Hypothalamic–pituitary axis MRI findings in pediatric endocrine disorders: A retrospective study

Abstract

BackgroundMagnetic resonance imaging (MRI) of the hypothalamic–pituitary axis (HPA) is widely used in pediatric endocrinology, yet the clinical relevance of structural abnormalities remains debated.ObjectiveTo assess the diagnostic yield of HPA MRI in children with endocrine disorders and identify clinical/hormonal predictors of clinically relevant findings.MethodsWe retrospectively analysed a total of 202 patients (1 month to 17 years) evaluated from 2018 through 2023 for suspected HPA dysfunction. Diagnostic groups included isolated growth hormone deficiency (IGHD), multiple pituitary hormone deficiency (MPHD), short stature without growth hormone deficiency (SSWGD), central precocious puberty (CPP), central diabetes insipidus (CDI), and pituitary hypersecretion syndrome (PHS). MRI findings were classified as normal, relevant, or incidental. Logistic regression and ROC analysis were used to identify predictive factors.ResultsAbnormal MRI findings were identified in 29.2% of patients (59/202); 14.9% (30/202) were clinically relevant and 14.4% (29/202), incidental. Diagnostic yield (any abnormal finding) was highest in MPHD (100%) and CDI (87.5%), followed by PHS (40.0%), SSWGD (30.8%), CPP (26.4%) and IGHD (23.2%). In IGHD, lower GH peaks on the exercise–propranolol test were significantly associated with abnormal MRI findings (OR, 3.98; 95%CI, 1.53–10.30; P=.026). There were no predictors for CPP. Incidental lesions were most common in CPP and IGHD.ConclusionsMRI showed the highest diagnostic yield in MPHD and CDI. In IGHD, lower GH peak values may help guide selective imaging, while in CPP the lack of reliable predictors supports routine MRI. Multidisciplinary interpretation remains essential to contextualise incidental findings.

ResumenIntroducciónLa resonancia magnética (RM) del eje hipotálamo–hipofisario (EHH) es habitual en endocrinología pediátrica, pero la relevancia clínica de las anomalías estructurales es controvertida.ObjetivoEvaluar el rendimiento diagnóstico de la RM del EHH e identificar predictores clínicos/hormonales de hallazgos relevantes.MétodosEstudio retrospectivo de 202 pacientes (1 mes–17 años) evaluados en 2018–2023 por sospecha de disfunción del EHH. Grupos diagnósticos: deficiencia aislada de hormona de crecimiento (GH) (IGHD), deficiencia múltiple de hormonas hipofisarias (MPHD), talla baja sin déficit de GH (SSWGD), pubertad precoz central (CPP), diabetes insípida central (CDI) y síndrome de hipersecreción hipofisaria (PHS). Las RM se clasificaron como normales, relevantes o incidentales. Se aplicaron regresión logística y curva ROC para identificar predictores.ResultadosSe observaron hallazgos anómalos en el 29,2% (59/202); relevantes 14,9% (30/202) e incidentales 14,4% (29/202). El rendimiento (cualquier hallazgo anómalo) fue mayor en MPHD (100%) y CDI (87,5%), seguido de PHS (40,0%), SSWGD (30,8%), CPP (26,4%) e IGHD (23,2%). En IGHD, picos más bajos de GH en la prueba ejercicio–propranolol se asociaron significativamente con RM anómala (OR 3,98; IC 95% 1,53–10,30; p=0,026). No se identificaron predictores en CPP. Las lesiones incidentales fueron más frecuentes en CPP e IGHD.ConclusionesLa RM mostró mayor rendimiento diagnóstico en MPHD y CDI. En IGHD, picos de GH más bajos podrían guiar una indicación selectiva; en CPP, la ausencia de predictores respalda la RM sistemática. La interpretación multidisciplinar es esencial para contextualizar los hallazgos incidentales.