Selecting girls with precocious puberty for brain imaging: Validation of European evidence-based diagnosis rule

Objectives To test the sensitivities of recently published American recommendations predicting occult intracranial lesion (OICL) in girls with central precocious puberty (CPP), and to validate a previously derived diagnosis rule predicting OICL based on age at puberty onset and estradiol (E2) level. Study design A retrospective, multicenter, hospital-based, cohort study was performed, including all girls with CPP seen in 7 centers in 6 European countries during given periods. American recommendations and the previously derived diagnosis rule were tested. Results Girls with CPP (n = 443), including 35 with OICL, were recruited. American recommendations did not identify all OICL. Previously identified independent risk factors for OICL were confirmed: age <6 years (adjusted odds ratio 20.5; 95% CI, 8.1-52.1) and E2 >45th percentile (3.0; 95% CI, 1.3-7.1). The previously derived diagnosis rule had 100% sensitivity (95% CI, 90-100): all girls with OICL had either an age <6 years or an E2 level >45th percentile. The specificity was 39% (95% CI, 34-44). Conclusions American recommendations do not seem safe to select European girls with CPP who require brain imaging. In settings where systematic brain imaging is not possible, the proposed diagnosis rule could safely help to avoid more than one third of unnecessary brain imaging.