Clinical and laboratory factors associated with platelet transfusion refractoriness: a case–control study

Abstract

In recent years clinical factors have largely surpassed alloimmunization as the predominant cause of platelet refractoriness. This makes it necessary to properly identify and weigh the non-immune factors that have a major impact of refractoriness. A case-control study is suitable for such an analysis, and to our knowledge has not previously been performed to assess this issue. Fifty-two refractory patients were compared with 52 control patients who were transfused at the same time. Only one transfusion event was analysed per patient. Clinical and laboratory data were recorded at the time of selected transfusion, and their association with refractoriness was investigated by the contingency table method and the Cox stepwise logistic regression. There were 16 (31%) patients with HLA antibodies in the index group and only one in the control group. The corrected count increment in the group of patients refractory due to HLA antibodies was significantly lower than that in non-alloimmunized refractory patients [median (range): 48.5 (-3560, 4614) and 4058 (-4417, 6886), respectively; U = 493, P < 0.0001]. In the multivariate analysis, factors associated with refractoriness were the presence of HLA antibodies (odds ratio (OR) 50.7; 95% CI 5.5-463); fever (odds ratio 7.2; 95% CI 2.5-21) and BMT because of chronic myeloid leukaemia (odds ratio 7.3; 95% CI 1.8-30). The latter two were the only factors that remained independently associated with refractoriness after excluding alloimmunized patients and their controls. We conclude that HLA antibodies are strongly associated with platelet transfusion refractoriness, but account for less than a third of these patients. Fever and BMT because of chronic myeloid leukaemia were the only non-immune factors independently associated with refractoriness.

Factors influencing post-transfusional platelet increment in pediatric patients given hematopoietic stem cell transplantation

“…This conclusion confirms previous data obtained in patient populations comprising transplanted and not-transplanted subjects. 9,24 However, different results were observed in the HSCT setting by Ishida et al, 4 who reported that antibodies to HLA-antigens had a relatively insignificant impact on 16-h CCI, while platelet-specific antibodies enhanced post-transfusion platelet efficacy. Since it is not possible to conciliate such opposite results, we are compelled to conclude that some confounding factor was unrecognized in one or other of the case series.…”

“…In order to gain further information in this field, we performed a prospective study, evaluating a number of clinical and immune factors which potentially affect or have been previously shown to affect the efficacy of platelet transfusion, 4,5,[8][9][10][11][12][13] in a series of 87 consecutive children who received 598 platelet transfusions after allogeneic HSCT carried out in a single institution.…”

Guías para la transfusión de sangre y sus componentes

“…Durante mucho tiempo se han usado las transfusiones de plaquetas con fines profilácticos, para mantener el recuento de plaquetas por encima del nivel que se considera seguro (15,17). Sin embargo, y a pesar de su amplio uso, muchos estudios no han podido demostrar la eficacia de su administración profiláctica (5, 16).…”

“…Se dice que un 20 a 60% de los pacientes no alcanzan los niveles deseados después de la transfusión y se consideran refractarios a la misma (17), fenómeno que se presenta como una complicación de su uso repetido (5). Sus causas incluyen la aloinmunización relacionada con antígenos plaquetarios y del sistema HLA, así como la autoinmunidad relacionada con otros antígenos, como ocurre en la púrpura trombocitopénica idiopática; en la refractariedad también se han implicado causas no inmunitarias, como la esplenomegalia, algunos medicamentos o la destrucción acelerada (4).…”

“…Sus causas incluyen la aloinmunización relacionada con antígenos plaquetarios y del sistema HLA, así como la autoinmunidad relacionada con otros antígenos, como ocurre en la púrpura trombocitopénica idiopática; en la refractariedad también se han implicado causas no inmunitarias, como la esplenomegalia, algunos medicamentos o la destrucción acelerada (4). Los anticuerpos del sistema HLA constituyen el principal indicador de refractariedad a la transfusión de plaquetas (17). El riesgo de transmisión de enfermedades es el mismo que con los componentes de GR, pero el riesgo de contaminación bacteriana es mayor debido a la temperatura de conservación de este componente (15).…”