Infecção oculta pelo vírus da Hepatite B em portadores de Hepatite C crônica e pacientes em situação de imunodepressão acompanhados em serviços de referência em Belo Horizonte

Abstract

Occult hepatitis B virus (HBV) infection is characterized by the presence of HBV DNA with undetectable surface antigen (HBsAg). It has been documented in groups at high risk of HBV infection, as well as in immunosuppressed individuals or patients with history of liver disease. Its prevalence and clinical relevance remain undefined. This study was conducted to determine the frequency of seropositive occult HBV infection in patients with chronic hepatitis C, solid malignancies, autoimmune rheumatic diseases, chronic kidney disease (CKD) on hemodialysis, HIV infection and hemoglobinopathies SS/SC in use of hydroxyurea. The study had also the objective of identifying possible demographic, epidemiological, clinical, and laboratory factors related to its occurrence. From March 2013 to September 2014, adult patients in referral centers in Belo Horizonte, with positive results for total anti-HBc and/or IgG and negative results for HBsAg in serum were investigated for the detection of HBV DNA in a single blood sample. Two hundred and thirty patients were studied and occult hepatitis B infection was found in 9.7% of patients with hepatitis C (1/31), 8.3% of those with solid malignancies (1/12), 1.1 % of CKD patients on hemodialysis (1/88), 8.9% of HIV patients (4/45) and 26.1% of patients with hemoglobinopathies SS/SC in use of hydroxyurea (6/23). No cases of occult HBV infection were identified among the 31 carriers of rheumatic diseases. Among patients with chronic hepatitis C, liver cirrhosis showed a tendency to be associated with the detection of serum HBV DNA (p = 0.064). In univariate analysis, diagnosis of hemoglobinopathies SS/SC was associated with detection of HBV DNA (p = 0.001) and being in hemodialysis was inversely associated with it (p = 0.006). In multivariate analysis, occult HBV infection was associated with history of alcohol abuse (OR 5.35, 95% CI 1.45 to 19.73) and with the diagnosis of hemoglobinopathies SS/SC (OR 13, 71, 95% CI 3.56 to 52.76). Another multivariate analysis revealed that blood transfusion was related to occult HBV infection only in patients with hemoglobinopathies (OR 13.75, 95% CI 2.83 to 66.87). The association between transfusion and HBV DNA detection was not significant in patients without hemoglobinopathies (OR 95 1.83, 0.29 - 11.62). The data suggest that factors related to hemoglobinopathy, and not to blood transfusion, are associated to a increased chance of HBV DNA detection.This is the first study to investigate the presence of occult HBV infection in patients with hemoglobinopathies SS/SC, the first Brazilian study evaluating this condition among patients with rheumatic diseases and solid malignancies and the first to locally evaluate its frequency in specific populations. The highest frequency of cases among patients with hemoglobinopathies SS/SC, the greater chance of diagnosis in patients with hemoglobinopathy and it those with a history of alcohol abuse, and the trend of association with cirrhosis among patients with chronic hepatitis C suggest that different mechanisms of liver injury may be involved in the detection of HBV DNA. Further prospective studies with larger number of cases, clinical follow-up and serial measurements of HBV DNA are required to better define the prevalence and clinical relevance of occult HBV infection.