Daneshvar Cyrus, Davis Timothy M E, Cox-Singh Janet, Rafa'ee Mohammad Zakri, Zakaria Siti Khatijah, Divis Paul C S, Singh Balbir
Malaria Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak, Malaysia.
Clin Infect Dis. 2009 Sep 15;49(6):852-60. doi: 10.1086/605439.
Plasmodium knowlesi is increasingly recognized as a cause of human malaria in Southeast Asia but there are no detailed prospective clinical studies of naturally acquired infections.
In a systematic study of the presentation and course of patients with acute P. knowlesi infection, clinical and laboratory data were collected from previously untreated, nonpregnant adults admitted to the hospital with polymerase chain reaction-confirmed acute malaria at Kapit Hospital (Sarawak, Malaysia) from July 2006 through February 2008.
Of 152 patients recruited, 107 (70%) had P. knowlesi infection, 24 (16%) had Plasmodium falciparum infection, and 21 (14%) had Plasmodium vivax. Patients with P. knowlesi infection presented with a nonspecific febrile illness, had a baseline median parasitemia value at hospital admission of 1387 parasites/microL (interquartile range, 6-222,570 parasites/microL), and all were thrombocytopenic at hospital admission or on the following day. Most (93.5%) of the patients with P. knowlesi infection had uncomplicated malaria that responded to chloroquine and primaquine treatment. Based on World Health Organization criteria for falciparum malaria, 7 patients with P. knowlesi infection (6.5%) had severe infections at hospital admission. The most frequent complication was respiratory distress, which was present at hospital admission in 4 patients and developed after admission in an additional 3 patients. P. knowlesi parasitemia at hospital admission was an independent determinant of respiratory distress, as were serum creatinine level, serum bilirubin, and platelet count at admission (p < .002 for each). Two patients with knowlesi malaria died, representing a case fatality rate of 1.8% (95% confidence interval, 0.2%-6.6%).
Knowlesi malaria causes a wide spectrum of disease. Most cases are uncomplicated and respond promptly to treatment, but approximately 1 in 10 patients develop potentially fatal complications.
诺氏疟原虫日益被认为是东南亚地区人类疟疾的病因，但尚无关于自然感染的详细前瞻性临床研究。
在一项对急性诺氏疟原虫感染患者的临床表现及病程的系统性研究中，收集了2006年7月至2008年2月期间在马来西亚砂拉越州卡皮特医院因聚合酶链反应确诊为急性疟疾而入院的既往未治疗、非妊娠成年患者的临床和实验室数据。
在招募的152例患者中，107例（70%）感染诺氏疟原虫，24例（16%）感染恶性疟原虫，21例（14%）感染间日疟原虫。诺氏疟原虫感染患者表现为非特异性发热性疾病，入院时基线疟原虫血症中位数为1387个寄生虫/微升（四分位间距，6 - 222,570个寄生虫/微升），且所有患者在入院时或次日均有血小板减少。大多数（93.5%）诺氏疟原虫感染患者为无并发症的疟疾，对氯喹和伯氨喹治疗有反应。根据世界卫生组织的恶性疟标准，7例诺氏疟原虫感染患者（6.5%）入院时患有严重感染。最常见的并发症是呼吸窘迫，入院时4例患者出现，入院后又有3例患者出现。入院时诺氏疟原虫血症是呼吸窘迫以及入院时血清肌酐水平、血清胆红素和血小板计数的独立决定因素（每项p < 0.002）。2例诺氏疟患者死亡，病死率为1.8%（95%置信区间，0.2% - 6.6%）。
诺氏疟可导致多种疾病。大多数病例无并发症且对治疗反应迅速，但约十分之一的患者会出现潜在致命并发症。
