In Platelet Refractory Patients with Acute Myelogenous Leukemia, Renal Dysfunction Correlates with Shortened Survival - Abstract
We retrospectively examined the impact of platelet
refractoriness on survival in acute myeloid leukemia (AML)
patients, an occurrence that may significantly impact even fit
older patients [1]. We compared platelet-refractory versus AMLcontrol patients and learned that among AML-platelet refractory
patients, renal dysfunction correlated with significantly shorter
survival.
Platelet transfusions are essential in patients receiving
myelosuppressive chemotherapy to minimize hemorrhage
incidence; however, transfusions may provoke alloimmunization
leading to refractoriness (inadequate post-transfusion count
increment). Indeed, 5-15% of patients receiving chronic platelet
transfusions become refractory [2].
Accepted quantitative definitions of platelet refractoriness
in AML include two concurrent 1-hour post transfusion count
increments of <11,000/uL or 18-24-hour post-transfusion count
increments of <2,000/uL [2,3].
Platelet refractoriness etiologies are divided into immune
and non-immune factors [3]. Non-immune factors prevail rather
than human leukocyte antigen (HLA)-antibody or rarely human
platelet antigen (HPA)-antibody immune factors [3]. Indeed, the
development of such alloantibodies does not always produce
immune-mediated platelet refractoriness. Immune-mediated
platelet refractory patients may be treated with positively or
negatively matching donor-recipient HLA antigens or crossmatching platelets. Positive donor-recipient HLA antigen
matching entails transfusing donor platelets with HLA types as
similar to the recipient’s as possible. Unfortunately, up to 60% of
such transfusions fail to increase the platelet count [4]. Negative
matching, or antigen avoidance, involves administration of
platelets from donors whose HLA antigens do not correspond
to high-level recipient HLA antibodies. Cross-matching selects
single-donor units non-reactive with recipient plasma and is
suitable for recipients with either anti-HLA or –HPA antibodies.
Positive and negative HLA-matched and cross match-compatible
platelets are equally effective [2].