Page 287 - AIDSBK23C

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In addition, screening questions applied to potential donors are aimed at determination of
possible high-risk behaviors which exclude them as donors (sex with another man even once,
injection drug use, etc.) and symptoms of infection (generalized lymph node enlargement,
mucocutaneous lesions, weight loss, etc.). Blood collection facilities also employ a confidential
unit exclusion form which provides donors who are under duress to donate, but do not want to
resist or answer truthfully for fear of being detected with HIV infection, to designate their blood
as unsuitable for transfusion. Such donor self-deferral is effective in reducing the risk of HIV
transmission through transfusion of blood products.[1127] Autologous donations for elective
surgical procedures have been encouraged, but directed donations have been found to be no safer
than the routine blood supply.[109,1128]
In addition to donor screening, blood processing technology can provide safeguards for
transfusion therapy. Whole blood fractionation can include viral reduction treatments that
include viral inactivation steps in which mainly enveloped viruses are killed as well as viral
removal steps where mainly non-enveloped viruses are partitioned into specific fractions. As a
consequence, there have been no documented transmissions since the late 1980’s of HIV,
hepatitis B virus, and hepatitis C virus by blood products that have been subjected to such
inactivation treatments. This includes blood plasma and derivatives.[1129]
Liability problems for blood banks stem from the few blood products that have
transmitted HIV to recipients. In the U.S., courts in some jurisdictions have held that as long as
blood suppliers meet professional standards of practice they are immune from liability.
However, in other jurisdictions, blood suppliers have been found negligent despite meeting the
established standard of care for the time period in which transmission of HIV occurred, implying
that by maintaining liability there should be an incentive to adopt new precautionary measures to
increase the safety level of the blood supply. Blood banks have also been held accountable for
maintaining confidentiality of testing donors and for maintaining records of such testing. Many
jurisdictions also require mandatory reporting of HIV positive donors. Thus, potential donors
should be advised of the confidentiality protections as well as the circumstances under which test
results will be disclosed.[1130]
AIDS patients may require transfusion therapy for cytopenias resulting from progression
of their disease and from bone marrow suppression resulting from drug therapy for infections or
neoplasms associated with AIDS. Additionally, zidovudine (ZDV) chemotherapy against HIV
has as a side effect significant severe cytopenias in about 12% of patients who take this drug.
Blood products administered to AIDS patients have the potential for graft versus host reactions,
but there have been no significant studies to suggest that this occurs frequently. There is no
evidence that viral or cytokine activation occurs following blood transfusion in patients with
advanced HIV infection, and leukoreduction appears to have no clinical benefit.[1131].
Transplantation of human tissues and organs also carries the potential risk for HIV
transmission. Transplantation involving kidney, liver, heart, pancreas, bone, and skin have been
reported to be associated with this risk. Nucleic acid amplification testing may reduce the risk to
1 in 315,000 donors but a window period prior to seroconversion remains.[1132,1133]
Autologous transplants do not carry this risk, except potentially via administrative errors. In
addition, HIV transmission via artificial insemination from banked sperm has occurred. Human
milk also carries a potential risk.[1134,1135]
Screening of potential donors through assessment of risk factors and through testing for
HIV (enzyme immunoassay with Western blot confirmation) should be performed similar to that
for blood donation. In the case of cadaveric donors, a history must be obtained from available