Seed C R, Yang H, Lee J F
Australian Red Cross Blood Service, Perth, WA, Australia.
Australian Red Cross Blood Service, Sydney, NSW, Australia.
Vox Sang. 2017 Jul;112(5):473-476. doi: 10.1111/vox.12516. Epub 2017 Mar 31.
HIV pre-exposure prophylaxis (PrEP) is the use of one or more antiretroviral medications (in combination) to prevent HIV infection. The most commonly used PrEP medication (Truvada , Gilead Sciences, Inc.) acts by inhibiting HIV-1 reverse transcriptase. If someone who is using PrEP unknowingly becomes HIV infected (termed 'PrEP breakthrough infection'), there may be suppressed viral replication resulting in a virus level undetectable by the most sensitive HIV NAT. Failure to seroconvert and seroreversion (loss of previously detectable HIV antibodies) have also both been observed with 2nd, 3rd and 4th generation screening immunoassays, as well as Western blot assays. If such a person was tested in the course of donating blood, the results may therefore be difficult to interpret. The index of suspicion for possible PrEP 'interference' should be highest in the context of concomitant low-level positive or 'greyzone' reactivity on HIV NAT and serological tests, which is an unusual pattern in acutely HIV-infected blood donors. Another possibility is detectable HIV RNA with negative HIV serology (i.e. a potential 'NAT yield' case) but without subsequent HIV seroconversion (or disappearance of HIV RNA). Excluding antiretroviral therapy or PrEP use by the donor in such circumstances would be important. The current rarity of PrEP breakthrough infection indicates that any potential safety risk is likely very small. However, considering the increasing use of PrEP we feel it is prudent for those interpreting HIV donor screening test results to consider the potential for PrEP interference.
HIV暴露前预防（PrEP）是指使用一种或多种抗逆转录病毒药物（联合使用）来预防HIV感染。最常用的PrEP药物（舒发泰，吉利德科学公司）通过抑制HIV-1逆转录酶发挥作用。如果正在使用PrEP的人在不知情的情况下感染了HIV（称为“PrEP突破性感染”），可能会出现病毒复制受到抑制，导致最灵敏的HIV核酸检测无法检测到病毒水平。在第二代、第三代和第四代筛查免疫测定以及蛋白质印迹测定中，也都观察到了血清转换失败和血清逆转（先前可检测到的HIV抗体消失）的情况。因此，如果这样的人在献血过程中接受检测，结果可能难以解释。在HIV核酸检测和血清学检测同时出现低水平阳性或“灰区”反应性的情况下，对可能的PrEP“干扰”的怀疑指数应该最高，这在急性HIV感染的献血者中是一种不寻常的模式。另一种可能性是HIV血清学检测呈阴性但可检测到HIV RNA（即潜在的“核酸检测阳性”病例），但随后没有出现HIV血清转换（或HIV RNA消失）。在这种情况下，排除献血者使用抗逆转录病毒疗法或PrEP非常重要。目前PrEP突破性感染的罕见情况表明，任何潜在的安全风险可能都非常小。然而，考虑到PrEP的使用越来越多，我们认为对于解读HIV献血者筛查检测结果的人员来说，考虑PrEP干扰的可能性是谨慎的做法。
