From the Guidelines
Diagnosing growth disorders in children and adolescents requires a comprehensive approach that prioritizes the measurement of serum IGF1 levels and GH response to an oral glucose load, as these tests are crucial for identifying GH excess and guiding further management. The diagnosis of growth disorders involves a combination of physical examinations, laboratory tests, and imaging studies. Initial evaluation includes accurate height and weight measurements plotted on growth charts, assessment of growth velocity, and determination of bone age through wrist X-rays 1.
Key Diagnostic Tests
- Blood tests are essential, including complete blood count, comprehensive metabolic panel, thyroid function tests (TSH, free T4), IGF-1 and IGFBP-3 to assess growth hormone function, and karyotyping for suspected genetic disorders like Turner syndrome 1.
- Elevated serum IGF1 levels in relation to age-adjusted, sex-adjusted, and Tanner stage-matched normal ranges are a reliable marker for GH excess 1.
- GH response to an oral glucose load is also a critical test, with failure to suppress GH levels below 1 μg/l indicating potential GH excess 1.
- Stimulation tests for growth hormone deficiency may be performed using agents like clonidine, arginine, or insulin to evaluate the pituitary's ability to release growth hormone.
Specialized Tests
- Additional specialized tests include genetic testing for conditions like Prader-Willi syndrome or Noonan syndrome, celiac disease screening, and advanced imaging such as MRI of the brain to evaluate the pituitary gland and hypothalamus 1.
- Dynamic pituitary assessment of possible hypofunction and hyperfunction of other anterior pituitary hormones is recommended in children and adolescents with GH excess 1.
- Clinical evaluation for associated syndromic causes of somatotrophinomas, such as Carney complex, McCune–Albright syndrome, and MEN1 or MEN1-like disease, is also essential 1.
Interpretation of Test Results
- Biochemical results should be interpreted within a clinical assessment of phenotype, including height velocity, pubertal stage, and bone age 1.
- Both GH and IGF1 levels should be monitored at baseline and during follow-up in children and adolescents with GH excess 1.
- The diagnosis of GH excess in the context of syndromic diseases is identical to sporadic cases of acromegaly, and biochemical screening for pituitary hormone excess is recommended in these cases 1.
From the FDA Drug Label
According to current standards, confirmation of the diagnosis of adult GHD in both groups involves an appropriate GH provocative test with two exceptions: (1) patients with multiple pituitary hormone deficiencies due to organic disease; and (2) patients with congenital/genetic GHD.
The tests to diagnose growth disorders include GH provocative tests. These tests are used to confirm the diagnosis of adult Growth Hormone Deficiency (GHD) in patients, with some exceptions, such as those with multiple pituitary hormone deficiencies due to organic disease, or congenital/genetic GHD 2.
From the Research
Diagnosis of Growth Disorders
To diagnose growth disorders, several tests and evaluations can be used, including:
- Medical history and physical examination to identify signs and symptoms of growth hormone deficiency (GHD) 3
- Biochemical testing, such as insulin-like growth factor 1 (IGF-1) levels, to assess growth hormone function 4
- Imaging studies to evaluate the pituitary gland and other structures involved in growth regulation 3
- Growth hormone stimulation tests to assess the body's ability to produce growth hormone 3
Growth Hormone Stimulation Tests
Growth hormone stimulation tests are used to diagnose GHD, but they have several limitations, including:
- Inaccuracy and imprecision in test results 3
- Difficulty in performing the tests 3
- Variability in peak growth hormone cut-offs depending on age and test used 3
- Individual patient factors that can affect test results, such as differences in IGF-1 assays 3
Investigation of Growth Disorders in Adolescents
In adolescents, growth disorders can be investigated using:
- Careful history and examination to identify signs and symptoms of growth disorders 5
- Targeted investigations, such as hormone level tests and imaging studies, to confirm the diagnosis 5
- Accurate pubertal staging to assess growth and development 5
- Consideration of genetic potential and physiological variants to distinguish between normal and abnormal growth patterns 5
Treatment Guidelines for Growth Disorders
Treatment guidelines for growth disorders, including GHD, idiopathic short stature, and primary IGF-1 deficiency, have been developed to provide recommendations for clinical management, including:
- Use of growth hormone therapy to promote growth and development 6
- Use of recombinant IGF-1 therapy as an alternative to growth hormone therapy in some cases 6
- Consideration of individual patient factors and risks and benefits of treatment 6
Growth Abnormalities in Chronic Inflammatory Conditions
Growth abnormalities can occur in children with chronic inflammatory conditions, such as juvenile idiopathic arthritis and inflammatory bowel disease, due to:
- Impaired growth hormone function and IGF-1 levels 7
- Direct effects of inflammation on the growth plate and chondrogenesis 7
- Use of glucocorticoids and suboptimal nutrition, which can contribute to growth failure 7
- Potential benefits of recombinant human growth hormone therapy to promote catch-up growth 7