Department of Internal Medicine, Harbour Hospital Rotterdam, Rotterdam, The Netherlands.
Malar J. 2013 Mar 18;12:101. doi: 10.1186/1475-2875-12-101.
Lymphocytopenia has frequently been described in patients with malaria, but studies on its association with disease severity have yielded conflicting results. The neutrophil/lymphocyte count ratio (NLCR) has been introduced as a parameter for systemic inflammation in critically ill patients and was found, together with lymphocytopenia, to be a better predictor of bacteraemia than routine parameters like C-reactive protein and total leukocyte count. In the present study, the predictive value of the NLCR and lymphocytopenia for severe disease was evaluated in patients with imported malaria.
All patients diagnosed with malaria at the Harbour Hospital between January 1st 1999 and January 1st 2012 with differential white cell counts determined within the first 24 hours after admission were included in this retrospective study. Severe malaria was defined according to the WHO criteria. The performance of the NLCR and lymphocytopenia as a marker of severe malarial disease was compared back-to-back with that of C-reactive protein as a reference biomarker.
A total of 440 patients (severe falciparum malaria n = 61, non-severe falciparum malaria n = 259, non-falciparum malaria n=120) were included in the study. Lymphocytopenia was present in 52% of all patients and the median NLCR of all patients was 3.2. Total lymphocyte counts and NLCR did not differ significantly between groups. A significant correlation of total leukocyte count and NLCR, but not lymphocyte count, with parasitaemia was found. ROC analysis revealed a good negative predictive value but a poor positive predictive value of both lymphocytopenia and NLCR and performance was inferior to that of C-reactive protein. After complete parasite clearance a significant rise in total leukocyte count and lymphocyte count and a significant decrease in NLCR was observed.
The NLCR was found to correlate with parasitaemia, but both lymphocytopenia and the NLCR were inferior to C-reactive protein as markers for severe disease in patients with imported malaria. The NLCR and lymphocytopenia are not useful as predictive markers for severe disease in imported malaria in the acute care setting.
淋巴细胞减少症在疟疾患者中经常被描述，但关于其与疾病严重程度的关系的研究结果却存在矛盾。中性粒细胞/淋巴细胞计数比值（NLCR）已被引入作为危重病患者全身炎症的参数，并且与淋巴细胞减少症一起，被发现比 C 反应蛋白和总白细胞计数等常规参数更好地预测菌血症。在本研究中，评估了 NLCR 和淋巴细胞减少症对输入性疟疾患者严重疾病的预测价值。
本回顾性研究纳入了 1999 年 1 月 1 日至 2012 年 1 月 1 日期间在海港医院诊断为疟疾的所有患者，且在入院后 24 小时内确定了白细胞分类计数。严重疟疾根据世界卫生组织标准定义。将 NLCR 和淋巴细胞减少症作为严重疟疾的标志物与 C 反应蛋白作为参考生物标志物进行了一对一的比较。
共纳入 440 例患者（严重恶性疟原虫疟疾 n = 61，非严重恶性疟原虫疟疾 n = 259，非恶性疟原虫疟疾 n = 120）。所有患者中有 52%存在淋巴细胞减少症，所有患者的 NLCR 中位数为 3.2。各组之间的总淋巴细胞计数和 NLCR 无显著差异。总白细胞计数和 NLCR 与寄生虫血症呈显著相关性，但淋巴细胞计数无相关性。ROC 分析显示，淋巴细胞减少症和 NLCR 的阴性预测值较好，但阳性预测值较差，且性能劣于 C 反应蛋白。完全清除寄生虫后，总白细胞计数和淋巴细胞计数显著升高，NLCR 显著下降。
NLCR 与寄生虫血症相关，但在输入性疟疾患者中，淋巴细胞减少症和 NLCR 均不如 C 反应蛋白作为严重疾病的标志物。NLCR 和淋巴细胞减少症在急性护理环境中对输入性疟疾严重疾病无预测价值。
