BACKGROUND Thrombocytopenia in malaria involves platelet destruction and consumption; however, the cellular response underlying this phenomenon has still not been elucidated. OBJECTIVE To find associations between platelet indices and unbalanced Th1/Th2/Th17 cytokines as a response to thrombocytopenia in Plasmodium vivax infected (Pv-MAL) patients. METHODS Platelet counts and quantification of Th1/Th2/Th17 cytokine levels were compared in 77 patients with uncomplicated P. vivax malaria and 37 healthy donors from the same area (endemic control group - ENCG). FINDINGS Thrombocytopenia was the main manifestation in 55 patients, but was not associated with parasitaemia. The Pv-MAL patients showed increases in the mean platelet volume (MPV), which may be consistent with larger or megaplatelets. Contrary to the findings regarding the endemic control group, MPV and platelet distribution width (PDW) did not show an inverse correlation, due the increase in the heterogeneity of platelet width. In addition, the Pv-MAL patients presented increased IL-1β and reduced IL-12p70 and IL-2 serum concentrations. Furthermore, the reduction of these cytokines was associated with PDW values. MAIN CONCLUSIONS Our data demonstrate that an increase in MPV and the association between reductions of IL-2 and IL-12 and PDW values may be an immune response to thrombocytopenia in uncomplicated P. vivax malaria.

中文翻译：

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间日疟原虫疟疾的血小板减少症与血小板分布宽度增加和IL-2和IL-12减少有关。

背景技术疟疾中的血小板减少症涉及血小板的破坏和消耗。然而，尚未阐明这种现象的细胞反应。目的探讨间日疟原虫感染（Pv-MAL）患者血小板指数与不平衡的Th1 / Th2 / Th17细胞因子之间的关联，作为对血小板减少症的反应。方法比较了77例单纯性间日疟原虫疟疾患者和37例来自同一地区的健康捐献者（地方病对照组-ENCG）的血小板计数和Th1 / Th2 / Th17细胞因子水平的定量。结果血小板减少症是55例患者的主要表现，但与寄生虫血症无关。Pv-MAL患者显示平均血小板体积（MPV）增加，这可能与更大或更大的血小板一致。与地方病对照组的发现相反，由于血小板宽度异质性的增加，MPV与血小板分布宽度（PDW）没有显示出反相关关系。此外，Pv-MAL患者的IL-1β升高，IL-12p70和IL-2血清浓度降低。此外，这些细胞因子的减少与PDW值有关。主要结论我们的数据表明，MPV的升高以及IL-2和IL-12和PDW值的降低之间的关联可能是对单纯性间日疟原虫疟疾中血小板减少症的免疫反应。此外，这些细胞因子的减少与PDW值有关。主要结论我们的数据表明，MPV的升高以及IL-2和IL-12和PDW值的降低之间的关联可能是对单纯性间日疟原虫疟疾中血小板减少症的免疫反应。此外，这些细胞因子的减少与PDW值有关。主要结论我们的数据表明，MPV的升高以及IL-2和IL-12和PDW值的降低之间的关联可能是对单纯性间日疟原虫疟疾中血小板减少症的免疫反应。