Screening and Test Evaluation Program, School of Public Health, The University of Sydney, Sydney, Australia Centre for Kidney Research, The Children's Hospital at Westmead, Sydney, Australia.
Screening and Test Evaluation Program, School of Public Health, The University of Sydney, Sydney, Australia School of Public Health and Community Medicine, The University of New South Wales, Sydney, Australia.
Postgrad Med J. 2015 Mar;91(1073):493-9. doi: 10.1136/postgradmedj-2013-304754rep.
The leukocyte count is frequently used to evaluate suspected bacterial infections but estimates of its test performance vary considerably. We evaluated its accuracy for the detection of serious bacterial infections in febrile children.
Prospective cohort study.
Paediatric emergency department.
Febrile 0-5-year-olds who had a leukocyte count on presentation.
Accuracy of total white blood cell and absolute neutrophil counts for the detection of urinary tract infection, bacteraemia, pneumonia and a combined ('any serious bacterial infection') category. Logistic regression models were fitted for each outcome. Reference standards were microbiological/radiological tests and clinical follow-up.
Serious bacterial infections were present in 714 (18.3%) of 3893 illness episodes. The area under the receiver operating characteristic curve for 'any serious bacterial infection' was 0.653 (95% CI 0.630 to 0.676) for the total white blood cell count and 0.638 (95% CI 0.615 to 0.662) for absolute neutrophil count. A white blood cell count threshold >15×10(9)/L had a sensitivity of 47% (95% CI 43% to 50%), specificity 76% (95% CI 74% to 77%), positive likelihood ratio 1.93 (95% CI 1.75 to 2.13) and negative likelihood ratio 0.70 (95% CI 0.65 to 0.75). An absolute neutrophil count threshold >10×10(9)/L had a sensitivity of 41% (95% CI 38% to 45%), specificity 78% (95% CI 76% to 79%), positive likelihood ratio 1.87 (95% CI 1.68 to 2.09) and negative likelihood ratio 0.75 (95% CI 0.71 to 0.80).
The total white blood cell count and absolute neutrophil count are not sufficiently accurate triage tests for febrile children with suspected serious bacterial infection.
白细胞计数常用于评估疑似细菌感染，但对其检测性能的估计差异很大。我们评估了其在发热儿童中检测严重细菌感染的准确性。
前瞻性队列研究。
儿科急诊室。
就诊时有白细胞计数的发热 0-5 岁儿童。
总白细胞计数和绝对中性粒细胞计数对尿路感染、菌血症、肺炎和综合（“任何严重细菌感染”）类别的检测准确性。为每个结果拟合了逻辑回归模型。参考标准是微生物学/放射学检查和临床随访。
在 3893 个疾病发作中，有 714 个（18.3%）存在严重细菌感染。总白细胞计数对“任何严重细菌感染”的受试者工作特征曲线下面积为 0.653（95%CI 0.630 至 0.676），绝对中性粒细胞计数为 0.638（95%CI 0.615 至 0.662）。白细胞计数阈值>15×10(9)/L 的敏感性为 47%（95%CI 43%至 50%），特异性为 76%（95%CI 74%至 77%），阳性似然比为 1.93（95%CI 1.75 至 2.13），阴性似然比为 0.70（95%CI 0.65 至 0.75）。绝对中性粒细胞计数阈值>10×10(9)/L 的敏感性为 41%（95%CI 38%至 45%），特异性为 78%（95%CI 76%至 79%），阳性似然比为 1.87（95%CI 1.68 至 2.09），阴性似然比为 0.75（95%CI 0.71 至 0.80）。
白细胞计数和绝对中性粒细胞计数对于疑似严重细菌感染的发热儿童不是足够准确的分诊试验。
