⚠️ Growth Hormone Deficiency (GHD) is insufficient secretion of GH from the anterior pituitary.
It may be isolated or part of panhypopituitarism. Causes include genetic mutations, congenital midline defects, trauma, CNS infections, pituitary tumours, or radiotherapy.
💡 Recognising GHD early in children is critical to optimise final adult height; in adults, treatment improves metabolic, musculoskeletal, and psychological outcomes.
📌 Classification
- By onset:
- ⏳ Congenital: From birth; genetic mutations (GH1, GHRHR), midline defects (e.g., septo-optic dysplasia), pituitary hypoplasia.
- ⚡ Acquired: Later onset due to pituitary adenoma, craniopharyngioma, radiotherapy, traumatic brain injury, infections.
- By age: Childhood vs adult onset; clinical features differ significantly.
🩺 Clinical Features
- 👶 Children:
- 📉 Growth failure: Poor height velocity, short stature.
- 👼 Appearance: Cherubic face, thin hair/skin, ↑ truncal adiposity, prominent forehead.
- 🦴 Skeletal: Delayed bone age, micrognathia in some cases.
- 🩸 Metabolic: Hypoglycaemia, especially if ACTH deficiency coexists.
- ⏱️ Puberty: Delayed/absent secondary sexual characteristics if gonadotropin deficiency present.
- 👨🦳 Adults:
- ⚡ Energy/Mood: Fatigue, depression, poor exercise tolerance, low quality of life.
- 💪 Body composition: Reduced lean mass, ↑ visceral fat, reduced muscle strength.
- 🦴 Bone health: Osteopenia/osteoporosis → ↑ fracture risk.
- ❤️ Cardiovascular/metabolic: Dyslipidaemia, insulin resistance, ↑ cardiovascular risk.
- 🧠 Cognitive/mood: Memory impairment, anxiety, social withdrawal.
🔬 Investigations (NICE NG23 compliant)
- IGF-1: Screening test; low levels suggest GHD but can be normal in mild disease.
- Dynamic GH stimulation tests:
- Insulin Tolerance Test (ITT) – gold standard (contraindicated in seizures, cardiovascular disease).
- Alternatives: Glucagon stimulation, arginine-GHRH, clonidine tests.
- Pituitary MRI: Evaluate adenomas, hypoplasia, empty sella, craniopharyngioma, other sellar lesions.
- Other endocrine tests: Assess for concomitant pituitary hormone deficiencies (TSH, ACTH, LH/FSH, prolactin).
- Bone age X-ray (children): Helps predict growth potential.
⚕️ Management
- Children: Recombinant GH therapy, daily subcutaneous injection → normalise growth velocity and optimise adult height. Dose titrated by IGF-1 levels; continue until epiphyseal closure.
- Adults: GH replacement indicated only in confirmed GHD; improves lean mass, bone density, energy, cardiovascular profile, and quality of life.
- Monitoring:
- IGF-1 levels to adjust dose.
- Fasting glucose, HbA1c, and lipids.
- Periodic DXA scans for bone health.
- Monitor for adverse effects: oedema, arthralgia, carpal tunnel syndrome, insulin resistance.
- Special considerations: Avoid GH therapy in active malignancy; dose carefully in older adults and those with diabetes or cardiovascular disease.
💡 Exam Tips
• In children: short stature, poor growth velocity, delayed bone age → always consider GHD.
• In adults: fatigue, central adiposity, low IGF-1, history of pituitary disease.
• Check for other pituitary hormone deficiencies (TSH, ACTH, gonadotropins) – GHD often part of panhypopituitarism.
• MRI pituitary findings can guide diagnosis and aetiology.
• NICE NG23 emphasises confirmation by stimulation testing before starting GH therapy in adults.
📚 References
- NICE NG23: Growth Hormone Deficiency in Adults
- Shalet SM, et al. 2018. "Guidelines for GH therapy in adults and children." Endocrine Reviews 39:1–31.
- Molitch ME. 2020. "Diagnosis and Treatment of Adult GH Deficiency." Journal of Clinical Endocrinology & Metabolism 105:1–20.
- Childhood GHD: European Society for Paediatric Endocrinology (ESPE) Consensus Guidelines, 2019.
