One window-period donation in two years of individual donor-nucleic acid test screening for hepatitis B, hepatitis C and human immunodeficiency virus

Abstract

ObjectiveTo describe general data on nucleic acid/serology testing and report the first hepatitis B-nucleic acid testing yield case of an immunized donor in Brazil. MethodsA total of 24,441 donations collected in 2010 and 2011 were submitted to individual nucleic acid testing for hepatitis B, hepatitis C and human immunodeficiency virus using the TaqMan(r) MPX kit (Roche) on the Cobas s201 platform, in addition to routine screening for serological markers. Nucleic acid testing-reactive donations were further evaluated by real-time polymerase chain reaction using Cobas AmpliPrep/Cobas TaqMan hepatitis B virus, hepatitis C virus and human immunodeficiency virus tests. ResultsThirty-two donations were reactive by nucleic acid testing, 31 were also serologically reactive and one first-time donor was identified as having hepatitis B in the window period. Follow-up samples showed increasing titers of anti-HBs rising from 19 UI/mL in the index donation to 109 IU/mL seven months later attributable to his vaccination history. Curiously, this donor was never reactive for HbsAg nor for anti-HBc. In the yield donation, he was concomitantly reactive for syphilis (enzyme immunoassay and fluorescent treponemal antibody-absorption; venereal disease research laboratory non-reactive). Overall, six donors (0.02%) were characterized as occult hepatitis B. A total of 35% of the confirmed (recombinant immunoblot assay positive) hepatitis C donations were nucleic acid testing non-reactive and no human immunodeficiency virus "elite controller" was identified.ConclusionThe yield rate (1:24,441; 95% confidence interval: 1:9,537 - 1:89,717) contrasts to the North American rate (1:410,540 donations) and strongly advocates the adoption of nucleic acid testing for hepatitis B in Brazil despite the increasing rate of anti-HBs reactive subjects due to the successful immunization program.

Occult hepatitis B virus infection in patients with leprosy

“…16,17 The prevalence of occult HBV infection is influenced by a number of factors, such as sensitivity of the technique used to detect the HBV DNA and epidemiological characteristics of the population, making it difficult to compare results of different studies. [18][19][20][21][22][23][24][25][26] The current study was the first in Brazil that investigated the occurrence of occult HBV infection in leprosy patients and identified occult infection in 5.3% of those tested. This frequency was lower than that reported in HIV/AIDS 19,20 patients (approximately 14%) or in patients with tuberculosis (coinfected or not with HIV) 24 in the same country.…”

“…On the other hand, the rate of occult HBV infection found in leprosy patients (5.3%) was higher than that reported in healthy candidates for blood donation in Brazil . Levi et al found occult infection in only 0.02% of potential donors using a high sensitivity nucleic acid amplification test (detection limit of 3.8 IU/mL), and Moresco et al identified occult HBV infection in 2.7% using real‐time PCR with a detection limit of 24 IU/mL. This result may suggest that leprosy patients are at higher risk of occult HBV infection compared with the general population.…”

“…This frequency was lower than that reported in HIV/AIDS patients (approximately 14%) or in patients with tuberculosis (coinfected or not with HIV) in the same country. On the other hand, the rate of occult HBV infection found in leprosy patients (5.3%) was higher than that reported in healthy candidates for blood donation in Brazil . Levi et al found occult infection in only 0.02% of potential donors using a high sensitivity nucleic acid amplification test (detection limit of 3.8 IU/mL), and Moresco et al identified occult HBV infection in 2.7% using real‐time PCR with a detection limit of 24 IU/mL.…”

“…Brazil is responsible for 13% of the new cases of leprosy in the world, but it is considered a country of “low” endemicity for HBV, with a prevalence of HBsAg estimated at 0.65% . The prevalence of occult HBV infection is influenced by a number of factors, such as sensitivity of the technique used to detect the HBV DNA and epidemiological characteristics of the population, making it difficult to compare results of different studies …”

Comment on: One window-period donation in two years of individual donor-nucleic acid test screening for hepatitis B, hepatitis C and human immunodeficiency virus

“…The article in this issue of the Revista Brasileira de Hematologia e Hemoterapia (RBHH) entitled One window-period donation in two years of individual donor-nucleic acid test screening for hepatitis B, hepatitis C and human immunodeficiency virus by Levi et al describes the first two years of screening for HIV RNA, HCV RNA and HBV DNA using ID NAAT in a small Brazilian blood center (8) . From a total of 24,441 donations, no additional yield was obtained for HIV and HCV and they showed a 35% clearance rate for HCV and no elite controllers for HIV.…”