Congenital hypothyroidism

Disease Description (Causes and Symptoms)

• Definition summary: Growth hormone deficiency is a condition in which insufficient growth hormone (GH) is secreted by the pituitary gland (or hypothalamus), resulting in delayed growth and metabolic abnormalities.
• Main causes
  • Congenital defects (such as hereditary abnormalities in pituitary development)
  • Pituitary or hypothalamic tumors, or damage following surgery/radiation therapy
  • Sequelae of traumatic brain injury (TBI), encephalitis, meningitis, etc.
  • Other inflammatory diseases, head injury at birth, etc.
• Pathophysiology summary: GH deficiency leads to reduced production of IGF‑1 in the liver, affecting bone growth (bone metabolism), body composition, and fat, carbohydrate, and lipid metabolism.
• Main symptoms
  • Children: Height at or below the 3rd percentile or reduced annual growth velocity (less than 4 cm over 1 year in children aged 3 years or older), delayed bone age, abdominal obesity (upper-body enlargement), youthful appearance (infant-like facial features), fatigue and reduced energy
  • Adolescents/adults: Dyslipidemia, reduced muscle mass, increased body fat, reduced bone mineral density, delayed sexual development (during adolescence)
  • Systemic symptoms: Easy fatigue, reduced energy, skin that appears youthful and fragile

Treatment Methods and Precautions

• Standard treatment
  • Subcutaneous injection of recombinant human growth hormone (rhGH) (usually administered regularly before bedtime)
  • Children: Dose is calculated based on body weight/body surface area (generally started at a low weight-based dose and adjusted according to response)
  • Adults: When deficiency is confirmed, treatment is started at a low dose and adjusted to the target IGF‑1 level
• Additional treatment/management
  • If an underlying disease (such as a tumor) is present, surgical or radiation treatment or coordinated endocrinological treatment is required
  • If bone mineral density is reduced, osteoporosis management (calcium and vitamin D, and medication if necessary)
  • Establishment of growth goals reflecting predicted growth and bone age, with regular monitoring
• Monitoring (recommended)
  • Early in treatment: Check IGF‑1, fasting blood glucose/hemoglobin A1c, thyroid function, electrolytes, and clinical symptoms (edema, headache, etc.) at 1–3 month intervals
  • After stabilization: IGF‑1 and clinical evaluation at 6–12 month intervals
  • Children: Regularly check bone age (X‑ray) and growth velocity
  • Regular brain MRI if there is a history of or suspicion of a pituitary tumor
• Precautions / contraindications
  • Contraindicated in the presence of active malignancy (careful evaluation after the tumor is controlled)
  • Untreated severe endocrine disorders (e.g., adrenal insufficiency) require treatment first
  • Monitor for adverse effects: Headache and vomiting (signs of increased intracranial pressure), edema and joint pain, hyperglycemia or insulin resistance, skeletal complications in children (immature growth plate problems, SCFE — slipped capital femoral epiphysis), and possible progression of scoliosis
  • Discontinuation during pregnancy is generally recommended

Outpatient Visit Checkpoints (Items to Bring and Things to Confirm)

• Materials to bring
  • List of current medications (including prescription/nonprescription drugs and supplements)
  • Growth records (height and weight charts from the past several years, and a child’s growth chart if possible)
  • Previous test results: Bone age (X‑ray), IGF‑1/IGFBP‑3 levels, hormone test results, and brain MRI (if available)
  • Records of previous surgery, radiation therapy, or severe infections (such as meningitis)
• Symptom changes to record for the consultation
  • Height increase over the past 6–12 months, degree of fatigue, changes in appetite and weight, and whether puberty has begun (menstruation/secondary sexual characteristics)
  • Symptoms that may indicate increased intracranial pressure, such as headache, visual changes, and vomiting
• Other preparations
  • Insurance/cost-related information (growth hormone treatment involves long-term costs, so advance confirmation is recommended)

Example question sentences (for preparing what to ask the doctor)

• Bringing a printout of the growth curve from the past several years can make the consultation easier.
• If you have previous brain MRI or endocrine test results, prepare copies.

Examples of General Questions to Ask the Doctor

• "What are the expected benefits and possible side effects of this medication (growth hormone)?"
• "How soon after starting treatment (within how many months) can we expect an improvement in growth velocity?"
• "How long does treatment usually last, and what are the criteria for ending it?"
• "Which tests should be performed during treatment, and how often?"
• "What long-term effects could this treatment have on bone mineral density or metabolism?"

Examples of Disease-Specific Questions

• For children (for parents): "Based on my child’s current growth velocity and bone age, what is the estimated final height? Approximately how much additional height (e.g., how many cm) can be gained through treatment?"
• For adults: "When GH deficiency is suspected in an adult, which tests (e.g., stimulation tests) are used to confirm the diagnosis? To what extent can GH replacement therapy help improve metabolism and quality of life?"

References (Key Points for Diagnosis and Treatment)

• Diagnosis involves clinical evaluation of delayed growth + bone age assessment + evaluation of GH secretion (stimulation test) and measurement of IGF‑1; brain MRI may be used to identify the cause when necessary.
• A single random GH measurement is not suitable for diagnosis (a stimulation test is required).
• Treatment is standardized rhGH replacement therapy, and its effectiveness and adverse effects must be monitored regularly.