Rogerson Stephen J, Mkundika Patrick, Kanjala Maxwell K
Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, University of Malawi, Blantyre, Malawi.
J Clin Microbiol. 2003 Apr;41(4):1370-4. doi: 10.1128/JCM.41.4.1370-1374.2003.
We compared peripheral and placental blood films (made by different techniques) with placental histology for diagnosis of Plasmodium falciparum malaria in pregnancy. Samples from 464 women were examined, of whom 124 (26.7%) had active P. falciparum infection and 148 (31.9%) had past infection. Placental histology was more sensitive (91%) than peripheral blood film (47%) or placental blood film (63%) examination and also detected past infection. Few women had microscopically detectable infection without a positive histology. Infection detected by histology only and past infection were both associated with significantly lower infant birth weight and with lower hemoglobin concentrations compared to the results for uninfected women. Thick blood films were prepared with blood obtained by placental incision or scraping of the incision margin (263 samples) or by washing of placental tissue (235 samples). Each gave similar sensitivities (76 to 78%), specificities (98 to 99%), positive predictive values (92 to 98%), and negative predictive values (93 to 94%); but the median levels of parasitemia were lower for incision samples (840 parasites/ micro l) than scrapings (2,295 parasites/ micro l) (P = 0.02). Placental histology is the most sensitive method for the diagnosis of malaria in pregnancy. Methods for preparation of placental films may affect the density, but not the prevalence, of P. falciparum infection detected.
我们比较了用于诊断妊娠期恶性疟原虫疟疾的外周血涂片和胎盘血涂片（采用不同技术制作）与胎盘组织学检查结果。对464名女性的样本进行了检测，其中124名（26.7%）患有活动性恶性疟原虫感染，148名（31.9%）曾有过感染。胎盘组织学检查比外周血涂片（47%）或胎盘血涂片（63%）检查更敏感（91%），并且还能检测出既往感染。很少有女性在组织学检查为阴性时镜检可检测到感染。与未感染女性的结果相比，仅通过组织学检查检测到的感染和既往感染均与婴儿出生体重显著降低以及血红蛋白浓度较低有关。厚血涂片是用通过胎盘切口或刮取切口边缘获得的血液（263份样本）或通过冲洗胎盘组织获得的血液（235份样本）制备的。每种方法的敏感性（76%至78%）、特异性（98%至99%）、阳性预测值（92%至98%）和阴性预测值（93%至94%）相似；但切口样本的疟原虫血症中位数水平（840个寄生虫/微升）低于刮取样本（2295个寄生虫/微升）（P = 0.02）。胎盘组织学检查是诊断妊娠期疟疾最敏感的方法。胎盘涂片的制备方法可能会影响检测到的恶性疟原虫感染的密度，但不会影响其患病率。
