Reference ranges for neuroprotein S-100B: from infants to adolescents

Background: Diagnosis and treatment of mild traumatic brain injuries in children are especially problematic. At present, computed tomography (CT) is the standard method to identify if patients with intracranial lesions require inpatient monitoring. CT, however, involves exposure to high doses of X-rays, which should be avoided if possible. In adults, the serum level of neuroprotein S-100B has already been proven to be effective for the selection of patients requiring CT. The aim of the present study was to determine reference ranges for serum S-100B in a large number of healthy children. Methods: All patients younger than 18 years with no recent history of head injuries presenting for routine operations were included in the study. Results: A total of 394 patients were evaluated. In children from 3 to 18 years an upper reference level of 0.16 mu g/ L was determined. There was a strong inverse relation between age and S-100B in patients younger than 3 years. As the values in this age group were scattered and the number of cases limited (n = 65), no reference range could be calculated. Conclusions: This study provides S-100B reference ranges for pediatric patients based on the largest group of healthy pediatric patients yet analyzed. Clin Chem Lab Med 2008; 46: 1296-9.