The definition of short stature refers to individuals of the same race, sex and age whose height is lower than the average height of the normal population by 2 standard deviations (-2SD) or lower than the 3rd percentile (-1.88SD) in a similar living environment, some of which are normal physiological variants.
There are many factors leading to short stature, including many interactions, and the mechanism of short stature caused by many diseases has not been elucidated so far [Diagnosis] A comprehensive examination must be conducted for children with short stature to clarify the causes in order to facilitate treatment.
A. Medical history Careful inquiry should be made about the pregnancy of the child’s mother; the birth history of the child; the birth length and weight; the growth history; the parents’ puberty development and the short stature in the family.
Physical examination In addition to the routine physical examination, the following items should be correctly measured and recorded: ① the measured value and percentile of current height and weight; ② the annual growth rate of height (at least 3 months of observation); ③ the target height measured from the height of the parents; ④ the BMI value; ⑤ the stage of sexual development.
Routine blood and urine tests and liver and kidney function tests should be routinely performed; karyotype analysis should be performed for girls; to exclude subclinical hypothyroidism, thyroid hormone levels should be routinely tested.
2. Bone
Bone age (BA) is a good indicator for assessing the development of an organism, as the development of bones occurs throughout the growth and development process. Bone age is the bone maturity at each age, and is determined by observing the growth and development of each ossification center in the left wrist, metacarpal and finger bones on the orthopantomograph. Under normal circumstances, the difference between the bone age and the actual age should be between ±1 year, and it is abnormal if it is too far behind or too far ahead.
3. Special examination (1) Indications for special examination ① those whose height is lower than the normal reference value minus 2 SD (or lower than the 3rd percentile); ② those whose bone age is lower than the actual age by more than 2 years; ③ those whose height growth rate is below the 25th percentile (according to bone age), i.e. <7 CM/year growth for children <2 years old; <5 CM/year growth for children over 2 years old; growth hormone stimulation test is required.
(2) Insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) determination Each laboratory should establish its own reference data.
(3) Testing of other endocrine hormones Testing of other hormone choices in children as needed (4) Imaging of hypothalamus and pituitary gland MRI of the skull should be performed in all children with short stature to exclude the possibility of congenital developmental abnormalities or tumors.
(5) Karyotype analysis Karyotype analysis should be performed in all children suspected of having chromosomal aberrations.
(6) IGF-1 production test For children suspected of GH resistance (Laron syndrome), this test can be used to detect GH receptor function. Method 1: Subcutaneous injection of rhGH at 0.075-0.15U/(kg・d) every night for 1 week.
1 week, blood samples were collected before and on the 5th and 8th day after the injection, and IGF-1 was measured; ②Method 2: 0.3
The serum IGF-1 of normal patients will increase more than 3 times the basal value after injection, or reach the normal value corresponding to their age.
Differential diagnosis】 According to the analysis of medical history and physical examination, it is easy to identify short stature caused by malnutrition, psychosomatic family idiopathic short stature, small for gestational age, chronic systemic diseases, etc. The common causes of short stature should be differentiated, such as: chondrodysplasia, hypothyroidism, somatic delayed puberty; clinical attention should also be paid to certain The possibility of certain syndromes, such as Prader-Willi syndrome, Silver-Russeli syndrome, Noonan syndrome, etc., should be noted.