Avaliação da Carga Viral do Vírus da Hepatite C (VHC) no Plasma Pobre em Plaquetas
Carregando...
Data
2019-02-27
Autores
Battistam, Daniel Contiero
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
A Hepatite C é uma doença hepática de etiologia viral cujo agente é o Vírus da Hepatite C (VHC). A infecção pelo vírus, na grande maioria dos casos evolui para a cronicidade, sendo, portanto, um problema de saúde pública devido ao seu grande potencial de evolução para cirrose e hepatocarcinoma. Portanto, atualmente é fundamental a utilização de testes moleculares como diagnóstico complementar e para o acompanhamento da doença no paciente infectado, assim como para a detecção cada vez mais precoce da infecção pelo VHC. Neste sentido, testes para a detecção de ácidos nucléicos podem ser utilizados para a detecção qualitativa e quantitativa do RNA-VHC no sangue dos pacientes, de modo a avaliar a dinâmica da infecção e definir a conduta terapêutica. Desta forma, o Ministério da Saúde adotou no Brasil uma metodologia baseada na Reação em Cadeia da Polimerase em Tempo Real (RT-qPCR) precedida de etapa de transcrição reversa para a detecção do material genético viral em amostras de plasma dos infectados. A presença do VHC está documentada em outros compartimentos biológicos como células mononucleares do sangue periférico (PBMC) e plaquetas, o que sugere que o protocolo atualmente adotado no Brasil pode superestimar o número de partículas virais ativas, visto que o plasma preparado para a realização desta análise contém uma grande quantidade de plaquetas em relação à contagem total dos indivíduos. Desta forma, a finalidade da execução deste projeto foi comparar a carga viral do VHC em pacientes cronicamente infectados levando-se em conta o protocolo atualmente empregado pelo SUS e outro modificado onde o plasma preparado é praticamente isento de plaquetas. Embora nenhuma diferença estatisticamente significativa tenha sido encontrada na comparação dos protocolos, as inferências estatísticas realizadas a partir dos resultados obtidos demonstraram que o genótipo viral parece, à primeira vista, ser capaz de influenciar a distribuição do VHC nos compartimentos extra-hepáticos, dependendo do tipo de protocolo utilizado. Apesar dos dados e da quantidade de pacientes analisados ainda não indicar de forma segura uma necessidade de mudança técnica no protocolo atual da Rede Nacional de Carga Viral do VHC, os achados deste trabalho sugerem que novos estudos devem ser prontamente realizados, de modo a adequar a conduta terapêutica e o prognóstico de cada paciente portador de Hepatite C.
Hepatitis C is a liver disease of viral etiology whose agent is Hepatitis C Virus (HCV). This virus infection, in the vast majority of cases, progresses to chronicity and is therefore a public health problem due to its great potential for progression to cirrhosis and hepatocarcinoma. Therefore, the use of molecular tests as a complementary diagnosis and disease control, as well as for early detection of HCV infection, is currently essential. In this sense, tests for the detection of nucleic acids can be used for the qualitative and quantitative detection of HCV RNA in the blood of the patients, in order to evaluate the dynamics of the infection and define the therapeutics. Thus the Brazilian Ministry of Health adopted a methodology based on the Real-Time Polymerase Chain Reaction (RT-qPCR) preceded by a reverse transcription step for the detection of the viral genetic material in plasma samples of infected individuals. The presence of HCV is well documented in other biological compartments such as peripheral blood mononuclear cells (PBMC) and platelets, suggesting that the protocol currently adopted in Brazil may overestimate the number of active viral particles, since the plasma samples prepared for this analysis contains a large amount of platelets. Thus, the purpose of this project was to compare the HCV viral load in chronically infected patients, taking into account the protocol currently used by the SUS and another one modified, where the plasma samples are practically free of platelets. Although no statistically significant difference was found in the comparison of the protocols, statistical inferences from the results showed that the viral genotype appears to influence the distribution of HCV in extra hepatic compartments, depending on the protocol. Although the data and the number of patients analyzed still do not indicate a need for a technical change in the current protocol of the National HCV Viral Load Network, the findings of this study suggest that new studies should be carried out promptly in order improve prognosis and treatment patients.
Hepatitis C is a liver disease of viral etiology whose agent is Hepatitis C Virus (HCV). This virus infection, in the vast majority of cases, progresses to chronicity and is therefore a public health problem due to its great potential for progression to cirrhosis and hepatocarcinoma. Therefore, the use of molecular tests as a complementary diagnosis and disease control, as well as for early detection of HCV infection, is currently essential. In this sense, tests for the detection of nucleic acids can be used for the qualitative and quantitative detection of HCV RNA in the blood of the patients, in order to evaluate the dynamics of the infection and define the therapeutics. Thus the Brazilian Ministry of Health adopted a methodology based on the Real-Time Polymerase Chain Reaction (RT-qPCR) preceded by a reverse transcription step for the detection of the viral genetic material in plasma samples of infected individuals. The presence of HCV is well documented in other biological compartments such as peripheral blood mononuclear cells (PBMC) and platelets, suggesting that the protocol currently adopted in Brazil may overestimate the number of active viral particles, since the plasma samples prepared for this analysis contains a large amount of platelets. Thus, the purpose of this project was to compare the HCV viral load in chronically infected patients, taking into account the protocol currently used by the SUS and another one modified, where the plasma samples are practically free of platelets. Although no statistically significant difference was found in the comparison of the protocols, statistical inferences from the results showed that the viral genotype appears to influence the distribution of HCV in extra hepatic compartments, depending on the protocol. Although the data and the number of patients analyzed still do not indicate a need for a technical change in the current protocol of the National HCV Viral Load Network, the findings of this study suggest that new studies should be carried out promptly in order improve prognosis and treatment patients.
Descrição
Palavras-chave
Plasma pobre em plaquetas, Carga Viral, Hepatite C, Platelet-poor plasma, Viral load, Hepatitis C