hermaphroditism
Introduction
Introduction Sexual malformation refers to the sexual performance of an individual's sexual organs. The reason for this is due to sex chromosome aberrations, and abnormal secretion of androgen leads to abnormal development of sexual organs in the embryo. If the same body has both testicles and ovaries, the external genitalia and the second sexual characteristics are between the two sexes, called true hermaphroditism. If the gonads are not consistent with the external genitalia, they are called pseudohermaphroditism. For example, the external genitalia is similar to a female and the internal genitalia is a testicular called a male pseudohermaphroditism. On the contrary, the external genitalia is similar to the male, and the internal genitalia is the ovary, which is called female pseudohermaphroditism.
Cause
Cause
1. Sex chromosome aberrations:
In the process of embryonic development, the sexual organs are differentiated into male or female, and the determinants are initially controlled by genetic factors, such as the genomic type of the newborn individual is 46, XX, that is, the development into a female; the karyotype is 46, XY, then Develop into a man. Because the Y chromosome has a genetic gene that determines the differentiation of the original gonads into testes, and the X chromosome lacks such genes. If the number and structure of sex chromosomes are distorted, it will inevitably lead to disorder of sexual differentiation.
2. Abnormal secretion of androgen during embryonic period:
When the primordial gonads differentiate into the testis under the control of genetic factors, the cortex is degraded, but the medulla is well developed, so both the interstitial cells and the adrenal cortex produce a considerable amount of androgen. Due to the action of androgen, the primordial reproductive duct and the external genital primordia are differentiated towards males. If the gonads differentiate into the ovary, the adrenal cortex produces less androgen, and the genital tube and the external genital primordium differentiate into the female direction. When the genetic sex is male, the androgen deficiency is caused for some reasons, or the genetic sex is female. Due to excessive androgen, the differentiation of reproductive tract and genital primordia may be caused.
3. Other factors:
The reduction in the number of primordial germ cells in the embryo also masculinize the genetic female. The decrease in the number of primordial germ cells can cause the development of the primordial gonad cortex, the deep medulla forms testicular components, and the mesenchymal cells produce androgen, which causes the primordial reproductive duct and the external genital primordium to differentiate into males.
Examine
an examination
Related inspection
Y chromatin chromosome gestational estriol assay (E3) urinary 17-ketone corticosteroid (17-KS)
(1) Medical history:
Pay attention to whether there are similar patients in the family; whether the mother has a history of taking male hormones during conception.
(two) symptoms and signs:
1. Observe the patient's appearance, physical development and development of secondary sexual characteristics such as beard, mane, pubic hair, breast and sound. Understand the patient's menstrual condition.
2. External genital examination:
The external genitalia of the hermaphroditism is artificially divided into 5 types:
Type I: only the clitoris increases in the external genitalia;
Type II: the clitoris is enlarged and has a wider funnel-shaped urogenital sinus, and the vagina has a common opening with the urethra;
Type III: urogenital sinus is narrow, but still funnel-shaped;
Type IV: a small urogenital sinus opening at the base of the penis;
Type V: The urogenital sinus opening is at the tip of the penis, as in a normal male.
(3) Laboratory inspection:
1. Sexual chromatin examination and karyotyping.
2. Determination of testosterone, 5a-dihydrotestosterone, serum estradiol, progesterone and luteinizing hormone in plasma. 24 h urine 17-ketosteroids and gestational triol, HY antigen serological examination.
(4) X-ray inspection:
X-ray of the wrist, urogenital sinus angiography, retroperitoneal angiography, CT examination of adrenal gland size changes.
(5) Surgical exploration and gonadal biopsy.
Diagnosis
Differential diagnosis
(1) True hermaphroditism:
True hermaphroditism is rare, and there are two hypoplastic gonads (ovary and testis) in an individual. In the scrotum (labia), the groin testis on one side of the groin or abdomen (pellet), the ovary or testicle on the other side, or the ovarian testicles on both sides. There are uterus in the pelvis, most of which are underdeveloped. There may be periodic hematuria and lower abdominal pain or scrotal pain. Most of the patients were male, breast development was more common, and some female signs such as slim body, mane, pubic hair and beard were rare, the throat was flat, and the sound was sharp. The external genitalia is more common in the dish type IV. Sexual chromatin was 80% positive. The karyotype is 60% 46, XX, 20% is 46, XY, and the others are 46, XX/XY chimeric. HY antigen is positive. Serum female hormones increased periodically, consistent with changes in women's menstrual cycle.
(2) Male pseudohermaphroditism:
The patient has a Y chromosome, and the internal genitalia is a single incompletely developed testicle with varying degrees of feminization of the external genitalia.
According to the degree of sex of the external genitalia, it is divided into 3 types:
1. Male external genital type: penis development is close to normal, but there is hypospadias; often there are cryptorchidism or inguinal hernia, there are immature uterus and fallopian tubes in the hernia sac. The appearance is male and has a second sexual characteristic. The cause of the disease is that the male fetus fails to inhibit the development of the secondary renal tube during the embryonic stage, and forms a hypoplastic uterus and fallopian tubes. This type is also known as the secondary renal tube retention syndrome.
2. Female external genital type: also known as complete testis, feminine, chromosome karyotype is 46, XY. There is a testicle, the biosynthesis of testosterone is normal, and the concentration of testosterone in the blood is normal.
The testicles can be found in the abdominal cavity, labia majora or inguinal hernia sac. The epididymis and vas deferens can be present at the same time. Some patients are missing. The external genital morphology is completely female, with clitoris, labia and pseudovaginal, but no ovaries, fallopian tubes and uterus. The lesion is that the embryonic organ tissue cells completely lack the androgen receptor adhesion protein, so that the genitourinary sinus and the external genital primordia develop into female external genitalia. Adolescence can develop into normal female breasts and female body. But there is no menstrual cramps.
3. Female phenotype of external genital area: short penis like hypertrophic clitoris, accompanied by penis scrotum-type hypospadias; scrotum rupture like labia majora, containing testis; false vaginal, urogenital sinus deformity; no female uterus and accessories. Testosterone synthesis disorders, incomplete testicular feminization, Reifenstein syndrome, pseudovaginal scrotal hypospadias syndrome and asymmetrical mixed gonadal dysplasia are all female phenotypes of the external genitalia.
4. In addition, there is a male pseudohermaphroditism, although the chromosome is 46, XY, but there is no testis, no ovaries, the external genitalia is female. It is called adenopathy. The pathogenesis may be due to genetic mutations that cause the development of embryonic genital organs to be completely inhibited. Some patients have a family history and may be autosomal recessive disorders.
(3) Female pseudohermaphroditism:
The patient's chromatin was positive, the karyotype was 46, XX, and the body had ovary, fallopian tube and uterus, but there were genital manifestations of external genital malformation and shape and precocity. Congenital adrenal hyperplasia and adrenal cortical tumors can secrete too much androgen, or pregnant mothers taking male hormone drugs can make the embryonic genital tract and external genital primordia differentiate into males, and the patient's external genital malformation For the clitoris hypertrophy, the labia majora merges like a split-like scrotum, and the vagina and the urethra have a common opening, leaving a funnel-shaped urogenital sinus. The masculinity is characterized by rapid growth and growth, and the age of the epiphysis is advanced; pubic hair appears earlier. Mane and beard, throat is enlarged, voice is thicker; breast is not developed. No menstruation, clitoris can be erect. In addition, a small number of patients can develop high blood pressure. The increase of 24 h urinary 17-ketosteroids and gestational triol is one of the characteristics of this disease.
The above three types of hermaphroditism are difficult to distinguish only by external genitalia and secondary sexual characteristics, and can be differentially diagnosed by laboratory and other special examinations.
