Evaluation of the diagnostic performance of platelet-derived indices for the differential diagnosis of thrombocytopenia in pediatrics / Evaluación del rendimiento diagnóstico de los índices plaquetarios en el diagnóstico diferencial de las trombocitopenias en pediatría

ABSTRACT

Background. Platelet-derived indices have a well-established correlation with the differential diagnosis of thrombocytopenia in adult-based research. These indices include mean platelet volume, platelet distribution width, and platelet-large cell ratio. Objective. To determine the values of platelet-derived indices in a pediatric population with diagnoses of thrombocytopenia and their etiologic correlation. Materials and methods. Analytic observational diagnostic-test study. The population for this analytical study was pediatric patients between 6 months and 18 years of age who had thrombocytopenia (<100x10(9)/L). The study period was 18 months long. Results. Of 54 subjects, 18 (33.3%) were diagnosed with idiopathic thrombocytopenic purpura, and 36 (66.7%) were diagnosed with acute leukemia. Mean age was 7.4 years and 6.8 years for immune thrombocytopenic purpura and acute leukemia, respectively. Mean platelet distribution width values for immune thrombocytopenic purpura and acute leukemia were 15.08 fL and 10.73, respectively. Mean MPV for immune thrombocytopenic purpura and acute leukemia was 11.7 fL and 9.8 fL, respectively. Mean platelet-large cell ratio was 38.26% and 24.97% for idiopathic thrombocytopenic purpura and acute leukemia, respectively. Differences in these three distinct platelet indices between idiopathic thrombocytopenic purpura and acute leukemia were statistically significant (p=0.00). The area under the ROC curve for platelet-derived indices showed that they were adequate for defining the causes of thrombocytopenia. MPV and platelet-large cell ratio had an area under the curve of 0.89 and 0.88, respectively, while platelet size deviation width had an area under the curve of 0.903. Conclusions. Platelet-derived indices could be useful in the initial approach for the differential diagnosis of pediatric patients with thrombocytopenia.

RESUMEN

Antecedentes. Los índices plaquetarios tienen buena correlación con la etiología de la trombocitopenia en estudios realizados en adultos. Estos son volumen plaquetario medio, ancho de distribución plaquetaria y porcentaje de plaquetas grandes. Objetivo. Determinar las características de los índices plaquetarios en población pediátrica con trombocitopenia y su posible correlación etiológica. Materiales y métodos. Estudio de prueba diagnóstica observacional analítico. Realizado con pacientes entre 6 meses y 18 años ingresados en un período de 18 meses con trombocitopenia <100x10(9)/L. Resultados. 54 pacientes 18 (33,3%) con púrpura trombocitopénica inmune y 36 (66,7%) con leucemia aguda. Edad media para púrpura trombocitopénica inmune 7,4 años y 6,8 para leucemia aguda. Valores de ancho de distribución plaquetaria con media de 15,08 fL en púrpura trombocitopénica inmune y 10,73 para leucemia aguda. Media del volumen plaquetario medio para púrpura trombocitopénica inmune 11,7 fL y de 9,8 fL para leucemia aguda. Porcentaje de plaquetas grandes la media para púrpura trombocitopénica inmune 38,26% y 24,97% para leucemia aguda. Las diferencias de los tres índices para cada una de las enfermedades fueron estadísticamente significativas (p=0,00). Las curvas de Característica Operativa del Receptor de los índices plaquetarios fueron parámetros suficientes para distinguir las causas de trombocitopenia volumen plaquetario medio y porcentaje de plaquetas grandes con un área bajo la curva de 0,89 y 0,88 y ancho de distribución plaquetaria 0,903. Conclusiones. Los índices plaquetarios fueron útiles para el acercamiento inicial al diagnóstico diferencial de trombocitopenias en niños.