Analysis in the influence factors of urethroplasty in DSD

Abstract

Background: At present, there is no specific research on the factors affecting the success rate of urethroplasty in patients with DSD. The purpose of this study is to explore the factors affecting the success of urethroplasty in DSD patients, and to provide some reference for the surgical treatment of DSD patients undergoing urethroplasty.

Method: We reviewed patients with DSD who underwent urethroplasty from January 2016 to December 2019 retrospectively. Patients were divided into four groups: the successful group, the urethrocutaneous fistula group, the urethral diverticulum group, and the urethral stricture group. Risk factors were determined from the following data included the DSD classification, the age of first operation, length of urethral defect, degree of hypospadias, cryptorchidism, micropenis, gonad type, hormone therapy before operation, transposition of penis and scrotum, surgical strategy, urethral covering material, and postoperative catheter removal time. We explored the difference of each factor between four groups through the comparative study of single factor and multifactor logistic regression analysis of related factors.

Result: 122 cases were enrolled in this group (n = 122), 12 cases were lost to follow-up. Median follow-up was 28 months (12-55 months).We found the success rate of operation decreased with longer urethral defect (B = - 0.473, P = 0.005). The success rate of operation was higher in staged operation and TPIT (TPIT = Transverse Preputial Island Tube operation)-related operation than primary operation (B = 1.238, P = 0.006) and TPIT-nonrelated operation (B = 2.293, P = 0.001). Although there was a significant difference between the age of the first operation and the occurrence of urethrocutaneous fistula (P = 0.006 < 0.05), there was no significant difference in logistic regression analysis (P = 0.161 > 0.05). The incidence of urethrocutaneous fistula was lower in TPIT-related operation than in TPIT-nonrelated operation (B = - 2.507, P = 0.000). The incidence of postoperative urethral diverticulum was lower in staged operation than in primary operation (B = - 1.737, P = 0.015).

Conclusion: For patients with disorder of sex development undergoing urethroplasty, the length of urethral defect is an independent risk factor affecting both the success rate of operation and the urethrocutaneous fistula. The age of the first operation has a statistically significant effect on the occurrence of postoperative urethrocutaneous fistula, but it is not an independent factor. Urethrocutaneous fistula is less found in TPIT-related operation in the study. Staged operation is an independent protective factor for postoperative urethral diverticulum compared with one-stage operation but isn't related to urethrocutaneous fistula.

Keywords: Analysis; Disorders of sex development; Influencing factors; Urethroplasty.

Fig. 1

TPIT operation a Preoperation appearance; b Dorsal plication was performed to completely correct severe chordee; c rectangular flap was harvested from the inner prepuce and the mobilized foreskin was rolled into a tube over a catheter. d The neourethra was anastomosed with the native urethra and the distal meatus was attached to the top of the glans with interrupted fine sutures; e The neourethra was covered by flap

Fig. 2

Koyanagi operation a preoperative appearance; b Penile degloving; c, d The dorsal median longitudinal cut of the foreskin is indicated and transferred ventrally;e–i Urethroplasty, first by closing the medial e, f and then the lateral edges of the wing flaps over the inlying urethral catheter (g, h, i); j the neourethra was covered by flap

Fig. 3

Byars staging operation a preoperative appearance; b Degloving and chordee release; c, d Preputial skin flap (Byar’s flap) sutured to cover the raw area created on retraction of the “glans wings” and on areas created after release of chordee. e Preoperative appearance of 2nd staged operation; f Parallel lines were marked on the ventral side of the penis according to the catheter circumference and urethra defect. g The rotated skin was tubularized around the catheter to make the new urethra. h The neourethra was covered by flap

Fig. 4

Staging TPIT operation a preoperation appearance. b Rectangular flap was harvested from the inner prepuce and the mobilized foreskin was rolled into a tube over a catheter; c The glans channel was created; d The proximal end of the new urethra was anastomosed with the posterior wall of the external urethra, using the anterior wall to form fistula; e Preoperation appearance of the second stage; f, g Urethral fistula was repaired in the second stage; h The neourethra was covered by flap

Fig. 5

The success rate of operation and the basic situation of postoperative complications. Among the 110 cases of DSD, 62% belonged to successful operation, 38% had complications in which 19% urethrocutaneous fistula, 13% urethral diverticulum, and 6% urethral stricture

Fig. 6

The correlation analysis between the risk factors and the effect of operation. The success rate of operation was relative to the length of urethral defect (P = 0.005 < 0.05). Urethrocutaneous fistula was related to the age of first operation (P = 0.006 < 0.05), the length of urethral defect (P = 0.005 < 0.05)

Fig. 7

Relationship of the age of first operation (AFO) and the length of urethral fistula. The age of first operation (AFO) and the length of urethral fistula are related (P = 0.000 < 0.05)