Congenital urethral diverticulum with a large stone in a 16-year-old male: a case report

Abstract

Background

Urethral diverticulum is a sac-like dilation that extends from the urethral lumen and is connected to it. It can either be congenital or acquired, with the latter being more common. The development of calculi is rare in such patients. Management is tailored based on the patient’s symptoms and findings from investigations.

Case presentation

A 16-year-old African male presented with recurrent urinary tract infections and a burning sensation during urination. He was diagnosed with a congenital Urethral diverticulum in the bulbar urethral containing a large stone based on the findings of echography and retrograde urethrogram. He underwent urethral diverticulectomy and stone removal, and was discharged without any complications.

Conclusion

This case illustrated the uncommon presentation of congenital Urethral diverticulum with a large calculus. The cause of congenital urethral diverticula is unknown, with multiple theories proposed. The reason behind the development of such a large stone is most likely due to insufficient medical services and delayed diagnosis in the patient’s environment.

Background

Urethral diverticulum (UD) is a sac-like dilation that extends from the urethral lumen and is connected to it [1, 2]. UD is classified into congenital and acquired types in males, with 90% being acquired and 10% may be congenital [2, 3]. Diagnosis of male congenital diverticulum is common at an average age of 13 years [4]. Urethra is an uncommon site for urolithiasis in the lower urinary tract, with only 0.3% of patients experiencing urinary calculi in this region [2]. Few articles discuss large stone in male congenital UD. Here, we describe a case of a 16-year-old African male with a congenital UD located on the ventral aspect of the bulbar urethral, along with a large stone.

Case presentation

A 16-year-old African male presented to the urology department with recurrent urinary tract infections and a burning sensation during urination. His medical history was unremarkable. Vital signs showed fever, while the others were within normal range. Physical examination revealed pus-like discharge from the urethral and swelling on the ventral of the bulbar urethral, which was rigid, well-defined, and non-compressible. Complete Blood Count (CBC) were within normal range. Urinalysis showed the presence of blood in the urine (hematuria) and pus (pyuria). Echography was performed, revealing a large stone with acoustic shadowing in the ventral aspect of the bulbar urethral. Retrograde urethrogram (RUG) illustrated a large, well-defined, and round cystic lesion on the ventral aspect of the bulbar urethral (Fig. 1). Following this examination, the patient was diagnosed with a congenital UD, attributed to the absence of a history of urethral surgery or trauma. Under general anesthesia, the patient underwent urethral diverticulectomy. An incision was made on the ventral bulbar penis, followed by the dissection of the skin and corpus spongiosum. When the diverticulum became visible, its wall was dissected from the urethral, the stone (which is believed to be of calcium oxalate origin, given its rigid nature) was removed, and a diverticulectomy was performed (Fig. 2). Subsequently, urethral anastomosis was conducted, and a Buck’s fascia was placed. After that, the corpus spongiosum and skin were sutured. A Foley catheter was inserted after the surgery, and after 10 days, no complications were reported—the foley catheter was removed and the patient was discharged in good health.

Fig. 1

Retrograde urethrogram revealed a large, well-defined, and round cystic lesion on the ventral aspect of the bulbar urethral

Fig. 2

Intraoperative view. (A): observation of diverticulum and stone. (B): Stone removal and diverticulectomy procedure. (C): Measurement of the removed stone

Discussion

The etiopathogenesis of congenital primary diverticulum has been attributed to several theories. One theory suggests that it may result due to defective closing of the bulbous portion of the urethra due to the partial lack of spongiosum tissue. It often occurs at the ventral aspect of the anterior urethra. Another perspective indicates that UD mostly occurs in the expansion of the cystic duct, Cowper’s gland, or other urethral gland cystic [5]. Clinically, patients with UD may present with a range of symptoms, including urinary infections, hematuria, dysuria, weak urine stream, dribbling of urine, and urinary tract obstruction [4, 5]. The development of calculi is observed in 4–10% of patients with UD, although cases involving massive stones are exceedingly rare [6, 7]. Diagnosis typically based on a detailed medical history and various imaging modalities such as retrograde urography (RUG), intravenous urography (IVU), magnetic resonance imaging (MRI), and urethroscopy. Micturating cystourethrography is central to establishing the diagnosis [4]. In this case, RUG played a crucial role in identifying the diverticulum. Management strategies for UD are tailored based on the patient’s symptoms and findings from investigations. Asymptomatic uncomplicated UD may be managed conservatively with regular follow-up, while symptomatic or complicated cases often need surgical intervention. Surgical options typically involve excision of the diverticulum and reconstruction of the urethra, aiming to preserve its patency and continuity. Urethral diverticulectomy combined with urethral reconstruction is regarded as the standard treatment approach [3].

Conclusion

This case illustrated the uncommon presentation of a congenital UD with a large stone. While the development of calculi within diverticula is documented, occurring in 4–10% of cases, the presence of a large stone is exceedingly rare.The large stone likely formed due to urine stagnation within the diverticulum. The lack of a history of urethral trauma or surgery in this patient supports the congenital origin of the diverticulum. The exact etiology of congenital urethral diverticula remains unclear, with several theories proposed, thus further research is essential to enhance understanding and management of these conditions.