Hypospadias is a penile malformation due to the underdevelopment of the anterior urethra, resulting in the urethral opening not reaching its normal position, i.e. the opening appears on the ventral side of the penis proximal to the normal urethral opening, or even on the scrotum, accompanied by a downward curvature of the penis. Hypospadias is a common congenital malformation in the pediatric genitourinary system and is the main disease causing the curvature of the penis. Although the diagnosis is relatively easy, the treatment is complicated and the treatment period is prolonged due to many postoperative complications, and parents are very confused. The following is an introduction to hypospadias from etiology, symptoms, comorbidities, diagnosis, and treatment.
I. Etiology of hypospadias
Normal external genitalia are completed in the 12th week of embryonic development, and the urethra gradually fuses from the ventral side of the penis from near to far to form the urethra up to the glans penis. Due to the lack of embryonic dihydrotestosterone or its insufficient action, the urethral groove does not completely close to the tip of the penile head and stops at different stages and different types of hypospadias occur. The incidence of hypospadias is about 1 case per 300 male infants, and there is a clear familial tendency for the development of hypospadias to be inherited from multiple genes. There is also a relationship with maternal factors, and environmental factors.
Symptoms of hypospadias
The typical hypospadias has three characteristics.
1. Ectopic urethral orifice:The urethral orifice can be ectopic to any part of the normal urethral orifice proximal to the perineum, and part of the external urethral orifice is narrow. The urinary line is usually downward and backward during urination, and the child often urinates in a squatting position.
2. Penile recurvature: The penis is bent ventrally, and more than one-third of the children have obvious recurvature. According to the angle between the head of the penis and the longitudinal axis of the penis body, the penis can be divided into: mild <15 degrees; moderate >35 degrees. Moderately severe has difficulty in sexual intercourse in adulthood.
3, abnormal foreskin distribution:The ventral foreskin of the head of the penis is V-shaped defective because it fails to fuse in the midline, the foreskin tether is absent, and the foreskin is cap-like accumulation on the dorsal side of the head of the penis.
Suburethral cleft is divided into four types according to the location of the urethral opening.
1. Head of penis, coronal groove type: The urethral orifice is located on the ventral side of the coronal groove, often in the shape of a V-shaped cleft, and can be complicated by urethral stricture, with a bloated dorsal foreskin but no foreskin and tether on the ventral side. The head of the penis is exposed and more slender-like. The penis is bent ventrally, but to a lesser extent, and mostly does not affect intercourse and standing urination.
2.Penile type: The urethral orifice is located at any part of the ventral side far from the junction of the coronal groove to the penile scrotum, and the distal urethra is absent as an open urethral plate, not forming a tube. The penis is bent to the ventral side, and the closer the urethral orifice is to the side the more serious the bending is, affecting sexual intercourse and standing to urinate.
3, penis scrotum type: the urethral orifice is located in the midline of the scrotum, the scrotum is split like the female labia majora, the penis is bent seriously, need to squat to urinate. The penis is short and flat, resembling the female clitoris. Some of the affected children’s testicles do not descend into the split scrotum or form a penis-scrotum transposition.
4. Perineal type: The urethral orifice is located in the perineum, scrotal division is obvious, cryptorchidism may be combined, and the penis is small and curved, resembling a fat clitoris. The whole genital appearance is blurred, and the development resembles female vulva, so some children are mistaken as female by their parents and delay treatment.
Comorbidities of hypospadias
The most common comorbidities of hypospadias are inguinal hernia and incomplete testicular descent, each accounting for about 10%. A small number of suburethral clefts are combined with anorectal malformations, cardiovascular malformations, and chest wall malformations. Severe hypospadias is often complicated by prostatic sac, penile torsion, micropenis and repeated urethra.
Diagnosis of hypospadias
Most of the diagnosis of hypospadias is known at a glance, but some of the hypospadias need to be diagnosed by auxiliary examination. Hypospadias of penile-scrotal and perineal type is often complicated by scrotal splitting and blurring of external genital organs. A chromosomal karyotype must be done to determine the sex of the affected child, so it needs to be associated with diseases such as abnormal adrenal sex characteristics, true hermaphroditism, male pseudohermaphroditism and mixed gonadal dysplasia. If necessary, urethroscopy is also done to understand the development of male internal genital organs; intravenous pyelogram or excretory cystourethrography can be done to understand whether congenital anomalies such as duplicated kidney and ureteral reflux are combined.
V. Treatment of hypospadias
The surgery of hypospadias is complicated and the rate of postoperative complications is high. There are close to 10 common surgical procedures for hypospadias, which need to be decided according to the specific condition of the child, and there are large individual differences. The goal of surgery is to completely correct the hypospadias, to bring the urethral opening to the head of the penis in a positive position, and to make the appearance of the penis nearly satisfactory. Urethral fistula is the most frequent complication after urethroplasty and can be found mostly after removal of the urethral catheter after surgery, but there are also small fistulas with delayed appearance. Urethral fistula repair is mostly done more than 6 months after surgery, after the local skin scar has softened and the blood supply has been reestablished. Next is urethral stricture, which mostly occurs in the urethra and anastomosis out of the penile head segment. Early stricture 1-2 months after surgery can be lifted by urethral dilation, and if it is not effective, the strictured urethra needs to be surgically incised again and urethroplasty is performed at a later date. Again for urethral dilatation, often secondary to urethral stricture, the proximal urethra is dilated due to urethral stricture, and some form diverticulum-like dilatation, which also requires surgical treatment.
Parents should be reminded that hypospadias surgery is best done before the baby enters daycare. In addition, if hypospadias is caused by chromosomal abnormalities, hormonal or enzyme deficiencies, surgery only corrects the appearance, but also requires treatment for endocrine causes so that the penis will grow strong and the child will have a happy and sexual life in the future.