Unidentified bright objects on brain MRI in children as a diagnostic criterion for neurofibromatosis type 1

Background Lesions of the brain denominated as unidentified bright objects (UBOs), which are not included in the diagnostic criteria for neurofibromatosis type 1 (NF1) established by the National Institutes of Health (NIH), have been detected by MRI. Objective The purpose of this study was to investigate the possibility of including the presence of UBOs as a diagnostic criterion for NF1 in children. Materials and methods The study included 88 children between the ages of 2 and 18 years. The case group consisted of 40 children diagnosed with sporadic or familial NF1 according to the criteria established by the NIH. A control group consisted of 48 individuals referred for routine MRI of the brain for other complaints not related to NF1. Results UBOs were identified in 70% of the NF1 patients and in none of the control group. The sensitivity of the presence of UBOs for the diagnosis of NF1 was 70% (CI 53–83%), with a false-negative rate of 30% (CI 27–47%), a specificity of 100% (CI 86–100%) and a false-positive rate of 0% (CI 0–14%). Conclusion Faced with the difficulties in diagnosing NF1 in children and the high frequency and specificity of the presence UBOs identified by MRI in our series, we recommend the inclusion of the presence UBOs as a diagnostic criterion for NF1 in children.