precocious puberty
Introduction
Introduction Precocious puberty is a common developmental abnormality in the pediatric endocrine system. It refers to the abnormality of the second sexual development of the girl before the age of 8 years. Central precocious puberty (CPP) is due to the increased secretion and release of gonadotropin-releasing hormone (GnRH) in the hypothalamus, which activates the function of the glandular axis in advance, leading to gonadal development and secretion of sex hormones, making the internal and external genital development and The sexual characteristics are presented. CPP is also known as GnRH-dependent precocity, and its progression is progressive until the reproductive system matures.
Cause
Cause
1. Central nervous system organic lesions.
2. Peripheral precocious puberty is transformed.
3. Idiopathic CPP (ICPP) has no organic lesions. 80% to 90% of female children are ICPP, while males are opposite, and more than 80% are organic. It is speculated that this part of precocious puberty is closely related to the stimulation of environmental endocrine disruptors.
Examine
an examination
Related inspection
Estradiol gestational estriol determination (E3) urine estradiol urine 17-hydroxy-corticosteroid (17-OH-CS)
1. Second sexual characteristics appear in advance
Before the girl was 8 years old, the boy was 9 years old.
2. Serum gonadotropin levels rise to pubertal levels.
(1) Basic value of gonadotropin: If the secondary sexual characteristics has reached the middle-age level, the serum luteinizing hormone (LH) base value can be used as a preliminary screening, such as >5.0 IU/L, to determine its gonad axis. It is no longer necessary to perform a gonadotropin-releasing hormone (GnRH) challenge test.
(2) GnRH challenge test: This test is an important diagnostic tool for the function of the gonad axis and the gonadotropin basal value is not elevated. GnRH can increase the release of gonadotropin secretion, and the peak of its excitation can be used as a diagnostic basis.
The cut-poit value of the LH excitation peak for diagnosing CPP: LH peak>5.0 IU/L, LH peak/FSH peak>O.6 can diagnose CPP, such as LH bee/FSH peak>O.3, but <0.6 At the time, it should be closely followed by clinical follow-up and repeated tests if necessary to avoid missed diagnosis.
3. Gland enlargement
The girl sees the ovarian volume >1ml under B-ultrasound, and can see multiple follicles >4mm in diameter. The testicular volume of the boy is 4ml, and it progressively increases with the course of the disease.
Diagnosis
Differential diagnosis
Simple breast early development
That is, partial central precocious puberty (PICPP), FSH increased significantly after GnRH challenge (normal pre-puberty girls will also increase after challenge), but LH elevation is not obvious (most L), and FSH / LH> 1. However, it is worth noting that PICPP will be converted to CPP without any clinical warning. Therefore, regular follow-up is required after diagnosis of PICPP, especially if the breast is repeatedly enlarged or persistent, and the test is repeated if necessary.
2. CPP transformed from non-central precocious puberty
Such as congenital adrenal hyperplasia, McCune-Albright syndrome, etc., must pay attention to monitoring the occurrence of CPP in the treatment of primary disease.
3. Precocious puberty associated with congenital hypothyroidism
It is a special type of precocious puberty. The baseline value of blood LH in early children is elevated, but it does not increase after GnRH stimulation. It is converted to true CPP after a long course of disease. Short stature is an important feature.
