Pancreatic tuberculosis mimicking a neoplastic mass in an immunosuppressed patient who also presented adenopathy syndrome: Case report.

Introduction: Pancreatic tuberculosis is unusual, with an incidence reported to be less than 4,7 % worldwide. Case report: We report the case of a 32-year-old man recently diagnosed with HIV whose adenopathy syndrome was understudy. Lymph node cervical and bone marrow biopsies were performed without evidence of neoplastic infiltration, fungal infection, or tuberculosis. He arrived at the emergency room for acute band abdominal pain radiating to the back. Results: Contrast-enhanced abdominal computed tomography revealed a mass in the head of the pancreas which generates intra- and extrahepatic bile duct dilation. Serial sputum, PPD, Genexpert, bronchoscopy and ultrasound fine needle aspiration biopsy were negative for tuberculosis, with no evidence of microorganisms or malignancy; cultures results pending. A second biopsy was requested using a No. 19 needle reporting a necrotizing process with acid-fast bacilli, compatible with tuberculosis, and the pending cultures results were positive for the mycobacterium tuberculosis complex, confirming the diagnosis. Conclusion: Clinical awareness of pancreatic tuberculosis in immunosuppressed patients in our country, may lead to faster and accurate diagnosis study and management, using minimally invasive techniques as diagnostic tools.

Melanoma metastásico a vejiga / Metastatic melanoma to the bladder / Melanoma metastático na bexiga

Introducción. El compromiso tumoral metastásico del melanoma al tracto genitourinario es frecuente, pero, la metástasis a vejiga es rara, constituye menos del 2% de los casos. Sin embargo, en autopsias realizadas a pacientes con melanoma se ha encontrado metástasis en la vejiga en entre un 18% y un 37% de los casos, lo que la convierte en la segunda en incidencia posterior al adenocarcinoma gástrico. La media de supervivencia suele ser entre 6 - 7.5 meses. El objetivo de este trabajo es presentar el caso de un melanoma metastásico a vejiga, entidad poco frecuente y poco diagnosticada por ser la mayoría de las veces asintomática. Presentación del caso. Paciente femenina de 62 años, con antecedente de melanoma al nivel del primer artejo del pie, con manejo quirúrgico y farmacológico. Consultó por hematuria. La cistoscopia evidenció una lesión única sólida, eritematosa, con necrosis y fácil sangrado y se indicó realizar resección transuretral (RTU). La patología demostró compromiso por melanoma ulcerado metastásico. Se inició manejo de segunda línea (Pembrolizumab) y presentó progresión a miembros superiores y recaída a nivel vesical. La paciente falleció un año después. Discusión. Las metástasis de melanoma al tracto genitourinario son frecuentes, pero las metástasis vesicales aisladas son raras. El tratamiento suele ser RTU de la lesión, cistectomía, quimioterapia y radioterapia. La RTU es curativa para las lesiones restringidas al epitelio, aunque la cistectomía radical suele ser la terapia de elección ante un paciente con un tumor localizado. El Pembrolizumab ha demostrado aumentar la supervivencia. El pronóstico depende del tamaño y profundidad de la invasión. Conclusiones. El compromiso vesical metastásico es poco frecuente y diagnosticado, puede estar presente en pacientes con melanoma, síntomas irritativos urinarios no específicos y hematuria. Suele ser de mal pronóstico, y requiere de manejo quirúrgico asociado a manejo sistémico.

Introduction. Metastatic tumor compromise of melanoma to the genitourinary tract is frequent, but metastasis to the bladder is rare, representing less than 2% of cases. However, autopsies performed on patients with melanoma have found metastases in the bladder in 18-37% of cases, making it the second incidence after gastric adenocarcinoma. The median survival is usually 6 to 7.5 months. The objective of this work is to present the case of a metastatic melanoma to the bladder, a rare and underdiagnosed condition because most of the time it is asymptomatic. Case Presentation. 62-year-old female patient, with a history of melanoma at the level of the first toe, with surgical and pharmacological management. The reason for consultation was hematuria. Cystoscopy revealed a single solid, erythematous lesion with necrosis and easy bleeding, and a transurethral resection (TUR) was indicated. The pathology found compromise for metastatic ulcerated melanoma. Second-line treatment (Pembrolizumab) was started and presented progression to the upper limbs and relapse at the bladder level. The patient died a year later. Discussion. Melanoma metastases to the genitourinary tract are common, but isolated bladder metastases are rare. Treatment is usually TUR of the lesion, cystectomy, chemotherapy, and radiation therapy. TUR is curative for lesions restricted to the epithelium, although radical cystectomy is usually the therapy of choice in patients with a localized tumor. Pembrolizumab has been shown to increase survival. The prognosis depends on the size and depth of the invasion. Conclusions. Metastatic bladder compromise is rare and underdiagnosed, it may be present in patients with melanoma, non-specific urinary irritative symptoms, and hematuria. It tends to have a poor prognosis, and requires surgical management associated with systemic management.

Introdução. O comprometimento do tumor metastático do melanoma no trato geniturinário é comum, mas a metástase na bexiga é rara, constituindo menos de 2% dos casos. Entretanto, em autópsias realizadas em pacientes com melanoma, foi encontrada metástase na bexiga entre 18% e 37% dos casos, o que a torna a segunda em incidência após o adenocarcinoma gástrico. A média de sobrevivência é geralmente entre 6 - 7,5 meses. O objetivo deste trabalho é apresentar o caso de um melanoma metastático na bexiga, uma entidade pouco frequente e subdiagnosticada, pois na maioria das vezes é assintomática. Apresentação do caso. Paciente do sexo feminino, 62 anos, com antecedentes de melanoma no nível do hálux, com manejo cirúrgico e farmacológico. Ela consultou por hematúria. A cistoscopia revelou uma única lesão sólida, eritematosa com necrose e sangramento fácil, e foi indicada uma ressecção transuretral (RTU). A patologia mostrou comprometimento de melanoma ulceroso metastático. O tratamento de segunda linha (Pembrolizumab) foi iniciado e a patologia avançou para os membros superiores e uma recaída no nível da bexiga. A paciente morreu um ano depois. Discussão. As metástases de melanoma para o trato geniturinário são frequentes, mas as metástases vesicais isoladas são raras. O tratamento é geralmente RTU da lesão, cistectomia, quimioterapia e radioterapia. A RTU é curativa para lesões restritas ao epitélio, embora a cistectomia radical seja geralmente a terapia de escolha para um paciente com um tumor localizado. O Pembrolizumab demonstrou aumentar a sobrevivência. O prognóstico depende do tamanho e da profundidade da invasão. Conclusões. O comprometimento vesical metastático é raro e subdiagnosticado, pode estar presente em pacientes com melanoma, sintomas irritantes urinários não específicos e hematúria. Geralmente tem um prognóstico negativo e requer manejo cirúrgico em associação com manejo sistêmico.

Epicardial fat tissue, coronary arterial calcification and mortality in patients with advanced chronic kidney disease and hemodialysis. / Tejido graso epicárdico, calcificación arterial coronaria y mortalidad en pacientes con enfermedad renal crónica avanzada y hemodiálisis.

INTRODUCTION AND OBJECTIVES: Epicardial and mediastinal adipose tissue (EAT, MAT) are linked to metabolic syndrome and coronary artery disease. Patients with chronic kidney disease (CKD) have thicker EAT. We assessed if EAT and MAT could be associated with increased mortality and cardiovascular events in patients with advanced CKD and haemodialysis therapy. METHODS: A post-hoc study was performed. We analyzed a prospective series of 104 cases. EAT thickness was quantified by a multislice synchronized computed tomography (MSCT). RESULTS: The follow-up period was 112.68 (109.94 -115.42) months. The optimal cut-off point of EAT for prediction of total mortality was 11.45mm (92.86% and 43.75%). EAT thickness was associated with serum albumin levels, serum triglyceride levels, phosphorus and calcium phosphate product. The EAT was greater in haemodialysis patients compared to those with advanced CKD (P<.001). Patients with diabetes mellitus had greater EAT and MAT thickness (P=.018). At the end of follow up, the survival average time of patients with EAT thickness <11.45mm was 97.48 months vs. 76.65 months for thickness > 11.45mm (P=.007). CONCLUSIONS: A higher EAT and MAT thickness was associated with increased mortality. Furthermore, EAT was associated with lower free survival time to fatal and non-fatal cardiovascular events. The measurement of EAT and MAT by MSCT could be a prognostic tool to predict cardiovascular events and mortality risk in advanced CKD patients.

Epicardial fat tissue, coronary arterial calcification and mortality in patients with advanced chronic kidney disease and hemodialysis.

INTRODUCTION AND OBJECTIVES: Epicardial and mediastinal adipose tissue (EAT, MAT) are linked to metabolic syndrome and coronary artery disease. Patients with chronic kidney disease (CKD) have thicker EAT. We assessed if EAT and MAT could be associated with increased mortality and cardiovascular events in patients with advanced CKD and haemodialysis therapy. METHODS: A post-hoc study was performed. We analyzed a prospective series of 104 cases. EAT thickness was quantified by a multislice synchronized computed tomography (MSCT). RESULTS: The follow-up period was 112.68 (109.94-115.42) months. The optimal cut-off point of EAT for prediction of total mortality was 11.45 mm (92.86% and 43.75%). EAT thickness was associated with serum albumin levels, serum triglyceride levels, phosphorus and calcium phosphate product. The EAT was greater in haemodialysis patients compared to those with advanced CKD (P < .001). Patients with diabetes mellitus had greater EAT and MAT thickness (P = .018). At the end of follow up, the survival average time of patients with EAT thickness <11.45 mm was 97.48 months vs. 76.65 months for thickness > 11.45 mm (P = .007). CONCLUSIONS: A higher EAT and MAT thickness was associated with increased mortality. Furthermore, EAT was associated with lower free survival time to fatal and non-fatal cardiovascular events. The measurement of EAT and MAT by MSCT could be a prognostic tool to predict cardiovascular events and mortality risk in advanced CKD patients.

Glutathione S-Transferase T1 Mismatch Is a Risk Factor for Chronic Ductopenic Rejection of Liver Allografts.

The underlying causes of chronic rejection (CR) after liver transplantation (LT) are not completely known. The main aim of this study was to explore the involvement of the minor histocompatibility antigen glutathione S-transferase T1 (GSTT1) in CR. We retrospectively studied 611 patients who underwent LTs at University Hospital Virgen del Rocío between 2003 and 2016 with a median follow-up of 7.4 ± 4.2 years. The GSTT1 genotype was determined by polymerase chain reaction. We defined GSTT1 mismatch as a specific donor/recipient combination in which a recipient who was homozygous for the deletion allele received a transplant from a positive donor. The prevalence of CR in our whole cohort was 11.6% (71/611), and the prevalence in the GSTT1-mismatched group was 18.8% (16/85) versus 10.5% (55/526) in the GSTT1-matched group. In the cyclosporine A (CsA) group, the prevalence was 26.3% (26/99), much higher than the 8.8% (45/512) observed in the tacrolimus (Tac) group. For statistical analysis, the patients were distributed into 2 groups: group 1, regarded as GSTT1 mismatched, which included the donor (D)+/recipient (R)- allelic combination; and group 2, regarded as GSTT1 matched, which included the other allelic combinations of D+/R+, D-/R-, and D-/R+. All relevant clinical information was collected, and a diagnosis of CR was always confirmed by liver biopsy. GSTT1 mismatch (hazard ratio [HR], 1.99; 95% confidence interval [CI], 1.08-3.66; P = 0.03) and use of CsA/Tac (P < 0.001) were independent risk factors for CR. CR increased the risk of mortality (HR, 2; 95% CI, 1.2-3.6; P = 0.01). Out of the 71 CR patients, 12 (16.9%) needed retransplantation. In conclusion, the GSTT1 D+/R- allelic mismatch is an independent risk factor for CR. A long follow-up of LT patients is recommended because the incidence of CR in adults seems to be underestimated.

Computer-Assisted Definition of the Inflammatory Infiltrates in Patients With Different Categories of Banff Kidney Allograft Rejection.

Currently, the diagnosis of kidney allograft rejection relies on individual histological assessments made by expert pathologists according to the Banff classification. In this study, we applied new Computer-Assisted System Technology (newCAST™) by Visiopharm® with the aim of identifying and quantifying the immune cells in inflammatory infiltrates. We searched for distinctive cellular profiles that could be assigned to each rejection category of the Banff schema: antibody-mediated rejection (active and chronic active), borderline, T cell-mediated rejection (TCMR), and mixed rejection. This study was performed with 49 biopsy samples, 42 from patients with rejection and 7 from patients with clinical signs of dysfunction but an absence of histological findings of rejection. Plasma cells, B and T lymphocytes, natural killer cells, and macrophages, with a special focus on the M1 and M2 subsets, were studied. A major difference among the Banff rejection groups was in the total amount of cells/mm2 tissue. Principal component analysis identified some distinctive associations. The borderline category grouped with CD4+ lymphocytes and M1 macrophages, and active antibody-mediated rejection (aAMR) clustered with natural killer cells. Despite these findings, the search for characteristic profiles linked to the rejection types proved to be a very difficult task since the cellular composition varied significantly among individuals within the same diagnostic category. The results of this study will be analyzed from the perspective of reconciling the classic way of diagnosing rejection and the immune situation "in situ" at the time of diagnosis.

Rethinking de novo immune hepatitis, an old concept for liver allograft rejection: Relevance of glutathione S-transferase T1 mismatch.

Antibody-mediated rejection (AMR) in liver transplantation has long been underestimated. The concept of the liver as an organ susceptible to AMR has emerged in recent years, not only in the context of the major histocompatibility complex with the presence of HLA donor-specific antibodies, but also with antigens regarded as "minor", whose role in AMR has been demonstrated. Among them, antibodies against glutathione S-transferase T1 have been found in 100% of patients with de novo autoimmune hepatitis (dnAIH) when studied. In its latest update, the Banff Working Group for liver allograft pathology proposed replacing the term dnAIH with plasma cell (PC)-rich rejection. Antibodies to glutathione S-transferase T1 (GSTT1) in null recipients of GSTT1 positive donors have been included as a contributory but nonessential feature of the diagnosis of PC-rich rejection. Also in this update, non-organ-specific anti-nuclear or smooth muscle autoantibodies are no longer included as diagnostic criteria. Although initially found in a proportion of patients with PC-rich rejection, the presence of autoantibodies is misleading since they are not disease-specific and appear in many different contexts as bystanders. The cellular types and proportions of the inflammatory infiltrates in diagnostic biopsies have been studied in detail very recently. PC-rich rejection biopsies present a characteristic cellular profile with a predominance of T lymphocytes and a high proportion of PCs, close to 30%, of which 16.48% are IgG4+. New data on the relevance of GSTT1-specific T lymphocytes to PC-rich rejection will be discussed in this review.

Identification of the cellular components involved in de novo immune hepatitis: a quantitative immunohistochemical analysis.

BACKGROUND: Diagnosis of de novo immune hepatitis (dnIH) after liver transplantation relies on biopsy findings, with an abundance of plasma cells (PCs) in the inflammatory infiltrates a hallmark of the disease. Very little is known about what other types of immune cells exist in the infiltrates mainly located in the portal areas of the liver tissue. METHODS: We analyzed the composition of T cells, B cells, PCs, and macrophages in the liver biopsies of 12 patients with dnIH, 9 of them obtained at the time of diagnosis. For comparison, biopsies from 9 patients with chronic rejection (CR) were included in the study. The results were analyzed by a computer-assisted stereology quantification method. RESULTS: The major components of the infiltrates in the portal areas were CD3+ T lymphocytes in both groups, with 36.6% in the dnIH group versus 49.4% in the CR group. CD20+ B lymphocytes represented 14.9% in the dnIH group and 29.1% in the CR group. Macrophage levels were very similar in the dnIH and CR group (19.7% versus 16.8%, respectively). PCs were much less represented in CR biopsies than those from the dnIH group (mean value of 4.7% versus 28.8%). CONCLUSION: In conclusion, the determination of a characteristic cellular profile could be an important tool for a more reliable diagnosis of dnIH, in support of the histological evaluation made by the pathologist, which in most cases is challenging. Recognition of this condition is crucial because it leads to graft failure if left untreated.

De novo recipient-specific Glutathione S-transferase T1 antibody development after HLA-identical hematopoietic cell transplantation.

Donor-specific antibodies against Glutathione S-transferase T1 (GSTT1) have been associated with de novo immune hepatitis after liver transplantation. These antibodies have also been found very early in allo-HCT associated with acute hepatic GvHD but in all the cases the donor cells had experienced previous priming through pregnancies. It remained to be explored whether or not primary recognition of the antigen occurs after HCT and what could be the consequences in the long term outcome. We genotyped a cohort of 68 HCT patients and found 11 with the GSTT1 null donor/positive recipient mismatch. After testing 114 serum samples, we found a unique case of a 33-year-old patient transplanted from his HLA-identical sibling donor in which IgG GSTT1 antibodies were detected for the first time on day +178. After stimulation of peripheral blood mononuclear cells with GSTT1 peptides we could demonstrate that this patient also had GSTT1-specific T lymphocytes that became activated upon exposure to the GSTT1 antigen. In this report, we describe the first case in which simultaneous T and B cell response against GSTT1 is developed in HCT although the clinical consequences in GvHD are still unclear.

Malacoplaquia renal. Presentación de caso / Renal Malakoplakia. Case report

Introducción: La malacoplaquia es una enfermedad granulomatosa multisistémica crónica caracterizada por una o múltiples placas blancas en varios órganos del cuerpo, precedida por alguna infección crónica bacteriana. En la mayoría de los casos estudiados se encuentra que la E. Coli contribuye en aproximadamente el 80 % de ellos. Objetivo: Dar a conocer la existencia de esta enfermedad y sus características mediante una revisión de tema, y exponer un caso de malacoplaquia renal en una mujer de 65 años de edad con múltiples comorbilidades asociadas a dicha entidad; se describe la utilización de los métodos diagnósticos, así como su desenlace. Discusión: La malacoplaquia es una patología que se encuentra frecuentemente en el tejido urinario, a pesar de que puede desarrollarse en otros órganos. Su etiopatología no ha sido totalmente explicada; sin embargo, se asume que se da por un defecto en la actividad fagolisosomal, al parecer por alteración en la concentración de guanosín monofosfato cíclico intracelular (cGMP) en macrófagos y monocitos. Los pacientes que cursan con esta patología pueden ser asintomáticos o presentar síntomas inespecíficos. Conclusión: La malacoplaquia es una entidad que, aunque poco frecuente en la población general, debe tenerse en cuenta cuando existe compromiso uni o multifocal del parénquima renal en pacientes con factores de riesgo. Las imágenes pueden no ser concluyentes y hacer sospechar patología tumoral; sin embargo, el estudio histopatológico de la muestra permite un diagnóstico definitivo, lo cual les da la oportunidad a los pacientes de recibir manejo oportuno con excelentes resultados.

Introduction: Malakoplakia is a chronic multisystemic granulomatous disease characterized by the presence of one or multiple white plaques in various organs of the body, preceded by some chronic bacterial infection. In most reported cases it is found that E. coli contributes in approximately 80% of cases. Objective: The objective of this article is to show a case report of this disease and its characteristics through a review of the subject. We present a case of renal Malakoplakia in a 65-year-old woman with multiple comorbidities associated with this entity. We emphasize on the use of the diagnostic methods, as well as the outcome. Discussion: Malakoplakia is a pathology that is usually found in the urinary tissue, although it may develop in other organs. Its cause has not been fully explained and it is assumed to be due to a defect in phagolysosome activity, apparently by alteration in the concentration of intracellular cyclic guanosine monophosphate (Cgmp) in macrophages and monocytes. Patients with this pathology may be asymptomatic or have non-specific symptoms. Conclusion: Malakoplakia is an entity that although rare in the general population should be taken into account when there is uni or multifocal involvement of the renal parenchyma in patients with the potential risk where the role of imaging is to provide a first work-up of the extension, with the final work-up taking place through histopathological studies, giving patients the opportunity to receive timely treatment with excellent results.

T-cell allorecognition of donor glutathione S-transferase T1 in plasma cell-rich rejection.

AIM: To investigate the role of glutathione S-transferase T1 donor-specific T lymphocytes in plasma cell-rich rejection of liver allografts. METHODS: The study group included 22 liver transplant patients. Among them, 18 patients were mismatched for the glutathione S-transferase T1 (GSTT1) alleles (don+/rec-), and 4 were matched (don+/rec+). Seven of the mismatched patients produced anti-GSTT1 antibodies and developed plasma cell-rich rejection (former de novo immune hepatitis). For the detection of specific T lymphocytes, peripheral blood mononuclear cells were collected and stored in liquid nitrogen. The memory T cell response was studied by adding to the cell cultures to a mix of 39 custom-made, 15-mer overlapping peptides, which covered the entire GSTT1 amino acid sequence. The specific cellular response to peptides was analyzed by flow cytometry using the markers CD8, CD4, IL-4 and IFNγ. RESULTS: Activation of CD8+ T cells with different peptides was observed exclusively in the group of patients with plasma-cell rich rejection (3 out of 7), with production of IL-4 and/or IFNγ at a rate of 1%-4.92% depending on the peptides. The CD4+ response was most common and not exclusive for patients with the disease, where 5 out of 7 showed percentages of activated cells from 1.24% to 31.34%. Additionally, two patients without the disease but with the mismatch had cells that became stimulated with some peptides (1.45%-5.18%). Highly unexpected was the finding of a double positive CD4+CD8low T cell population that showed the highest degree of activation with some of the peptides in 7 patients with the mismatch, in 4 patients with plasma cell-rich rejection and in 3 patients without the disease. Unfortunately, CD4+CD8low cells represent 1% of the total number of lymphocytes, and stimulation could not be analyzed in 9 patients due to the low number of gated cells. Cells from the 4 patients included as controls did not show activation with any of the peptides. CONCLUSION: Patients with GSTT1 mismatch can develop a specific T-cell response, but the potential role of this response in the pathogenesis of plasma cell-rich rejection is unknown.

Hemoptisis relacionada a una aspergilosis pulmonar cavitaria cónica: presentación de un caso / Hemoptysis related to chronic cavitary aspergillosis of the lung: case report

RESUMEN Introducción: la aspergilosis pulmonar crónica es una patología infrecuente, su prevalencia aumenta en asociación con alteraciones estructurales, esto resalta la importancia de su conocimiento teniendo en cuenta la elevada incidencia de tuberculosis en Colombia. Por el carácter angioinvasivo del hongo la posibilidad de desarrollar hemoptisis es alta, pudiendo llegar a comprometer la vida de quien la padece. Objetivo: estudiar la forma de presentación y abordaje diagnóstico de la aspergilosis y su asociación con secuelas de tuberculosis pulmonar. Presentación de caso: se presenta el caso de un paciente masculino de 44 años, con secuelas pulmonares por tuberculosis, que requirió hospitalización por hemoptisis recurrente; con hallazgos imagenológicos sugestivos de aspergilosis pulmonar, requirió estabilización clínica, embolización arterial selectiva y resección de la lesión. Conclusión: la aspergilosis es una enfermedad inusual y se requiere de la integración de aspectos clínicos e imagenológicos representativos para hacer un diagnóstico acertado. MÉD.UIS. 2017;30(1):79-86.

ABSTRACT Introduction: the chronic pulmonary aspergillosis is an uncommon condition, its prevalence increases in association with structural alterations, this highlights the importance of its knowledge bearing in mind the high incident of tuberculosis in Colombia. for the angioinvasive behavior of the fungus, the possibility of developing hemoptysis is high even life threatening. Objective: to study the form of presentation and diagnostic approach of the aspergilosis and his association with sequels of pulmonary tuberculosis. Case Report: we present a case of a 44-year-old masculine patient, with pulmonary sequels for tuberculosis who required hospitalization because of recurring hemoptysis; some imagenologic findings were found suggesting of pulmonary aspergillosis, he required clinical stabilization, selective arterial embolization and finally resection of the lesion. Conclusion: the aspergillosis is an unusual disease and requires integration of non-accurate clinical aspects and some representative imagenologic findings to make a proper diagnostic. MÉD.UIS. 2017;30(1):79-86.

IgG subclass profile among anti-Glutathione S-transferase T1 antibodies in post-transplant de novo immune hepatitis.

Although the pathogenic pathways leading to de novo immune hepatitis (IH) are not completely understood, we have shown strong evidences of an antidonor response against Glutathione S-transferase T1 (GSTT1), an antigen exclusively expressed in the donor liver. The first sign of this process is the production of GSTT1 antibodies that, in 25% of the cases, will precede de novo IH. Because the presence of the antibodies is not sufficient to trigger the disease, we aimed to study GSTT1 IgG subclasses in a group of 18 liver transplant patients, 12 that developed de novo IH and 6 that remained free of disease. Surprisingly, the predominant subclasses were IgG1-GSTT 1 and IgG4-GSTT 1. The presence of IgG4-expressing plasma cells was also investigated in 10 available liver biopsies. Six biopsies coinciding with diagnosis showed a mean value of 32.8 IgG4+ plasma cells/hpf vs. 5.55 in patients without the disease. We have not found a distinctive GSTT1-IgG profile in patients with de novo IH, but the ratio IgG1-GSTT 1 /IgG4-GSTT 1 in samples from close to the time of diagnosis seemed to be important. The novel finding of abundant IgG4-GSTT 1 in liver transplantation is intriguing, but their possible role in pathogenesis of de novo IH remains unknown.

Mismatch on glutathione S-transferase T1 increases the risk of graft-versus-host disease and mortality after allogeneic stem cell transplantation.

Several drug-metabolizing enzymes, preferentially expressed in the liver, have the potential to act as minor histocompatibility antigens. In the present study, we analyzed the impact of glutathione S-transferase T1 (GSTT1), glutathione S-transferase M1, glutathione S-transferase P1, and UDP glucuronosyl transferase 2B17 (UGT2B17) disparities on the outcome of 125 patients undergoing allogeneic hematopoietic stem cell transplantation. Grades 2 to 4 acute graft-versus-host disease (aGVHD) developed in 56.2% versus 73.3% of GSTT1-matched versus mismatched patients (P = .048). Remarkably, 8.6% GSTT1-matched patients developed grades 2 to 4 liver aGVHD, compared with 36.8% among GSTT1-mismatched recipients (P < .001). Regarding chronic graft-versus-host disease (cGVHD), 34.8% versus 70.7% matched versus mismatched patients developed overall cGVHD (P = .038) and 16.3% versus 48% developed hepatic cGVHD (P = .006). We also found a strong association between the UGT2B17 mismatch and the risk of severe aGVHD (P = .001), especially with gut involvement (P < .001). Most striking was the influence of the GSTT1 mismatch on nonrelapse mortality (26.8% versus 52.6%, P = .031) and overall survival (62% versus 36.9%, P = .045). In summary, UGT2B17 and GSTT1 mismatch are risk factors for the development of GVHD and the latter also influences on mortality and survival after allogeneic transplantation from HLA-identical donors.

Clinical relevance of GSTT1 mismatch in solid organ and hematopoietic stem cell transplantation.

Since 2001, year in which Glutathione S-transferase theta class 1 (GSTT1) gene appeared to be related to the occurrence of de novo immune hepatitis after liver transplantation, this gene with two allelic variants, GSTT1(∗)A (wild type copy) and GSTT1(∗)0 (deletion copy), has emerged as a potent histocompatibility antigen. Namely, a donor-recipient liver graft combination of a GSTT1-negative recipient (homozygous for GSTT1(∗)0) and a GSTT1-positive donor results, very frequently, in the appearance of a severe immune-related graft hepatitis with production of IgG anti-GSTT1 antibodies. In kidney transplantation, GSTT1 donor-recipient mismatch is also associated with production of anti-GSTT1 antibodies and antibody-related rejection episodes with C4d deposition in graft biopsy. The more recent discovery of anti-GSTT1 antibodies in hematopoietic stem cell transplantation, clearly confirms a role of GSTT1 as histocompatibility antigen in this setting. Interestingly, the consequences of GSTT1 mismatch might be either rejection or graft-versus-host disease, depending on the GSTT1 mismatch's sense of direction. The involvement of GSTT1 in immunological allo-recognition is unquestionable although there are still many aspects that remain to be explored.

Influence of glutathione S-transferase T1 donor/recipient mismatch and anti-GSTT1 antibodies in hepatic graft-versus-host-disease.

B cell responses to minor histocompatibility antigens (mHags) have not been extensively studied after allogeneic hematopoietic stem cell transplantation (HSCT). Glutathione S-transferase T1 (GSTT1) is a drug metabolizing enzyme encoded by a single gene that is highly expressed in liver and kidney. Anti-GSTT1 antibodies have been described in the context of antibody-mediated rejection in kidney and liver transplantation, due to a mismatch between donor and recipient. The aim of the present study was to investigate the specific immune response against GSTT1 in HSCT with production of antibodies and their influence in the development of hepatic graft-versus-host-disease (GVHD). Forty patients and their respective donors were included in the study. The median follow-up time was 35.6 months (range 0.6-76 months) and a total of 349 serum samples were tested for the presence of anti-GSTT1 antibodies by ELISA test. Statistical analysis was performed by defining the GSTT1 null donor/positive recipient as mismatch compared with the other three genetic combinations regarded as GSTT1-matched. Antibodies were found in three patients within the group of null donor/positive recipient and one within the null/null group. Development of liver GVHD, particularly its acute form, was highly associated with the GSTT1-mismatch (P=0.0178) and with the presence of post-transplant anti-GSTT1 antibodies (P=0.0076). We conclude that GSTT1 could be considered as a new mHag in hepatic GVHD. The fact that three donors were parous females and the rapid production of antibodies after HSCT suggests the existence in the graft of memory B-cells specific for the GSTT1 antigen.

Antibodies against heterogeneous nuclear ribonucleoprotein K in patients with cardiac allograft vasculopathy.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is the most serious long-term complication after cardiac transplantation. T-cell-mediated immune response has been implicated as the central mechanism for this form of graft rejection, but the role of humoral immunity is still controversial. METHODS: This study investigated whether human leukocyte antigen (HLA) and non-HLA antibodies are associated with CAV and if their presence can be used to identify patients at high risk of developing CAV. Diagnosis of CAV was made by angiography and intravascular ultrasound (IVUS) technology. Sera from 48 heart transplant recipients were assessed for the presence of antibodies. RESULTS: Although anti-HLA or anti-major histocompatibility complex class I chain-related gene A (MICA) antibodies in patients with or without CAV were not statistically different, heterogeneous nuclear ribonucleoprotein K (hnRNP-K) was identified as a new antigenic target after the screening of a human coronary artery smooth muscle cells complementary DNA (cDNA) expression library with a serum sample from a CAV patient. Four years after transplantation, presence of anti-hnRNP-K antibodies was significantly higher in the IVUS-defined CAV group (85.3%) and angiography-defined CAV patients (90.5%) compared with the non-CAV group (p < 0.0001 and p = 0.0023 respectively). CONCLUSIONS: The presence of anti-hnRNP-K antibodies 4 years after the transplant is statistically associated with CAV disease, regardless of the diagnostic technique. Therefore, prospective detection of these antibodies could be proposed as a helpful biomarker in CAV diagnosis.