Dried blood spot samples can be used to detect and quantify hepatitis B surface antibody (anti-HBs) among patients infected with HIV, according to results published in the Journal of Medical Virology.
This new detection tool has the potential to increase patients’ access to diagnosis and vaccination.
The study included HIV-positive (n=56) and HIV-negative participants (n=99). Participants provided serum and dried blood spot samples. The researchers used commercial enzyme immunoassays (HBsAg One, Radim, Italy; ETI-AB-COREK PLUS; Diasorin, Sluggia, Italy; ETI-AB-AUK, Diasorin; Vironostika HIV Uni-Form II Ag/Ab, Bio-Merieux, Boxtel, The Netherlands) to test for anti-HBs from serum samples. For dried blood spot samples, they used a commercial enzyme immunoassays (ETI-AB-AUK, Diasorin).
The sensitivity of anti-HBs detection was 76.8% among participants with HIV and 79.8% among participants without HIV.
Concordant results for anti-HBs in serum and dried blood spot samples had high mean CD8 cell counts, HIV viral load, and optical density values of anti-HBs.
Anti-HBs titers were higher in serum (401.98±375.43) compared with dried blood spot samples (157.37±124.24) among participants who were not infected with HIV (P =.006). This difference was not statistically significant among participants infected with HIV (P =.590).
The researchers were able to detect anti-HBs in dried blood spots as low as 17.4 IU/mL and 27.3 IU/mL among participants with HIV and participants without HIV, respectively.
“The present study demonstrates a similar sensitivity of anti-HBs testing in [dried blood spots ] from HIV-negative and HIV-positive subjects (79.8% and 76.8%), indicating the utility of the [dried blood spots] in increasing access to the screening of [hepatitis B]-susceptible (anti-HBs negative) individuals [who] could be targeted for [hepatitis B] vaccination,” the researchers wrote.
Flores GL, Cruz HM, Miguel JC, et a. Assessing hepatitis B immunity using dried blood spot samples from HIV+ individuals [published online August 7, 2018]. J Med Virol. doi:10.1002/jmv.25275