Serious bacterial infections in febrile young children : lack of value of biomarkers

Abstract

BACKGROUND : Serious infections in children are difficult to determine from symptoms and signs alone. Fever is both a marker of insignificant viral infection, as well as more serious bacterial sepsis. Therefore, seeking markers of invasive disease, as well as culture positivity for organisms, has been a goal of paediatricians for many years. In addition, the avoidance of unnecessary antibiotics is important in this time of emerging multiresistant micro-organisms. OBJECTIVE : To ascertain whether acute-phase reactant tests predict positive culture results. METHODS : A prospective, cross-sectional study over a 1-year period included all documented febrile children under the age of 5 years (with an axillary temperature ≥38°C) who presented to Steve Biko Academic Hospital, Pretoria, with signs and symptoms of pneumonia, meningitis and/or generalised sepsis. Every child had clinical signs, chest radiograph findings, urine culture, blood testing (full blood count, C-reactive protein, procalcitonin) and blood culture results recorded. RESULTS : A total of 63 patients were enrolled, all of whom had an axillary temperature ≥38°C. C-reactive protein, procalcitonin and white cell count did not predict the presence of positive blood culture or cerebrospinal fluid culture results, nor infiltrates on chest radiographs. No statistically significant correlations were found between the duration of hospital stay and the degree of fever (p=0.123), white cell count (p=0.611), C-reactive protein (p=0.863) or procalcitonin (p=0.392). CONCLUSION : Biomarkers do not seem to predict severity of infection, source of infection, or duration of hospitalisation in children presenting to hospital with fever. The sample size is however too small to definitively confirm this viewpoint. This study suggests that clinical suspicion of serious infection and appropriate action are as valuable as extensive testing.