engleski

HBV-OBI LOOK-BACK pro and contra?

HBV transmission from OBI donors to recipients is possible and proven. The efficiency of the transmission depends on infectious dose, donor’s and recipient’s HBs antibody titer and immunocompetence of the recipient. Since the introduction of ID-NAT test in Croatia the HBV-OBI look-back (LB) procedure is conducted for the recipients of previous donations for which subsequent testing of archived samples proved the presence of HBV DNA. Aims: Given the 1-year experience we aim to analyze the results of the conducted HBV-OBI LB procedures in order to make a decision whether HBV-OBI LB should or should not be conducted in this form. PROS: To get the answers related to infectivity of blood from HBV- OBI donors, specificity of recipient’s immune response to HBV infection, infection presentation and eventual lapses in pre-donation donors evaluation. CONS: To evaluate the meaning of the LB limitations, uncertainty of the interpretation of the recipients’ testing results in country of moderate HBV endemicity, impact on the blood safety perception and demanding LB organization. Methods: HBV-OBI donors were predominantly male (21/23), aged 43–67 years (58 M), ID-NAT and a-HBc positive with low anti- HBs titer (56.5%). All archived samples were anti-HBc and 39% ID-NAT positive with low HBV-DNA (11 < 20 IU/ ml, 2 > 100 (121, 133 IU/ml), 7 negative, 3 not tested. Serological pattern were matched in all samples with no dynamics.30 recipients were available, 29 had died, 4 not responded. 30% were immunosuppressed and 90% polytransfused. HBV infection with atypical seroprofile was detected in one recipient (FFP) who resolved infection rapidly. 5 recipients (3 FFP ; 2 RBC) was positive for anti-HBc (2/5 anti-HBs), while the two had only anti-HBs (not vaccinated). Results: PROS: 9.5% of the recipients have HBV markers, most of them are SSP recipients and immunocompromised which supports the possible HBV transmission. Atypical HBV profile without HBsAg expression and IgM anti-HBc is detected in one immunosuppressed recipient of plasma. No recipients have had the clinical signs of acute HBV infection. CONS: The lack of pre-transfusion blood sample, testing of recipients with time distance from 3 to 36 months, additional transfusions for which the archived samples have not been tested put the LP procedure away from it actual purpose. Since 90% of donors from OBI-LB have very low level of HBV- DNA, the ID-NAT negative archived samples turn to be positive in repeated testing which requires additional interpretations towards clinicians and results with negative impact on the blood safety perception. Conclusion: HBV-OBI LB were conducted partially which is caused by limited archive and unavailability of the recipients. Positive test results were interpreted with high level of uncertainty which is inappropriate with regards to its purpose and effort spent in conducting the LB. Therefore we believe that in the examination of the infectivity of OBI donor the recipients’ pre- transfusion as well as post-transfusion control samples, taken at certain time intervals depending on recipients’ immune capability should be ensured. It is feasible within the research project scope, but it is difficult in routine work circumstances. HBV-OBI LB pro or contra?

nije evidentirano

DOI: 10.1111/vox.12153