Prevalência de anti-HBc isolado em amostras do instituto Adolfo Lutz e hepatite B oculta após resposta vacinal em pacientes do ambulatório municipal de hepatites virais

Abstract

The presence of anti-HBc alone can have several meanings: false positive, healing immune window, delayed immunity or occult hepatitis B virus infection (OBI). In clinical practice, it is important and necessary to clarify the diagnosis to prevent transmission to the risk population such as hemodialysis patients, blood donors, transplant recipients and co-infected individuals with HIV and/or HCV. Objectives: The aim of the study was to determine the prevalence of anti-HBc alone and occult hepatitis B, respectively, in blood samples from Adolfo Lutz Institute - Regional Laboratory Center X - São José do Rio Preto (IAL - CLR X - SJRP) and patients from Municipal Ambulatory of Viral Hepatitis (AMHV) both from São José do Rio Preto city in the period from January 1st, 2009 to December 31st, 2014. Methods: The study population of IAL - CLR X - SJRP is from the region served by the 15th Health Regional Division (DRS), and the AMHV is a population screened for clarification, monitoring and treatment of viral hepatitis in the city. In this population with anti-HBc alone, patients were immunized against hepatitis B and the individuals without vaccine response were selected for the performance of HBV-DNA research for the diagnosis of occult hepatitis B. Results: During the study period, 6805 samples were evaluated without duplication in IAL - CLR X - SJRP, of these 624 samples had anti-HBc positive, and the prevalence of anti-HBc alone was 17.63% (110/624). In the AMHV, 940 patients anti-HBc isolated were evaluated, from these 816 (86.81%) were vaccinated and after the criterion of disregarding the vaccinated patients who did not have anti-HBs evaluated after vaccination (85 - 10.42%), 731 (89.58%) patients were considered for analysis of the vaccine response, and 568 (77.70%) presented seroconversion with anti-HBs positive and 163 (22.30%) non-seroconverted patients. The research of HBV-DNA was performed in 25.77% (42/163) patients without a vaccine response, finding a prevalence of occult hepatitis B (OBI) of 47.62% (20/42).The presence of antibodies to HIV and HCV was 25.40% and 13.25% in the blood samples IAL - CLR X - SJRP and in AMHV was 1.80% and 0.33%, respectively. Conclusion: The results show the occurrence of antiHBc alone in IAL - CLR X - SJRP and the need of monitoring this population. In AMHV, the vaccination was effective for most cases, which demonstrates the need of vaccine introduction as a routine in anti- HBc alone patients in the overall population. The occult hepatitis B was found in almost half of patients assessed without vaccine response.