EC Paediatrics

Introduction: Pediatric growth disorders such as Growth Hormone Deficiency (GHD), Idiopathic Short Stature (ISS), Turner Syndrome, and systemic conditions like chronic kidney disease (CKD) are evaluated using the GH-IGF-1 axis. The diagnostic utility of IGF-1 Generation and GH Stimulation Tests remains crucial yet variable across conditions. This review addresses the sensitivity and specificity of these diagnostic methods, their integration with biomarkers, and their predictive value.

Objectives: To assess the diagnostic performance of IGF-1 Generation and GH Stimulation Tests, analyze the role of biomarkers (e.g. IGFBP-3, ALS, IGF-II), and evaluate their predictive capabilities for long-term growth outcomes.

Methods: A systematic review of 68 studies involving 3,200 pediatric patients was conducted. These studies evaluated IGF-1 dynamics, GH stimulation responses, and biomarker utility across various conditions, including GHD, ISS, Turner Syndrome, SGA, and Thalassemia Major. Statistical metrics such as sensitivity, specificity, and predictive accuracy were synthesized to highlight diagnostic robustness. Methodological rigor was ensured through PRISMA guidelines.

Results: GH Stimulation Tests demonstrated high sensitivity (90-100%) for GHD, while IGF-1 Generation Tests showed moderate sensitivity for ISS (30-50%) and Turner Syndrome (40-60%). Biomarkers like IGFBP-3 enhanced diagnostic specificity, particularly in conditions with receptor insensitivity. Early IGF-1 responses correlated strongly with long-term growth outcomes, making them a reliable predictor of GH therapy success. Variability in IGF-1 responses was observed due to puberty, nutritional status, and systemic factors.

Discussion: The integration of IGF-1 Generation Tests with GH Stimulation Tests and biomarkers addresses diagnostic gaps, especially in systemic and receptor-related growth impairments. Studies by Shen., et al., Ranke., et al., and Kim., et al. consistently highlight the predictive value of IGF-1 responses during therapy. However, international variability in diagnostic efficacy underscores the need for tailored protocols. Advancements in precision diagnostics, including biomarker polymorphisms, promise to refine sensitivity and specificity further.

Conclusion: The IGF-1 Generation and GH Stimulation Tests are complementary tools in diagnosing pediatric growth disorders. Biomarker integration enhances diagnostic precision, while early IGF-1 responses reliably predict growth outcomes. Tailored diagnostic frameworks informed by individual and population-specific factors are recommended to optimize clinical outcomes and advance endocrine research.

 Keywords: Growth Hormone Deficiency; IGF-1 Generation Test; Biomarkers; Pediatric Growth Disorders; Diagnostic Sensitivity

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