RT Journal Article
SR Electronic
T1 Value of white cell count in predicting serious bacterial infection in febrile children under 5 years of age
JF Archives of Disease in Childhood
JO Arch Dis Child
FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health
SP 493
OP 499
DO 10.1136/archdischild-2013-304754
VO 99
IS 6
A1 Sukanya De
A1 Gabrielle J Williams
A1 Andrew Hayen
A1 Petra Macaskill
A1 Mary McCaskill
A1 David Isaacs
A1 Jonathan C Craig
YR 2014
UL http://adc.bmj.com/content/99/6/493.abstract
AB Objective 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. Design Prospective cohort study. Setting Paediatric emergency department. Patients Febrile 0–5-year-olds who had a leukocyte count on presentation. Outcome measures 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. Results 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 >15×109/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 >10×109/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). Conclusions The total white blood cell count and absolute neutrophil count are not sufficiently accurate triage tests for febrile children with suspected serious bacterial infection.