Shrivastava Vikas, Ahmad Sohaib, Mittal Garima, Gupta Vibha, Shirazi Nadia, Kalra Varun
Department of Pathology, Himalayan Institute of Medical Sciences, Dehradun, India.
Department of Medicine, Himalayan Institute of Medical Sciences, Dehradun, India.
Trans R Soc Trop Med Hyg. 2017 Dec 1;111(12):546-554. doi: 10.1093/trstmh/try012.
In this follow-up study, we aimed to establish the cut-off values of the volume, conductivity and scatter (VCS) parameters of leucocytes that significantly differ in dengue fever, malaria, scrub typhus and enteric fever, as described in our pilot study.
A prospective observational case-control study was undertaken on patients with an established diagnosis of acute malaria (n=476), dengue fever (n=927), scrub typhus (n=425), bacterial sepsis (n=1598) or enteric fever (n=885) and the haematological and VCS data obtained by the Coulter LH 750 analyser were compared with controls.
Malaria significantly altered the platelet count and plateletcrit. The cut-offs for the monocyte volume, lymphocyte volume, neutrophil volume, neutrophil volume distribution width, lymphocyte volume distribution width, monocyte volume distribution width and neutrophil conductivity distribution width had 90% negative predictive values (NPVs) for malaria. Except for the proportion of monocytes, lymphocyte scatter distribution width and platelet distribution width, a >70% positive (PPV) and negative predictive value (NPV) for dengue was noted in all the haematological and VCS parameters analysed. While the cut-offs determined in scrub typhus had a good (>80%) PPV and NPV, a significant difference was seen in neutrophil, monocyte and lymphocyte conductivities, but with low sensitivity, specificity, PPV and NPV in enteric fever.
Aetiology-specific changes occur both in numbers as well as in VCS properties in acute fevers. Formulae and/or algorithms need to be utilized to realize the full potential of the VCS technology.
在这项随访研究中，我们旨在确定白细胞体积、电导率和散射（VCS）参数的临界值，这些参数在登革热、疟疾、恙虫病和伤寒中存在显著差异，正如我们的初步研究所描述的那样。
对确诊为急性疟疾（n = 476）、登革热（n = 927）、恙虫病（n = 425）、细菌性败血症（n = 1598）或伤寒（n = 885）的患者进行了一项前瞻性观察性病例对照研究，并将通过库尔特LH 750分析仪获得的血液学和VCS数据与对照组进行比较。
疟疾显著改变了血小板计数和血小板压积。单核细胞体积、淋巴细胞体积、中性粒细胞体积、中性粒细胞体积分布宽度、淋巴细胞体积分布宽度、单核细胞体积分布宽度和中性粒细胞电导率分布宽度的临界值对疟疾具有90%的阴性预测值（NPV）。除单核细胞比例、淋巴细胞散射分布宽度和血小板分布宽度外，在所有分析的血液学和VCS参数中，登革热的阳性预测值（PPV）和阴性预测值（NPV）均>70%。虽然恙虫病中确定的临界值具有良好的（>80%）PPV和NPV，但在伤寒中，中性粒细胞、单核细胞和淋巴细胞的电导率存在显著差异，但其敏感性、特异性、PPV和NPV较低。
急性发热时，病因特异性变化不仅发生在数量上，也发生在VCS特性上。需要利用公式和/或算法来充分发挥VCS技术的潜力。
