Ngasala Billy, Mubi Marycelina, Warsame Marian, Petzold Max G, Massele Amos Y, Gustafsson Lars L, Tomson Goran, Premji Zul, Bjorkman Anders
Infectious Diseases Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.
Malar J. 2008 Oct 2;7:199. doi: 10.1186/1475-2875-7-199.
Prescribing antimalarial medicines based on parasite confirmed diagnosis of malaria is critical to rational drug use and optimal outcome of febrile illness. The impact of microscopy-based versus clinical-based diagnosis of childhood malaria was assessed at primary health care (PHC) facilities using a cluster randomized controlled training intervention trial.
Sixteen PHC facilities in rural Tanzania were randomly allocated to training of health staff in clinical algorithm plus microscopy (Arm-I, n = 5) or clinical algorithm only (Arm-II, n = 5) or no training (Arm-III, n = 6). Febrile under-five children presenting at these facilities were assessed, treated and scheduled for follow up visit after 7 days. Blood smears on day 0 were only done in Arm-I but on Day 7 in all arms. Primary outcome was antimalarial drug prescription. Other outcomes included antibiotic prescription and health outcome. Multilevel regression models were applied with PHC as level of clustering to compare outcomes in the three study arms.
A total of 973, 1,058 and 1,100 children were enrolled in arms I, II and III, respectively, during the study period. Antimalarial prescriptions were significantly reduced in Arm-I (61.3%) compared to Arms-II (95.3%) and III (99.5%) (both P < 0.001), whereas antibiotic prescriptions did not vary significantly between the arms (49.9%, 54.8% and 34.2%, respectively). In Arm-I, 99.1% of children with positive blood smear readings received antimalarial prescriptions and so did 11.3% of children with negative readings. Those with positive readings were less likely to be prescribed antibiotics than those with negative (relative risk = 0.66, 95% confidence interval: 0.55, 0.72). On day 7 follow-up, more children reported symptoms in Arm-I compared to Arm-III, but fewer children had malaria parasitaemia (p = 0.049). The overall sensitivity of microscopy reading at PHC compared to reference level was 74.5% and the specificity was 59.0% but both varied widely between PHCs.
Microscopy based diagnosis of malaria at PHC facilities reduces prescription of antimalarial drugs, and appears to improve appropriate management of non-malaria fevers, but major variation in accuracy of the microscopy readings was found. Lack of qualified laboratory technicians at PHC facilities and the relatively short training period may have contributed to the shortcomings.
This study is registered at Clinicaltrials.gov with the identifier NCT00687895.
基于寄生虫确诊的疟疾来开具抗疟药物对于合理用药和发热性疾病的最佳治疗效果至关重要。在初级卫生保健(PHC)机构中,采用整群随机对照培训干预试验评估了基于显微镜检查与基于临床诊断的儿童疟疾诊断方法的影响。
坦桑尼亚农村地区的16个初级卫生保健机构被随机分配,分别接受临床算法加显微镜检查培训(第一组,n = 5)、仅接受临床算法培训(第二组,n = 5)或不接受培训(第三组,n = 6)。在这些机构就诊的5岁以下发热儿童接受评估、治疗,并安排在7天后进行随访。第0天的血涂片仅在第一组进行,但所有组在第7天均进行。主要结局是抗疟药物处方。其他结局包括抗生素处方和健康结局。应用多水平回归模型,以初级卫生保健机构为聚类水平,比较三个研究组的结局。
在研究期间,第一组、第二组和第三组分别共有973名、1058名和1100名儿童入组。与第二组(95.3%)和第三组(99.5%)相比,第一组的抗疟药物处方显著减少(61.3%)(P均<0.001),而各组之间的抗生素处方无显著差异(分别为49.9%、54.8%和34.2%)。在第一组中,血涂片读数阳性的儿童中有99.1%接受了抗疟药物处方,读数阴性的儿童中也有11.3%接受了抗疟药物处方。读数阳性的儿童比读数阴性的儿童接受抗生素处方的可能性更小(相对风险 = 0.66,95%置信区间:0.55,0.72)。在第7天随访时,与第三组相比,第一组报告有症状的儿童更多,但患疟疾寄生虫血症的儿童更少(P = 0.049)。与参考水平相比,初级卫生保健机构显微镜检查读数的总体敏感性为74.5%,特异性为59.0%,但各初级卫生保健机构之间差异很大。
初级卫生保健机构基于显微镜检查的疟疾诊断减少了抗疟药物的处方,似乎改善了对非疟疾发热的合理管理,但发现显微镜检查读数的准确性存在很大差异。初级卫生保健机构缺乏合格的实验室技术人员以及培训期相对较短可能是造成这些不足的原因。
本研究已在Clinicaltrials.gov注册,标识符为NCT00687895。