Central nervous system imaging in girls with central precocious puberty: when is necessary?

ABSTRACT Objectives The determinants of an increased risk of an organic pathology underlying central precocious puberty (CPP) in girls remain contentious. The present study aimed to determine the clinical and hormonal findings that can be used to differentiate organic and idiopathic CPP in girls as a screening method so that only those considered likely to have organic CPP undergo cranial magnetic resonance imaging (MRI). Subjects and methods The medical records of 286 girls that received GnRH agonist (GnRHa) therapy for CPP were retrospectively evaluated. Chronological and bone age, height, pubertal stage, and basal/stimulated gonadotropin and estradiol (E2) levels, as well as cranial MRI findings at the time CPP was diagnosed were recorded. Clinical and hormonal parameters that can be used to differentiate between girls with organic and idiopathic CPP were identified using ROC curves. Results Organic CPP was noted in 6.3% of the participants. Puberty started before age 6 years in 88.9% of the girls with organic CPP. Mean E2 and peak luteinizing hormone (LH) levels were higher in the girls with organic CPP than in those with idiopathic CPP that were matched for pubertal stage, as follows: early stage puberty (Tanner 2 and 3): E2: 62.4 ± 19.8 pg/mL vs. 29.1 ± 9.5 pg/mL; peak LH: 16.8 ± 3.2 IU/L vs. 12.2 ± 3.7 IU/L; advanced stage puberty (Tanner 4): mean E2: 87.6 ± 3.4 pg/mL vs. 64.6 ± 21.2 pg/mL; peak LH: 20.8 ± 0.4 IU/L vs. 16.6 ± 5.8 IU/L (P < 0.001 for all). Thresholds for differentiating organic and idiopathic CPP in girls with early-stage puberty were 38.1 pg/mL for E2 (100% sensitivity and 80.4% specificity) and 13.6 IU/L for peak LH (100% sensitivity and 66.4% specificity). Conclusion Pubertal symptoms and signs generally begin before age 6 years and hormone levels are much higher than expected for pubertal stage in girls with organic CPP. Based on the present findings, cranial MRI is recommended for girls aged < 6 years, as the risk of diagnosing an organic pathology is highest in this age group. Hormone levels higher than expected for pubertal stage might be another indication for cranial MRI, regardless of patient age. Cranial MRI should be performed in girls with early-stage puberty, and an E2 level > 38 pg/mL and/or a peak LH level > 13.6 IU/L.

The role of the resistive index in Hashimoto's thyroiditis: a Sonographic pilot study in children

OBJECTIVE: The role of Doppler ultrasonography in the diagnosis of diffuse thyroid diseases is not well established. In particular, Doppler ultrasonography findings in children with Hashimoto's thyroiditis are very limited. We examined gray-scale and Doppler ultrasound findings in Hashimoto's thyroiditis in children in an attempt to understand the feasibility of future prospective controlled studies. MATERIALS AND METHODS: Twenty-one children with newly diagnosed Hashimoto's thyroiditis were recruited in the study. The patients were euthyroid or had subclinical hypothyroidism at the time of the ultrasonography examination. According to the color Doppler scale developed by Schulz et al., thyroid glands were classified into four patterns based on visual scoring and the mean resistive index (RI), which was calculated via measurements from both lobes, and these results were compared with gray-scale findings. RESULTS: The mean RI value, calculated as the mean of the RI values of both lobes obtained from each patient, was found to be 0.57 ± 0.05 (range 0.48-0.67) cm/sn. The distribution of thyroid classifications was as follows: Pattern 0, n = 7; Pattern I, n = 6; Pattern II, n = 4; and Pattern III ("thyroid inferno"), n = 4. The mean RI values in patients with normal or near-normal gray-scale findings (n = 10) and patients with more substantial gray-scale changes (n = 11) were not significantly different and were lower than the values in normal children previously presented in the literature. CONCLUSION: The results indicated that the RI may be more sensitive than other ultrasound parameters for the diagnosis of Hashimoto's thyroiditis.