado altos niveles de carga viral en sangre periférica que preceden al desarrollo del desorden linfoproliferativo postrasplante. Por esto el monitoreo de la carga viral (CV) permite detectar pacientes en riesgo a desarrollar esta patología para iniciar una terapia preventiva. El objetivo de este trabajo fue desarrollar una técnica de PCR en tiempo real cualitativa (RT PCR) que permitiera ser utilizada como prueba de tamizaje previo a la determinación de CV EBV. De esta manera se podrían minimizar el costo que implicaría la utilización de un método cuantitativo comercial para todas las muestras que ingresaran al monitoreo viral. Teniendo en cuenta el desempeño de la RT PCR desarrollada, se estableció Ct ≤ 37 como valor límite para evitar amplificación inespecífica y seleccionar las muestras candidatas a la determinación de CV EBV. Dicho punto de corte presentó una sensibilidad diagnóstica relativa de 80%, una especificidad diagnóstica relativa de 85%, un valor predictivo positivo (VPP) de 53% y un valor predictivo negativo (VPN) de 95%. Para ello se consideró que valores de CV EBV< 4000 copias/ml sangre eran bajas o no presentaban riesgo de desarrollar complicaciones. El límite de detección LoD 95% fue de 280 copias de EBV/ml sangre (66 ­ 1184, IC 95%). Esta técnica demostró tener una buena performance analítica, ser de fácil implementación y el punto de corte seleccionado nos permitió realizar un buen tamizaje de muestras de pacientes trasplantados que resultaban ser candidatas a la determinación de CV, con la consiguiente disminución de costos (AU)

Post-transplant lymphoproliferative disorder is one of the main complications caused by the Epstein Barr virus (EBV) in solidorgan and bone-marrow transplantation patients affecting survival of both the patient and the graft. High levels of viral load (VL) in peripheral blood preceding the development of posttransplant lymphoproliferative disorder have been reported in these patients. Therefore, VL monitoring allows detection of patients who are at risk of developing this disease to start preventive treatment. The aim of this study was to develop a qualitative real-time PCR technique to use as an early screening test to determine EBV VL. This test may minimize costs related to the use of a commercial quantitative method for all the samples that enter for viral screening. Considering the performance of the RT PCR method developed, a Ct ≤ 37 was established as the cut-off limit to avoid unspecific amplification and select the samples that are candidates for EBV VL determination. This cut-off point had a relative diagnostic sensitivity of 80%, a relative diagnostic specificity of 85%, a positive predictive value (PPV) of 53% and a negative predictive value (NPV) of 95%. Thus, an EBV VL< 4000 copies/ml blood was considered to be low and not to be a risk for developing complications. The 95% limit of detection was 280 copies of EBV/ml blood (66­1184, 95%CI). The technique showed to be of good analytical performance and easy implementation. The cut-off point allowed a good screening of the samples of transplanted patients to detect those who are candidates for VL determination at a lower cost (AU)

Epstein Barr virus-associated lymphoproliferative diseases: the virus as a therapeutic target

Epstein Barr virus (EBV)-associated lymphoproliferative diseases (LPDs) express all EBV latent antigens (type III latency) in immunodeficient patients and limited antigens (type I and II latencies) in immunocompetent patients. Post-transplantation lymphoproliferative disease (PTLD) is the prototype exhibiting type III EBV latency. Although EBV antigens are highly immunogenic, PTLD cell proliferation remains unchecked because of the underlying immunosuppression. The restoration of anti-EBV immunity by EBV-specific T cells of either autologous or allogeneic origin has been shown to be safe and effective in PTLDs. Cellular therapy can be improved by establishing a bank of human leukocyte antigen-characterized allogeneic EBV-specific T cells. In EBV+ LPDs exhibiting type I and II latencies, the use of EBV-specific T cells is more limited, although the safety and efficacy of this therapy have also been demonstrated. The therapeutic role of EBV-specific T cells in EBV+ LPDs needs to be critically reappraised with the advent of monoclonal antibodies and other targeted therapy. Another strategy involves the use of epigenetic approaches to induce EBV to undergo lytic proliferation when expression of the viral thymidine kinase renders host tumor cells susceptible to the cytotoxic effects of ganciclovir. Finally, the prophylactic use of antiviral drugs to prevent EBV reactivation may decrease the occurrence of EBV+ LPDs.

Role of dipeptidyl peptidase-4 inhibitors in new-onset diabetes after transplantation

Despite strict pre- and post-transplantation screening, the incidence of new-onset diabetes after transplantation (NODAT) remains as high as 60%. This complication affects the risk of cardiovascular events and patient and graft survival rates. Thus, reducing the impact of NODAT could improve overall transplant success. The pathogenesis of NODAT is multifactorial, and both modifiable and nonmodifiable risk factors have been implicated. Monitoring and controlling the blood glucose profile, implementing multidisciplinary care, performing lifestyle modifications, using a modified immunosuppressive regimen, administering anti-metabolite agents, and taking a conventional antidiabetic approach may diminish the incidence of NODAT. In addition to these preventive strategies, inhibition of dipeptidyl peptidase-4 (DPP4) by the gliptin family of drugs has recently gained considerable interest as therapy for type 2 diabetes mellitus and NODAT. This review focuses on the role of DPP4 inhibitors and discusses recent literature regarding management of NODAT.

Management of post-transplant Epstein-Barr virus-related lymphoproliferative disease in solid organ and hematopoietic stem cell recipients

Epstein-Barr virus (EBV)-related post-transplant lymphoproliferative disease (PTLD) is one of the most serious complications associated with solid organ and hematopoietic stem cell transplantation. PTLD is most frequently seen with primary EBV infection post-transplant, a common scenario for pediatric solid organ recipients. Risk factors for infection or reactivation of EBV following solid organ transplant are stronger immunosuppressive therapy regimens, and being seronegative for receptor. For hematopoietic stem cell transplantation, the risk factors relate to the type of transplant, human leukocyte antigen disparity, the use of stronger immunosuppressants, T-cell depletion, and severe graft-versus-host disease. Mortality is high, and most frequent in patients who develop PTLD in the first six months post-transplant. The primary goal of this article is to provide an overview of the clinical manifestations, diagnosis, accepted therapies, and management of EBV infection in transplant recipients, and to suggest that the adoption of monitoring protocols could contribute to a reduction in related complications.

Growth following solid organ transplantation in childhood

One of the ultimate goals of successful solid organ transplantation in pediatric recipients is attaining an optimal final adult height. This manuscript will discuss growth following transplantation in pediatric recipients of kidney, liver, heart, lung or small bowel transplants. Remarkably similar factors impact growth in all of these recipients. Age is a primary factor, with younger recipients exhibiting the greatest immediate catch-up growth. Graft function is a significant contributing factor, with a reduced glomerular filtration rate correlating with poor growth in kidney recipients and the need for re-transplantation with impaired growth in liver recipients. The known adverse impact of steroids on growth has led to modification of the steroid dose and even steroid withdrawal and avoidance. In kidney and liver recipients, this strategy has been associated with the development of acute rejection. In infant heart transplantation, avoiding maintenance corticosteroid immunosuppression is associated with normal growth velocity in the majority of patients. With marked improvements in patient and graft survival rates in pediatric organ recipients, quality of life issues, such as normal adult height, should now receive paramount attention. In general, normal growth following solid organ transplantation should be an achievable goal that results in normal adult height.

Long-term outcomes of children after solid organ transplantation

Solid organ transplantation has transformed the lives of many children and adults by providing treatment for patients with organ failure who would have otherwise succumbed to their disease. The first successful transplant in 1954 was a kidney transplant between identical twins, which circumvented the problem of rejection from MHC incompatibility. Further progress in solid organ transplantation was enabled by the discovery of immunosuppressive agents such as corticosteroids and azathioprine in the 1950s and ciclosporin in 1970. Today, solid organ transplantation is a conventional treatment with improved patient and allograft survival rates. However, the challenge that lies ahead is to extend allograft survival time while simultaneously reducing the side effects of immunosuppression. This is particularly important for children who have irreversible organ failure and may require multiple transplants. Pediatric transplant teams also need to improve patient quality of life at a time of physical, emotional and psychosocial development. This review will elaborate on the long-term outcomes of children after kidney, liver, heart, lung and intestinal transplantation. As mortality rates after transplantation have declined, there has emerged an increased focus on reducing longer-term morbidity with improved outcomes in optimizing cardiovascular risk, renal impairment, growth and quality of life. Data were obtained from a review of the literature and particularly from national registries and databases such as the North American Pediatric Renal Trials and Collaborative Studies for the kidney, SPLIT for liver, International Society for Heart and Lung Transplantation and UNOS for intestinal transplantation.

Induction of Donor-Specific Tolerance: Is This Achievable?

No abstract available.

Prevenção referente às modalidades alternativas de transmissão do trypanosoma cruzi no Brasil / Prevention concerning the different alternative routes for transmission of Trypanosoma cruzi in Brazil

Consideram-se habituais em doença de Chagas humana os mecanismos vetorial, transfusional e congênito de transmissão. Acidental, oral e por transplantes são ditos alternativos. Possibilidades como por outros vetores, sexual, criminal e por secreção de marsupiais são consideradas excepcionais. A prevenção dos mecanismos alternativos, incluindo o congênito, está hoje consensuada: TRANSMISSÃO CONGÊNITA: detecção precoce do caso e seu tratamento específico. Se possível começar, no pré-natal com sorologia de gestantes. Quando viável, pesquisar parasitologicamente o RN de mães reagentes, tratando-se imediatamente os que resultarem positivos. Sendo negativos, sorologia convencional aos 8 meses de vida, tratando imediatamente os que estiverem reagentes. TRANSMISSÃO ACIDENTAL: Usar treinamento e equipamentos de proteção. Se acidente, desinfecção local, sorologia convencional e inicio de tratamento específico por dez dias. Revisão da sorologia em 30 dias, seguindo-se o tratamento até a dose total, no caso de reação positiva. TRANSPLANTES DE ÓRGÃOS: sorologia prévia no doador e receptor. Sendo o primeiro positivo e o segundo negativo, evitar o transplante ou tratar especificamente o doador por 10 dias antes da cirurgia e o receptor nos dez dias subsequentes à mesma. TRANSMISSÃO ORAL: de modo geral, higiene alimentar e cozimento de carnes de possíveis reservatórios. Hoje se recomenda a detecção precoce e tratamento imediato do caso, com intensa busca ativa entre os circunstantes mais próximos do paciente.

Vectorial, transfusion and congenital are considered the main transmission mechanisms in human Chagas disease. Alternative mechanisms are accidental, oral and by organ transplantation. Other hypothetic mechanisms could be by other vectors, sexual, criminal and by means of marsupial anal secretions. The present accorded strategies for prevention are: CONGENITAL: early case detection and immediate treatment. If possible, start during the pre natal period, throughout mothers serology, performing parasitological tests in the new born from positive women. For positive cases, immediate treatment; for those negative babies, conventional serology at the 8th month, treating specifically those with positive results. ACCIDENTAL TRANSMISSION: Rigorous training and utilization of protection equipments. IF accident occurs, immediate disinfection, conventional serology and beginning of specific treatment by ten days. Revision of the serology after 30 days: if positive, extend the treatment until the total dose (60 days or more). ORGAN TRANSPLANTATION: previous serology for donor and receptor. When the former is infected and the last negative, cancel the surgery or install the specific treatment by ten days before the surgery for the donor, followed by the receptor during ten days after the transplantation. ORAL TRANSMISSION: Specific measures are not available, food hygiene is recommended, including the cooking of meats delivered from possible reservoirs. Nowadays, the detection and immediate treatment of the case is recommended, followed by active research of new cases around the detected one.

Trend and Outcome of Korean Patients Receiving Overseas Solid Organ Transplantation between 1999 and 2005

The disparity between patients awaiting transplantation and available organs forced many patients to go overseas to receive a transplant. Few data concerning overseas transplantation in Korea are available and the Korea Society for Transplantation conducted a survey to evaluate the trend and outcome of overseas transplantation. The survey, conducted on June 2006, included 25 hospitals nationwide that followed up patients after receiving kidney transplant (KT) or liver transplant (LT) overseas. The number of KT increased from 6 in 2001 to 206 in 2005 and for LT from 1 to 261. The information about overseas transplant came mostly from other patients (57%). The mean cost for KT was dollar 21,000 and for LT dollar 47,000. Patients were admitted for 18.5 days for KT and 43.4 days for LT. Graft and patient survival was 96.8% and 96.5% for KT (median follow up 23.1 months). Complication occurred in 42.5% including surgical complication (5.3%), acute rejection (9.7%) and infection (21.5%). Patient survival for LT was 91.8% (median follow up 21.2 months). Complication occurred in 44.7% including 19.4% biliary complication. Overseas KT and LT increased rapidly from 2001 to 2005. Survival of patients and grafts was comparable to domestic organ transplantation, but had a high complication rate.

Trend and Outcome of Korean Patients Receiving Overseas Solid Organ Transplantation between 1999 and 2005

The disparity between patients awaiting transplantation and available organs forced many patients to go overseas to receive a transplant. Few data concerning overseas transplantation in Korea are available and the Korea Society for Transplantation conducted a survey to evaluate the trend and outcome of overseas transplantation. The survey, conducted on June 2006, included 25 hospitals nationwide that followed up patients after receiving kidney transplant (KT) or liver transplant (LT) overseas. The number of KT increased from 6 in 2001 to 206 in 2005 and for LT from 1 to 261. The information about overseas transplant came mostly from other patients (57%). The mean cost for KT was dollar 21,000 and for LT dollar 47,000. Patients were admitted for 18.5 days for KT and 43.4 days for LT. Graft and patient survival was 96.8% and 96.5% for KT (median follow up 23.1 months). Complication occurred in 42.5% including surgical complication (5.3%), acute rejection (9.7%) and infection (21.5%). Patient survival for LT was 91.8% (median follow up 21.2 months). Complication occurred in 44.7% including 19.4% biliary complication. Overseas KT and LT increased rapidly from 2001 to 2005. Survival of patients and grafts was comparable to domestic organ transplantation, but had a high complication rate.

Cáncer de piel no melanoma e inmunosupresión / Non-melanoma skin cancer and inmunosuppressive therapy

El cáncer de piel no melanoma es la neoplasia más frecuente en el ser humano, sin embargo su incidencia es aún mayor en individuos trasplantados usuarios de inmunosupresión prolongada, representado en ellos el 95 por ciento de los cánceres de piel, con un comportamiento más agresivo y mayor probabilidad de recidiva. A diferencia de la población general, en la cual el cáncer basocelular es el más común, en estos pacientes el carcinoma de células escamosas es el más habitual. El papel del tratamiento inmunosupresor en la génesis del cáncer de piel no melanoma es vastamente reconocido. Los cánceres de piel resultan tanto de una disminución de la actividad inmunológica, como de los efectos oncogénicos directos vinculados a algunos inmunosupresores. La carga tumoral específica parece estar vinculada con el tipo, dosis y duración de la inmunosupresión. En este artículo presentamos una revisión sistemática actualizada de la literatura acerca de esta interesante entidad patológica, con especial énfasis en la epidemiología, factores de riesgo, patogénesis y terapia.

Epidemiology of neglected tropical diseases in transplant recipients: review of the literature and experience of a Brazilian HSCT center / Epidemiologia das doenças tropicais negligenciadas em receptores de transplantes: revisão da literatura e experiência de um centro brasileiro

The rising success rate of solid organ (SOT) and haematopoietic stem cell transplantation (HSCT) and modern immunosuppression make transplants the first therapeutic option for many diseases affecting a considerable number of people worldwide. Consequently, developing countries have also grown their transplant programs and have started to face the impact of neglected tropical diseases (NTDs) in transplant recipients. We reviewed the literature data on the epidemiology of NTDs with greatest disease burden, which have affected transplant recipients in developing countries or may represent a threat to transplant recipients living in other regions. Tuberculosis, Leprosy, Chagas disease, Malaria, Leishmaniasis, Dengue, Yellow fever and Measles are the topics included in this review. In addition, we retrospectively revised the experience concerning the management of NTDs at the HSCT program of Amaral Carvalho Foundation, a public transplant program of the state of São Paulo, Brazil.

O sucesso crescente dos transplantes de órgãos sólidos (TOS) e de células tronco-hematopoiéticas (TCTH) e as novas drogas imunossupressoras fizeram dos transplantes a primeira opção terapêutica para muitas doenças que afetam milhares de pessoas em todo o mundo. Também os populosos países em desenvolvimento investiram no crescimento de seus programas de transplante e desde então começaram a vivenciar o impacto das doenças tropicais negligenciadas (DTNs) nestes pacientes. Revisamos os dados da literatura sobre a epidemiologia das DTNs de maior impacto clinico e social que afetam receptores de transplante de países em desenvolvimento, ou que podem representar um risco para receptores de transplante vivendo em outras regiões não afetadas por estas doenças. Tuberculose, hanseníase, doença de Chagas, malaria, leishmaniose, dengue, febre amarela e sarampo são os tópicos incluídos nesta revisão. Além disso, revisamos retrospectivamente a experiência referente ao manejo das DTNs do Serviço de Transplante de Medula Óssea da Fundação Amaral Carvalho, atualmente o maior centro de TCTH alogênico do Brasil.