Hanson Josh, Phu Nguyen Hoan, Hasan Mahtab Uddin, Charunwatthana Prakaykaew, Plewes Katherine, Maude Richard J, Prapansilp Panote, Kingston Hugh W F, Mishra Saroj K, Mohanty Sanjib, Price Ric N, Faiz M Abul, Dondorp Arjen M, White Nicholas J, Hien Tran Tinh, Day Nicholas P J
Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia.
BMC Med. 2015 Apr 24;13:97. doi: 10.1186/s12916-015-0324-5.
Thrombocytopenia is a common finding in adults with severe falciparum malaria, but its clinical and prognostic utility is incompletely defined.
Clinical and laboratory data from 647 adults with severe falciparum malaria were analysed retrospectively to determine the relationship between a patient's platelet count on admission to hospital and their subsequent clinical course.
On admission, 614 patients (94.9%) were thrombocytopenic (platelet count <150 × 10(9)/L) and 328 (50.7%) had a platelet count <50 × 10(9)/L. The admission platelet count was inversely correlated with parasite biomass (estimated from plasma PfHRP2 concentrations, rs = -0.28, P = 0.003), the degree of microvascular sequestration (measured with orthogonal polarizing spectral imaging, rs = -0.31, P = 0.001) and disease severity (the number of World Health Organization severity criteria satisfied by the patient, rs = -0.21, P <0.001). Platelet counts were lower on admission in the patients who died (median: 30 (interquartile range 22 to 52) × 10(9)/L versus 50 (34 to 78) × 10(9)/L in survivors; P <0.001), but did not predict outcome independently from other established laboratory and clinical prognostic indices. The 39 patients (6%) with profound thrombocytopenia (platelet count <20 × 10(9)/L) were more likely to die (odds ratio: 5.00, 95% confidence interval: 2.56 to 9.75) than patients with higher platelet counts, but these high-risk patients could be identified more rapidly with simple bedside clinical assessment. The admission platelet count did not reliably identify the 50 patients (7.7%) with major bleeding during the study.
Thrombocytopenia is a marker of disease severity in adults with falciparum malaria, but has limited utility in prognostication, triage and management.
血小板减少症在患有严重恶性疟原虫疟疾的成年人中很常见，但其临床和预后价值尚未完全明确。
对647例患有严重恶性疟原虫疟疾的成年人的临床和实验室数据进行回顾性分析，以确定患者入院时的血小板计数与其随后临床病程之间的关系。
入院时，614例患者（94.9%）存在血小板减少症（血小板计数<150×10⁹/L），328例（50.7%）患者的血小板计数<50×10⁹/L。入院时的血小板计数与疟原虫数量（根据血浆PfHRP2浓度估算，rs=-0.28，P=0.003）、微血管滞留程度（用正交偏振光谱成像测量，rs=-0.31，P=0.001）和疾病严重程度（患者满足世界卫生组织严重程度标准的数量，rs=-0.21，P<0.001）呈负相关。死亡患者入院时的血小板计数较低（中位数：30（四分位间距22至52）×10⁹/L，而存活者为50（34至78）×10⁹/L；P<0.001），但与其他既定的实验室和临床预后指标相比，其并不能独立预测预后。39例（6%）患有严重血小板减少症（血小板计数<20×10⁹/L）的患者比血小板计数较高的患者死亡可能性更大（比值比：5.00，95%置信区间：2.56至9.75）但通过简单的床边临床评估可以更快地识别出这些高危患者。入院时的血小板计数并不能可靠地识别出研究期间发生大出血的50例（7.7%）患者。
血小板减少症是成年恶性疟原虫疟疾患者疾病严重程度的一个指标，但在预后评估、分诊和管理中的作用有限。
