Continuing Education Activity

Epispadias is a rare urogenital anomaly characterized by the failure of the urethral tube to tubularize on the dorsal aspect. Although commonly associated as a part of bladder exstrophy-epispadias-complex (BEEC), isolated epispadias occurs less frequently. Its diagnosis is clinical and does not require any additional investigations. The most important factor determining postoperative continence in these patients is the availability of a skilled pediatric surgeon/urologist. This activity outlines the etiology, pathogenesis, and surgical management of epispadias and highlights the role of the interprofessional team in the care of patients with this condition.

Objectives:

• Outline the etiology of epispadias.

• Describe the appropriate evaluation of epispadias.

• Review the common approaches of surgical management of epispadias in males and females.

• Summarize the interprofessional team strategies for improving care coordination and communication, leading to superior outcomes of children with epispadias.

Introduction

Epispadias is a rare urogenital malformation characterized by the failure of the urethral tube to tubularize on the dorsal aspect. Unlike in hypospadias, where the meatus is on the ventral aspect, children with epispadias have a wide-open urethral plate on the dorsum. It is commonly seen as a component in the spectrum of bladder exstrophy-epispadias-complex (BEEC). Isolated epispadias constitutes less than 10 percent of the total cases of epispadias.[1] Isolated male epispadias is rare, with an incidence of less than 1 per 100,000 live births.[2] 

Males have characteristic anatomic abnormalities, including a short-stubby phallus with a dorsally located meatus, upward-pointing phallus, and ventral hooding of the prepuce. Female epispadias is even rarer with an incidence ranging from at least 1 in 160,000 to 1 in 480,000 live births.[3] Girls have a bifid clitoris, patulous urethral opening, anteriorly placed vaginal opening, and ill-formed or absent mons. Pubic diastasis is seen in both males and females with epispadias. Varying degrees of urinary continence are reported in these patients, and depending on the degree of continence, they can be categorized into continent or incontinent epispadias. The diagnosis of epispadias is clinical and does not require any additional investigations. The most important factor determining postoperative continence in these patients is the availability of a skilled pediatric surgeon/urologist. Long-term follow-up is necessary to address the psychosexual issues during the transition from childhood to adolescence and adulthood.

Etiology

Epispadias lies on the milder end of the spectrum of anomalies under the bladder exstrophy-epispadias-complex (BEEC). Although a number of theories have been put forward for its occurrence, whether as a part of BEEC or isolated, the exact cause of epispadias is still unclear. It is believed that abnormalities of the cloacal membrane might be responsible for its occurrence. An abnormally large cloacal membrane not only prevents the normal migration of mesenchymal tissue but is also prone to early rupture, leading to this spectrum of anomalies. Isolated epispadias occurs when this rupture causes a non-union of the distal portion of the urinary tract.[4] Various animal models have also suggested that interactions between growth factors and transcription factors might play a role in its occurrence.[5]

Epidemiology

Epispadias is a rare congenital birth defect with an estimated prevalence of 1 in 10,000 to 50,000. The disease is more common in males than in females. The incidence of isolated male epispadias is 1 in 100,000. In females, it is even rarer, with an incidence ranging from 1 in 160,000 to 1 in 480,000.[2][3] The risk factors for epispadias are similar to that of other forms of BEEC. No additional risk factors for epispadias are known. While compliance with periconceptional folate reduces the risk of severe forms of the spectrum of BEEC, the risk of occurrence of milder forms like isolated epispadias is not decreased.[2][6]

Pathophysiology

Isolated male epispadias is characterized by a short phallus, an abnormal dorsally located urethral meatus, dorsal chordee, and a ventrally hooded prepuce. Depending on the position of the meatus, male epispadias is categorized into glandular, penile, and penopubic forms. Urinary incontinence is almost always seen in the penopubic forms due to the incompetent bladder neck. Until recently, it was believed that the degree of incontinence depends only on the position of the meatus, with distal (glandular) epispadias not having incontinence issues. Histological abnormalities in the roof of the urethra have shown that there are additional factors contributing to the development of continence in these patients.[7] 

Similar to male epispadias, female epispadias can be categorized into vestibular, sub-symphyseal, and retro-symphyseal types. Only a patulous urethral meatus is seen in the vestibular forms. However, the retro-symphyseal form can present with complete incontinence and extremely small bladder capacity.[8]

History and Physical

When presenting as a component of the severe forms of the BEEC, the diagnosis is usually apparent at birth and does not require additional investigations. Similarly, the majority of newborns with isolated male epispadias can be diagnosed by the pediatrician or neonatologist involved in immediate post-natal care. However, glandular epispadias and female epispadias are difficult to diagnose and require careful identification of the external genitalia. In the former, the diagnosis can be missed if the child is continent, and is usually identified at the time of circumcision when the foreskin is retracted. Female epispadias also poses a diagnostic challenge to the pediatric surgeon because of the rarity of the disease and are often noticed only on precise perineal examination when the toilet training is delayed.[9] 

Urinary incontinence in isolated epispadias needs a special mention. In males, it is variable and was earlier believed to depend only on the position of the meatus, with the majority of the penopubic defects being incontinent due to invariable involvement of the bladder neck in these cases. However, recent reports mentioning total incontinence in distal epispadias have initiated discussions regarding other factors also contributing to the continence mechanism in these cases. In females, the continence mechanism is invariably involved, and incontinence is a usual symptom.[9][10] On examination of the external genitalia, the following characteristic features are found in isolated epispadias:

Males: Short and stubby phallus with dorsal meatus, dorsal chordee, and ventrally hooded prepuce are classical features on examination. Splaying and shortening of the corpora is another feature universally found in male epispadias. Splaying is seen due to pubic diastasis. The total corporal length is short due to the foreshortened anterior corporal segment (the posterior segment is normal). Other factors contributing to the smaller appearance of the phallus include the short urethral plate and dorsal chordee. All of these have to be addressed during epispadias repair for penile lengthening. The vas and ejaculatory ducts are normal in these children but have a risk of getting injured during the reconstructive procedure.[10] 

Females: Bifid clitoris, anteriorly placed vaginal orifice, absent mons, and patulous urethral orifice with visible bladder neck are classical features on perineal examination of girls with an epispadias.[10] Apart from these, when associated as a part of BEEC, other clinical features are also present. However, a detailed discussion about all the features of BEEC is beyond the scope of this article.

Evaluation

Similar to exstrophy bladder, the diagnosis of epispadias is clinical and does not require any other additional investigations for diagnosis. A plain radiograph should always be performed to document pubic diastasis. In children with incontinent epispadias, the bladder is a low-pressure receptacle. Thus, an ultrasound KUB to rule out associated congenital anomalies of the upper tract is usually sufficient in the preoperative period. Other investigations, including cystourethrography (MCUG) and nuclear scintigraphy scans, should be performed to assess the baseline renal function in children with continent epispadias, as tubularizing the open urethral plate will further increase the outlet resistance and may lead to upper tract damage. However, it has been shown that the incidence of vesicoureteric reflux before surgery ranges from 35% to 85%, due to lateral ureteral ectopia. Due to this, some surgeons perform MCUG and nuclear scintigraphy scans in all children.[9]

Treatment / Management

Surgical management of epispadias is challenging and requires technical expertise. The surgery aims to reconstruct the genitalia and urethra, providing optimal functional and cosmetic outcomes. At present, surgeons across the world have adopted either of the two following approaches. 

Modified Cantwell-Ransley repair: The initial procedure of mobilizing the urethral plate followed by tubularization and ventral movement between the corpora was described by Cantwell. Ransley changed the procedure to include mobilization of the urethral plate with separation of the corporal bodies, leaving the distal portion of the plate attached to the glans. Lateral glans wings are developed. A reverse-MAGPI (meatal advancement and granuloplasty) procedure is performed on the distal urethra. Cavernostomies are required to correct persistent chordee. The corporal bodies are medially rotated and reapproximated.[9][10] 

Complete penile disassembly technique (Mitchell and Bagli): The technique is based on the special anatomy in epispadias. According to the surgeons who first described it, the blood supply of the hemiglans is based on the dorsal complex on the lateral surface of the corpora. The corpora receive their blood supply from the central artery, and the urethral plate receives its supply from the proximal urethra. Therefore, the urethral plate can be completely lifted from the corpora and hemiglans, and both the corporal bodies can be separated from each other. This complete penile disassembly confers better reconstruction. Another advantage is that the dissection extends right to the bladder neck; therefore, a bladder neck repair (BNR) can be added in the same sitting.[10] Both techniques have their own merits and demerits, and the success of the reconstruction is based on the surgeon's expertise. 

Female Epispadias

Perineal approach: Although female epispadias is very rare, a few words must be mentioned about the reconstruction in females. The repair of epispadias in females follows similar surgical principles as in males. The urethra and bladder neck are mobilized along with the vagina. During mobilization of the urethra and bladder neck, the division of the intersymphyseal bands is crucial to ensure the completeness of the postero-lateral dissection. The exposure of the pelvic floor muscle complex marks the completion of posterior dissection. The mobilized urethra is then tubularized over a self-retaining catheter. The neourethra and the vagina are shifted posteriorly. The pubic bones are reapproximated and may require osteotomies for this. However, this is not universally performed by all surgeons. Subsequently, clitoroplasty and labioplasty are performed.[10]

Traditional staged approach: Due to the patulous bladder neck, the traditional approach for the management of female epispadias is urethroplasty, followed by bladder neck reconfiguration. Favorable continence results have been depicted when epispadias repair and bladder neck reconfiguration are performed successively at 12-18 months and 5-6 years of age respectively.[11]

Differential Diagnosis

Epispadias represents the mild form of the spectrum of anomalies included in BEEC. It must be differentiated from classical bladder exstrophy, in which the bladder plate is also exposed, apart from the open urethral plate, as seen in epispadias. The pubic diastasis is common among both bladder exstrophy and epispadias. Also, the most severe form of the spectrum is represented by cloacal exstrophy. It is characterized by the presence of major anomalies, including omphalocele, bladder exstrophy, imperforate anus, and spinal abnormalities. An isolated epispadias can easily be distinguished from these diseases on clinical examination. 

Hypospadias is another disease, which sounds similar, but has the exact opposite clinical features. Hypospadias has a ventral meatus, ventral chordee, dorsally hooded prepuce, and lacks pubic diastasis. Common urogenital sinus is frequently misdiagnosed as female epispadias, which is a disorder of sexual differentiation. The patulous urethral opening may appear to be a single opening in the vestibule. However, upon precise examination, the anteriorly placed vaginal opening becomes visible.

Prognosis

Urinary continence is an important issue in these children. Variable rates of continence, ranging from as low as 50% to up to 90%, have been mentioned by different centers across the world.[2][10] It depends on the type of epispadias in males, as an abnormal proximal urethra and incompetent bladder neck are almost always associated with penopubic defects. Similar to males, the continence rates after surgery for female epispadias are also variable. It ranges between 60%-80% in terms of daytime continence. However, achieving nocturnal continence is always an issue in these patients. Nocturnal continence rates hardly approach more than 50%.[8]

Complications

Apart from wound infection and dysuria (due to bladder spasms), some other surgical complications are possible when the surgery is not performed by an expert.[9][10] 

• Urethral stricture and obstruction: Improper tissue handling and vascular compromise can lead to the formation of strictures. These can be managed by dilatation, but occasionally require urethral substitution.
• Persistent chordee: This can be avoided by performing cavernostomies before medializing and re-approximating the corporal bodies.
• Persistent short length: Release of the corporal bodies, division of the intersymphyseal bands, and advancing the dissection till the bladder neck can increase the length.
• Urethral retraction and hypospadias: During complete penile disassembly, it not uncommon to have a deficiency of the urethral plate. In these scenarios, some surgeons resort to performing a distal preputial tube urethroplasty.
• Partial or complete penile loss: Although the supply of the hemiglans comes from the lateral surface of the corpora and is not based on the urethral plate, there are cases where penile loss has occurred postoperatively, even after careful dissection. This can be attributed to the rare vascular aberrations apart from the precarious blood supply in newborns.

Postoperative and Rehabilitation Care

Similar to bladder exstrophy, children undergoing epispadias repair require optimal postoperative care. The following elements must be taken care of during management of these children:

• Adequate pain relief: The surgery involves the repair of one of the most sensitive parts of the urinary tract i.e., bladder neck and urethra. Therefore, adequate postoperative analgesia is a must. Epidural analgesia in the initial postoperative period is followed by most of the centers across the globe. Intermittent pain can be relieved by using intravenous analgesics.
• Bladder spasms: As soon as the child is able to take orally, an anticholinergic medication should be started. These not only play a major role in detrusor relaxation but also have a local anesthetic action.
• Immobilization of the lower extremities: The immobilization of lower extremities is preferred when osteotomy is performed. However, performing the osteotomy is solely based on the surgeon's preference. Some surgeons emphasize on lower limb immobilization using a hip spica even when osteotomy is not performed. 
• Care of the indwelling catheter: Care of the bladder catheter cannot be emphasized more. It is always better to use a self-retaining catheter in these surgeries.

Consultations

Unlike bladder exstrophy, consultations with multiple specialties are seldom required in isolated epispadias. A trained pediatric surgeon/urologist has to be consulted immediately after birth, as an early repair will avoid an osteotomy. The involvement of a nephrologist in the care of these children might be required in occasional cases prone to upper tract damage and kidney injury. Adolescents with isolated epispadias may have psychosocial and sexual issues similar to those with patients of bladder exstrophy that need to be addressed properly. Therefore, consultation with a psychiatrist and a urologist/andrologist is required during their transitional care.

Deterrence and Patient Education

Epispadias lies on the milder end of the spectrum of anomalies in the BEEC complex. Therefore, the morbidity in these children is significantly less compared to those with classical bladder exstrophy and cloacal exstrophy. Although not having urinary continence majorly affects the quality of life, parents must realize that these children are completely healthy and achieve milestones according to their age. The continence rates after surgery are variable, ranging from 50%-85%. Better continence rates are noticed when the reconstruction is performed by skilled surgeons.[10] Thus, it is imperative for parents to consult a trained and experienced pediatric surgeon/urologist for reconstructive surgeries.

Enhancing Healthcare Team Outcomes

While a pediatric surgeon is involved in the surgical management of patients with epispadias, it is important to include an interprofessional team of specialists. The involvement of a nephrologist in the management of children who are prone to the upper tract damage (having anomalies of the upper urinary tract) is crucial. The nurses play an indispensable role in the interprofessional group. Educating the parents and patients about urinary habits, teaching exercises of the pelvic floor, ensuring proper hygiene, and ensuring compliance to medications are few roles of nurses apart from being involved in the crucial immediate post-operative care. 

The pharmacist also ensures that the child is on the right formulation and dosage of the antibiotics and anticholinergic medications. During the transitional care of these patients, the involvement of an andrologist/urologist and psychiatrist is often required to deal with the psychosexual issues. Thus, thorough planning and discussion with the members of the interprofessional group are needed to ensure optimal care and to improve the outcomes.[12] [Level 5]