Growth Hormone Deficiency in Children

Growth hormone (GH) is released from the anterior pituitary under hypothalamic control. It stimulates production of insulin-like growth factor 1 (IGF-1), especially in the liver and growth plates. GH and IGF-1 together support linear bone growth, protein synthesis, and normal body composition. A child with inadequate GH secretion usually grows more slowly over time. The problem is not simply being short. The more revealing pattern is a declining growth velocity: the child crosses downward through height percentiles that they had previously followed. GH deficiency may be isolated, or it may occur with deficiencies of thyroid-stimulating hormone, adrenocorticotropic hormone, gonadotropins, or antidiuretic hormone. This distinction matters because a child with multiple pituitary hormone deficiencies can develop urgent complications such as hypoglycemia or adrenal insufficiency. The cause may be congenital or acquired. Pituitary or hypothalamic malformations, genetic conditions, tumors, infiltrative disease, head trauma, cranial irradiation, and prior neurosurgery can disrupt the hypothalamic-pituitary pathway. Some children have no identifiable structural cause. Linear growth can occur only while the epiphyseal plates remain open. Somatropin cannot increase height after epiphyseal closure.