Dedicated sellar magnetic resonance imaging protocols without contrast enhancement in girls with central precocious puberty: prevalence of pathologic lesions and clinical correlation

ABSTRACT Objective: Contrast-enhanced brain magnetic resonance imaging (MRI) is routinely performed in children with central precocious puberty (CPP). We evaluated the value of a dedicated sellar MRI protocol without contrast enhancement in girls with CPP. Subjects and methods: This study included 261 girls diagnosed with CPP. We performed sellar MRI scanning without gadolinium enhancement of the hypothalamic-pituitary area (HPA) at the pituitary level, including additional T2-weighted imaging of whole-brain scans to check for other lesions. We evaluated the prevalence of intracranial lesions via this MR protocol. In addition,the correlation between the clinical parameters and morphology of the pituitary gland on the images was assessed. Results: Intracranial lesions were detected in 17 (6.5%) of the 261 girls. Of the 17 girls with abnormalities, 16 (94.1%) had findings in brain areas other than the HPA. The weight, height, Tanner stage of patients were significantly (p < 0.05) higher in the group with greater pituitary height. Patient weight and height, Tanner stage of breast development, and luteinizing hormone (LH) levels were significantly (p < 0.05) greater in those with a higher pituitary grade as determined on sellar MRI. Conclusion: A dedicated unenhanced sellar MRI protocol provides valuable information on brain lesions and pituitary morphology. We found a significantly low prevalence of brain lesions among girls with CPP. Analysis of the height or shape of the pituitary gland on sellar MRI revealed significant correlations with the weight, height, Tanner stage, and LH levels of the patients.

Pubertad precoz periférica / Peripheral precocious puberty

Introducción: El síndrome de Mc Cune-Albright (SMA) es una rara entidad asociada con la displasia fibrosa poliostótica, con la presencia de manchas de color café con leche y también con la hiperfunción endocrina. La alteración hormonal más frecuente es la pubertad precoz. El SMA se debe a mutaciones activadoras del gen GNAS1. Objetivo: Describir las características clínicas de una paciente con síndrome de Mc Cune-Albright con una pubertad precoz. Métodos: Se realizó una revisión de la historia clínica como fuente primaria y fueron incorporados todos los elementos clínicos, bioquímicos, imagenológicos y genéticos que conformaron la valoración integral de la paciente. Presentación de caso: Se presenta un caso poco frecuente de síndrome de Mc Cune-Albright en una niña de siete años de edad con mamas Tanner II-III, sangrado vaginal, vello axilar y pubiano escaso, manchas café con leche y lesiones óseas. Lleva tratamiento con tamoxifeno, lo que ha logrado mantener frenada la progresión del desarrollo puberal. Conclusiones: Aunque esta entidad es de carácter benigno y la prevalencia es extremadamente baja, el inicio puberal precoz y el compromiso de la talla final pueden producir impacto psicológico en la calidad de vida y en el desarrollo normal del individuo(AU)

Introduction: Mc Cune-Albright syndrome (SMA, by its acronym in Spanish) is a rare entity associated with polyostotic fibrous dysplasia, with the presence of brown spots with milk and also with endocrine hyperfunction. The most common hormonal alteration is precocious puberty. SMA is caused by GNAS1 gene´s activator mutations. Objective: Describe the clinical characteristics of a patient with Mc Cune-Albright syndrome with precocious puberty. Methods: A review of the medical history was carried out as a primary source and all the clinical, biochemical, imaging and genetic elements that made up the comprehensive assessment of the patient were incorporated. Case presentation: A rare case of Mc Cune-Albright syndrome occurs in a seven-year-old girl with Tanner II-III breasts, vaginal bleeding, axillary and pubic hair, brown spots with milk and bone lesions. She is treated with tamoxifen, which has managed to keep the progression of pubertal development slow. Conclusions: Although this entity is benign in nature and the prevalence is extremely low, early pubertal onset and the compromise of the final size can have a psychological impact on the quality of life and normal development of the individual(AU)

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.

Pubertad precoz y temprana: evaluación y tratamiento / Early puberty: evaluation and treatment

El autor de este artículo repasa las características clínicas de la pubertad precoz y la pubertad temprana, las pruebas diagnósticas indicadas en la evaluación de los pacientes que la presentan y las recomendaciones actuales de tratamiento. (AU)

The author of this article reviews the clinical features of early puberty, the diagnostic tests for the patients ́ evaluation andthe current treatment recommendations. (AU)