Hypospadias is a malformation of the penis in which the urethra opens proximal to the normal urethral opening due to various reasons that cause the urethra to not reach its normal position.
[Etiology and pathogenesis
(1) Embryological causes: Hypospadias is formed when the urethral groove is not fully fused during the embryonic period due to endocrine abnormalities or other reasons.
(2) Genetic inheritance, there is a clear family tendency for the development of hypospadias, and the disease is inherited from multiple genes. 20%-25% of clinical cases have genetic factors.
(3) Hormonal effects There are reports of impaired serum testosterone production in children with severe hypospadias whose urethral orifice is located proximal to the penile body. It is also possible that genital abnormalities are secondary to maternal hormone intake during pregnancy.
During urethral development, the urethral groove is incompletely fused, thus causing the urethra to open proximal to the normal urethral orifice. Various types of clinical hypospadias are formed.
[Diagnosis
(A) Symptoms
1. Urination from the ventral side of the penis. In severe cases, standing up to urinate wet pants.
(B) Physical signs
1. Abnormal urethral opening.
2. Downward curvature of the penis.
3. Capitellar prepuce and prepuce tethering agenesis, where the prepuce is piled up on the dorsal side of the penis with a V-shaped agenesis on the ventral side.
(iii) Laboratory tests
1. Check autosomes, normal sex chromosomes male 46XY, female sex chromatin positive rate in more than 10%, while male in less than 5%.
2, urinary 17 ketones, 17 hydroxyprogesterone steroid excretion measurement and other endocrine tests.
(IV) Differential diagnosis
1. Abnormal adrenal sex characteristics (female pseudohermaphroditism) The disease is almost always caused by adrenal cortical hyperplasia. Vulvar examination reveals an enlarged clitoris like a penis with hypospadias. The urogenital sinus remains and the opening communicates with the urethra anteriorly and with the uterus posteriorly. Sex chromosome 46XX, sex chromatin positive, urinary 17 ketone, 17 hydroxyprogesterone increased.
2.True hermaphroditism The appearance is similar to hypospadias combined with cryptorchidism. Urinary 17 ketone is normal. Half of the sex chromosomes are 46XX, 30% are 46XX/46XY chimerism, 20% are 46XY. gonadal examination shows that the gonads have both testes and ovaries in the body.
3, male pseudohermaphroditism chromosome 46XY, sex chromatin negative, but the internal and external genital development is not normal, external genital appearance can be like male or female.
4.Mixed gonadal dysgenesis is the second common cause of external genital abnormalities in the neonatal period. The most common chromosome karyotype is 45XO/46XY, which shows that one side of the gonad is normal testis and the other side is primitive striped gonad. 60% of patients show incomplete masculinization and small penis at birth, and the external genitalia are more sensitive to androgen stimulation.
[Treatment].
Three criteria for the treatment of hypospadias: 1 orthotropic urethral orifice; 2 adequate correction of penile recurvature; 3 near normal penile appearance. Can stand to urinate and have a normal sexual life in adulthood.
Surgery is usually done after one year of age, at least before entering kindergarten or school to reduce the psychological stress of the parents or the sick child. The surgical methods are divided into two categories according to the presence or absence of penile hypospadias.
I. No or mild penile curvature
1, penile head type can be used urethral advancement penile head shaping (MAGPI method), if there is a significant downward curvature of the penile head can also be corrected by white membrane tightening on the dorsal side of the penis.
2.Coronary sulcus, penile body anterior type Urethral orifice basal flap (Mathieu) method.
3, penile body type Covered island foreskin flap urethroplasty (onlay island flap). Since many penile hypospadias are not caused by abnormal development of the urethral plate, the method of correcting hypospadias in combination with dorsal white membrane tightening can be applied to many patients.
4, urethral plate coiled tube urethroplasty (Snodgrass procedure) is gradually becoming widely used.
II. Combined penile hypospadias
Duckett tipped island flap urethroplasty is mostly chosen. Severe cases of hypospadias need to apply the Duckett+Duplay method.
Complications and treatment
1. Urethral fistula is the most frequent comorbidity after urethroplasty. The recognized incidence is 15% to 30%, and even if the operator is skilled, the incidence is 5% to 10%. Do not rush to deal with urethral fistula after it is found, but wait for more than 6 months after surgery, after the local skin scar has softened and the blood supply has been rebuilt. And small urethral fistulas still have the possibility of self-healing.
2. Urethral stricture mostly occurs at the urethra and anastomosis of the penile head segment. Early stenosis within 3 months after surgery can be solved by urethral dilatation, if it is not effective, surgery is needed.
3. Urethral dilatation is most often seen in cases of tubular urethroplasty with Duckett’s transverse cut foreskin island flap. For small diverticular dilatation secondary to urethral stricture, most of them can be improved after the stricture is released. In contrast, large diverticular urethral dilatation should be treated by first eliminating the cause and then cutting the diverticulum-like dilated urethral wall to shape the urethra.
Prevention
There is no way to prevent it
Suburethral cleft treated by our treatment group Pre-operative
Post-operative
Before surgery
End of surgery