Glandular diphallus with urethral duplication: Conventional technique for a rare congenital anomaly.

Diphallus is a rare anomaly and its association with urethral duplication is extremely rare. Numerous associated genitourinary and gastrointestinal anomalies have been reported with this condition. Challenges in the management are incorporation of the glans and the dominant urethra during reconstruction. We report the successful management of a case of glandular diphallus with complete urethral duplication retaining the dorsal urethra.

INTRODUCTION

Diphallus, or duplication of the penis (or clitoris), is a rare anomaly with an incidence of 1 in 5,500,000 live births.[1] Approximately 100 cases have been reported till 2009.[1] The extent of duplication varies greatly from a double glans arising from a common shaft to complete duplication of the phallus. It may be associated with other urogenital and anorectal malformations.[12345] Management includes assessment of the urethral anatomy and evaluation for the other associated anomalies. Surgical reconstruction must take into consideration the local anatomy to achieve good results.

CASE REPORT

A 1-year-old male child presented with straining and poor urinary stream along with abnormal appearance of the external genitalia noticed since early infancy. Clinical examination revealed duplication of glans in the sagittal plane; the dorsal glans was better in size than the ventral one and had a stenotic meatus at its tip, whereas the ventral glans was hyposplastic with its meatus at the coronal sulcus [Figures 1a and 2a]. The patient used to dribble from the dorsal meatus and had a thin stream from the ventral meatus. The penile length was good and there was no chordee. He also had pre-axial polydactyly in the left hand and deep first web space on the left foot.

Figure 1

(a) Pre-operative appearance – Yellow-colored arrow indicates dorsal glans. Blue-colored arrow indicates ventral hypoplastic glans. (b) Post-operative appearance. (c) Pre -operative MCUG-Effmann IIA2. Yellow arrow indicates dorsal urethra: Blue arrow indicates ventral urethra. Two urethral channels, a second (ventral) channel arising from the first channel and coursing independently through the meatus in the sagittal plane. (d) Post-operative MCUG

Further evaluation revealed solitary kidney and atrial septal defect which did not require any intervention. Urethral anatomy was delineated using ascending urethrography and micturating cystourethrography and the findings were suggestive of Effmann IIA2 duplication [Figure 1c] with a single, good capacity bladder without vesicoureteric reflux [Figures 1c and 2a]. The dorsal glandular size was good but had hypoplastic distal (2 cm) urethra which admitted only guide wire. The proximal dorsal urethra was of normal caliber. The ventral glans was hypoplastic and had a meatus at the corona with associated hypoplastic entire ventral urethra.

Figure 2

(a) Yellow arrow indicates proximal dorsal urethra of normal caliber. Blue arrow indicates ventral hypoplastic urethra and its glans. Shaded area indicates the area of excision. (b) Byars’ procedure stage 1 – Yellow arrow indicates distal laid open dorsal urethra. (c) Byars’ stage 2 repair. White arrow indicates reconstructed neourethra. (d) Cross-section of the neourethra – Ventral skin lined dorsal urethra. D – Dorsal, V – ventral, L – lumen

The patient underwent Byars’ staged genital reconstruction. In view of hypoplastic ventral glans with its associated narrow (hypoplastic) entire ventral urethra it was excised completely [Figure 2a]. The well-developed dorsal glans was preserved and its hypoplastic distal urethra was laid open and incorporated into the Byars’ flaps. Byars’ first stage urethroplasty [Figure 2b] consisted of penile degloving, creating and transferring Byars’ flaps ventrally and suturing to the edges of the laid open dorsal urethra. Subsequently patient underwent Byars’ second stage repair after 6 months [Figure 2c]. The post-operative period was uneventful and he had good functional and cosmetic outcome at 2.5 years of follow-up [Figure 1b and d].

DISCUSSION

The extent of duplication in diphallus varies from a double glans arising from a common shaft to complete duplication of the phallus.[4] Diphallus has been described in females with clitoral duplication.[2] Scheneider classified diphallus in three groups: Diphallus of glans alone, bifid diphallus and complete diphallus. Vilanova and Raventos have added a fourth category called pseudodiphallia.[2] The most widely followed classification for urethral duplication anomalies is described by Effmann et al.[12345]

Multiple embryological explanations for diphallus exist and have been summarized by Wilson and Hollowell.[345] Almost all authors agree that the anomaly is due to a defective fusion of the genital tubercle.[23] Johnson et al. classified the anomaly based on the number of corpus cavernosal bodies in each penis. True diphallia has two corpus cavernosal bodies; pseudodiphallia has a single corpus cavernosum in each penis.[4] In our case the glans was duplicated along with penile urethra but the corporal bodies were not duplicated.

There is no standard operative procedure for urethral duplication anomalies and most authors recommend excision of the non-dominant (dorsal) urethra[235] In our patient we have retained the dorsal urethra for reconstruction as it was of better caliber. To the best of our knowledge, retaining the dorsal urethra was unusual and has not been reported so far in the literature.

Passerini-Glazel et al. described the technique of PADUA (Progressive augmentation by dilating the urethra anterior) procedure for the treatment of severe urethral hypoplasia by using gradually progressive indwelling soft catheter or stent dilation.[5] This technique was not attempted in our patient as the patient required excision of the ventral hypoplastic glans. Mirshemirani et al. reported that treatment of diphallus usually includes excision of the duplicated penile structure and its urethra.[1] In our patient the ventral glans and its urethra were excised retaining the dorsal glans and its urethra for staged reconstruction.

The literature suggests that the best outcomes are seen using the ventral urethra for the reconstruction, but in our patient we have used the dorsal urethra for reconstruction with good results.

CONCLUSION

Management of glandular diphallus requires proper evaluation and tailoring the reconstruction to the individual patient anatomy. Good cosmesis and functional outcome can be achieved as demonstrated in our case.