RESUMO CONTEXTO: Os imunossupressores desempenham importante papel no transplante de órgãos sólidos, com o objetivo de evitar a rejeição aguda e crônica, aumentando o tempo de sobrevida do órgão e do paciente. No Brasil, em 2016, o transplante de fígado foi o 3° mais frequente, com um número de 1.880 transplantes, sendo 150 realizados no Rio Grande do Sul. OBJETIVO: Investigar a associação da variação dos níveis sanguíneos de tacrolimo com os desfechos clínicos, rejeição celular aguda tardia, óbito, sobrevida de paciente e enxerto em pacientes submetidos ao transplante hepático. MÉTODOS: Trata-se de um estudo longitudinal retrospectivo, no qual foram incluídos os pacientes submetidos ao transplante hepático adulto pelo grupo de transplante hepático na Irmandade Santa Casa de Misericórdia de Porto Alegre, no período de janeiro de 2006 a janeiro de 2013, e que fizeram o uso de tacrolimo como terapia imunossupressora. RESULTADOS: Dos 127 pacientes incluídos no estudo, a maioria era do gênero masculino (70,1%), caucasiana (86,4%), com idade entre 52 e 60 anos (33,9%). As associações de causas mais frequentes para transplante hepático foram vírus da hepatite C, carcinoma hepatocelular (24,4%) e álcool (15,7%). Um total de treze pacientes apresentaram rejeição celular aguda tardia (10,2%); destes, três tiveram dois episódios. O tempo médio de rejeição após o transplante hepático foi de 14 meses, variando de 8 a 33 meses. A sobrevida global foi de 8,98 anos. Em relação aos níveis sanguíneos de tacrolimo, foram identificados 52 pacientes com uma variação maior ou igual a dois desvios-padrão. Destes pacientes, oito tiveram rejeição, contudo, a associação não foi significativa (P=0,146). Foi encontrada uma associação significativa entre a variação maior ou igual a dois desvios-padrão nos níveis sanguíneos de tacrolimo com óbito (P=0,023) e sobrevida (P=0,019). Em relação ao acompanhamento de sobrevida do enxerto em cinco anos, estar dois desvios-padrão acima aumenta em 2,26 vezes o risco de perda do enxerto transplantado, e a cada unidade de aumento de desvio-padrão dos níveis sanguíneos de tacrolimo há um aumento de duas vezes no risco de perda do enxerto transplantado em 5 anos. CONCLUSÃO: O aumento do risco da perda do enxerto associado ao aumento da variação dos níveis sanguíneos de tacrolimo pode indicar a necessidade do acompanhamento mais rigoroso e prospectivo dos níveis sanguíneos de tacrolimo.

ABSTRACT BACKGROUND: Immunosuppressive drugs have important role in transplant of solid grafts, it aim avoid episodes of acute and chronic rejection and improving graft survival and patient survival. In Brazil, in 2016, liver transplantation was the third most frequent, with 1,880 transplants performed, of which 150 in Rio Grande do Sul. Several studies evaluated the association between variability in blood levels of immunosuppressive tacrolimus and late acute cellular graft rejection. OBJECTIVE: To investigate the association of tacrolimus blood levels with clinical outcomes late acute cellular rejection, death, patient survival and graft survival in patients undergoing liver transplantation. METHODS: This is a retrospective longitudinal study including patients submitted to adult liver transplantation by the Liver Transplantation Group in the Santa Casa de Misericórdia Hospital of Porto Alegre, from January 2006 to January 2013, and who used tacrolimus as immunosuppressive therapy. RESULTS: Of the 127 patients included in the study, the majority were male (70.1%), 52-60 years old (33.9%) at the transplant. The most frequent causes of liver transplantation in this series were hepatitis C virus and hepatocellular carcinoma (24.4%) and alcohol (15.7%). Thirteen patients had late acute cellular rejection (10.2%); of these, three had two episodes. Regarding severity classification, seven patients had mild late acute cellular rejection. The mean time of rejection after liver transplantation was 14 months (ranging from 8 to 33 months). Overall survival was 8.98 years. Regarding tacrolimus blood levels, 52 patients with a variation ≥2 standard deviations were identified. Of these patients, eight had rejection; however, the association was not significant (P=0.146). A significant association was found between variation ≥2 standard deviations in tacrolimus blood levels and death (P=0.023) and survival (P=0.019). Regarding 5-year follow-up of graft survival, being two standard deviations above increases by 2.26 times the risk of transplanted graft loss, and for each unit of increase of standard deviation of tacrolimus blood levels there is a two-fold increase in the risk of graft loss in 5 years. CONCLUSION: Increased risk of graft loss associated with increased standard deviations of tacrolimus blood levels may indicate the need for more rigorous and prospective monitoring of tacrolimus blood levels.

Direct-acting antivirals used in the treatment of hepatitis C have demonstrated high rates of efficacy, are well tolerated and considered safe. However, they are not free of drug interactions. To describe the effectiveness of hepatitis C treatment and the incidence and severity of potential drug interactions between drugs used during this treatment. A cross-sectional study with 148 patients who began treatment for hepatitis C between April and June 2016 in a specialized center in Brazil. Drug interactions were identified in the Truven Health Analytic/DynaMed Plus and Hep-C Interactions databases. Regarding treatment outcome, 93.9% of patients achieved SVR, 2.7% relapsed and 3.4% did not return after the end of the follow-up period. A total of 328 chronic diseases were identified (71 different diseases), and 88.5% of the patients had at least one chronic disease. The patients reported the use of 474 drugs (121 different drugs), with 3.2 drugs per patient on average. We identified 265 potential drug interactions, classified as important (6.0%), with clinical significance (20.7%) and without clinical significance or with insufficient data (69.4%). Cirrhotic patients had a higher average number of potential drug interactions than non-cirrhotic patients (2.51 x 0.79, p = 0.000). Hepatitis C treatment with direct-acting antivirals are effective and safe for most of patients.

Resumo Contexto Fatores genéticos podem ser responsáveis por parte das diferenças populacionais e interindividuais observadas em usuários de varfarina. Objetivos Identificar a ocorrência de polimorfismo dos genes CYP2C9 e VKORC1 em pacientes em uso de varfarina e relacionar esses perfis com a dose do medicamento e o tempo no intervalo terapêutico. Métodos Foram realizadas entrevistas mensais para a coleta de dados. Foram reunidos dados sobre características demográficas e medicamentos em uso, principalmente sobre varfarina, como motivo da prescrição e dose semanal. O tempo no intervalo terapêutico foi calculado como a porcentagem de dias com razão normalizada internacional entre os valores 2 e 3. Os genes CYP2C9 e VKORC1 foram analisados em laboratório de Genética Humana. Resultados Entre os participantes, 49 pacientes (74,2%) apresentaram polimorfismo dos genes CYP2C9 e/ou VKORC1; os 17 restantes (25,8%) não apresentaram esses polimorfismos. A dose média semanal de varfarina foi menor entre os que apresentaram polimorfismo para algum dos genes em comparação aos que não apresentaram, com diferença significativa (p = 0,035). O tempo no intervalo terapêutico médio também foi menor entre os pacientes com polimorfismo. Porém, não houve diferença significativa entre os dois grupos para essa variável (p = 0,438). Conclusões Foi observada associação entre os polimorfismos e a dose de varfarina utilizada pelos pacientes; no entanto, não houve associação com eventos adversos e o tempo de permanência na faixa terapêutica nessa amostra.

Abstract Background Genetic factors can be responsible for part of the populational and interindividual differences observed in warfarin users. Objectives To identify occurrence of polymorphisms of the CYP2C9 and VKORC1 genes in patients taking warfarin and relate these profiles to their medication dosages and the Time in Therapeutic Range (TTR). Methods Monthly interviews were conducted for data collection. Data were collected on demographic characteristics and medications in use, especially warfarin, including reason for prescription and weekly dose. TTR was calculated as the percentage of days with international normalized ratio (INR) between 2 and 3. The CYP2C9 and VKORC1 genes were analyzed at a Human Genetics Laboratory. Results 49 patients (74.2%) had polymorphisms of the CYP2C9 and/or VKORC1 genes; the remaining 17 (25.8%) did not have these polymorphisms. The average weekly dose of warfarin was lower among those who had a polymorphism for any of the genes compared to those who did not, with a significant difference (p = 0.035). The mean TTR was also lower among patients with polymorphism. However, the difference between the two groups was not significant for this variable (p = 0.438). Conclusions An association was observed between the polymorphisms and the warfarin doses taken by the patients. However, there was no association with adverse events or the time spent within the therapeutic range in this sample.