Hepatitis B virus infection among oncohematologic disease patients in Central Brazil: prevalence, risk factors and immunization.

INTRODUCTION: Carriers of oncohematological diseases are at high risk for hepatitis B virus (HBV) infection. OBJECTIVE AND METHOD: To investigate the epidemiology of HBV infection in Goiânia, Central Brazil, 322 individuals with oncohematological diseases (leukemias, Hodgkin lymphoma and non-Hodgkin lymphoma) were interviewed and blood samples were collected for the detection of serological markers of HBV-DNA by polymerase chain reaction (PCR). Medical records of participants were also reviewed. RESULTS: Non-Hodgkin's lymphomas (n=99) and chronic myeloid leukemia (n=108) were the most frequent oncohematological diseases. The overall prevalence of HBV was 13.97% (45/322). Of the total participants, 8.69% (28/322) presented isolated positivity for anti-HBs, suggesting low vaccine coverage. HBV-DNA was detected in 25% (1/4) of HBsAg positive samples and in 25% (3/12) of anti-HBc isolated, suggesting HBV occult infection. All samples were identified as subgenotype A1. Entries in patient records and the findings of this investigation suggest anti-HBc seroconversion during oncologic treatment. Age 50 years or over and use of a central catheter during therapy were associated with HBV exposure. CONCLUSION: The low frequency of hepatitis B immunized individuals, detection of HBV DNA in HBsAg negative samples, and the suggestion of HBV exposure during treatment evidenced the potential for health-related viral dissemination in people with oncohematological diseases in our region, reinforcing the importance of serological monitoring, vaccination against hepatitis B, and adoption of strict infection control measures in these individuals.

Tissue residue depletion of moxidectin in lambs (Ovis aries) following subcutaneous administration.

To date, a tissue depletion study of moxidectin (MOX) in lambs is not available. Thus, considering that lamb meat is of great commercial interest in the world, the aim of the present study was to determine the residue levels of MOX in lamb target-tissues (muscle, liver, kidney and fat) and subsequently calculate the MOX withdrawal period. For this purpose, the target-tissues were analysed by ultra-high-performance liquid chromatography-tandem mass spectrometry. Method validation was performed based on Commission Decision 2002/657/EC and VICH GL49. To quantify the analyte, matrix-matched analytical curves were constructed with spiked blank tissues. The limits of detection and quantitation were 1.5 and 5 ng g-1, respectively, for all matrices. The linearity, decision limit, detection capability accuracy and inter- and intra-day precision of the method are reported. The lambs were treated with a single subcutaneous dose of 0.2 mg MOX kg-1 body weight and were slaughtered in accordance with accepted animal care protocols. Samples of target-tissues were collected on 2, 4, 7, 14, 28 and 42 days after MOX administration. During the whole study, the highest drug residue level occurred in the fat. For the other target-tissues (muscle, liver and kidney), MOX concentrations were below the maximum residue limit (MRL). Considering the MRL value of 500 µg kg-1 for MOX residues in sheep fat, our results in lambs allowed the estimation of a MOX withdrawal period of 31 days. This indicates that the withdrawal period established for MOX in adult sheep (28 days) does not apply for lambs.

Hepatitis B virus infection among oncohematologic disease patients in Central Brazil: prevalence, risk factors and immunization

ABSTRACT Introduction: Carriers of oncohematological diseases are at high risk for hepatitis B virus (HBV) infection. Objective and method: To investigate the epidemiology of HBV infection in Goiânia, Central Brazil, 322 individuals with oncohematological diseases (leukemias, Hodgkin lymphoma and non-Hodgkin lymphoma) were interviewed and blood samples were collected for the detection of serological markers of HBV-DNA by polymerase chain reaction (PCR). Medical records of participants were also reviewed. Results: Non-Hodgkin's lymphomas (n = 99) and chronic myeloid leukemia (n = 108) were the most frequent oncohematological diseases. The overall prevalence of HBV was 13.97% (45/322). Of the total participants, 8.69% (28/322) presented isolated positivity for anti-HBs, suggesting low vaccine coverage. HBV-DNA was detected in 25% (1/4) of HBsAg positive samples and in 25% (3/12) of anti-HBc isolated, suggesting HBV occult infection. All samples were identified as subgenotype A1. Entries in patient records and the findings of this investigation suggest anti-HBc seroconversion during oncologic treatment. Age 50 years or over and use of a central catheter during therapy were associated with HBV exposure. Conclusion: The low frequency of hepatitis B immunized individuals, detection of HBV DNA in HBsAg negative samples, and the suggestion of HBV exposure during treatment evidenced the potential for health-related viral dissemination in people with oncohematological diseases in our region, reinforcing the importance of serological monitoring, vaccination against hepatitis B, and adoption of strict infection control measures in these individuals.