The abdominal wall and inguinoscrotal conditions
Spencer W. Beasley, John Hutson, Mark Stringer, Sebastian K. King, Warwick J. Teague in Paediatric Surgical Diagnosis, 2018
Before birth, the umbilical ring is a normal opening in the ventral abdominal wall at the site of attachment of the umbilical cord to the fetus. Early in development, the midgut communicates with the yolk sac via the vitelline duct (yolk stalk) but this normally involutes by birth. Persistence of part or all of the vitelline duct produces a variety of conditions, including Meckel diverticulum, ectopic mucosa at the umbilicus and patency of the vitello-intestinal duct. The urachus connects the bladder to the allantois in the umbilical cord. Failure of the urachus to obliterate results in urinary discharge from the umbilicus or a urachal sinus or cyst. At the time of birth, the main structures passing through the umbilical ring are the two umbilical arteries and the umbilical vein. After birth, the umbilical stump desiccates and separates from the umbilicus, leaving a dry corrugated dimple. Failure of contraction of the umbilical ring in the first few weeks after birth may lead to an umbilical hernia, in which peritoneum protrudes into the skin-covered defect. Some degree of umbilical herniation is present in about 20% of newborn babies, and is even more common in the premature. When the infant lies quietly, the umbilical skin looks redundant, but on crying or straining, bowel fills the hernia, giving the umbilicus a tense and slightly blue appearance beneath the shiny skin; however, it is non-tender and reduces easily. The vast majority of umbilical hernias close spontaneously in the first few years of life. The skin overlying the hernia never ruptures and strangulation of the contents is exceptionally rare.
Bladder cancer
Anju Sahdev, Sarah J. Vinnicombe in Husband & Reznek's Imaging in Oncology, 2020
Primary bladder adenocarcinoma accounts for around 2% of bladder cancers. These lesions may be primary or secondary, non-urachal or urachal. Urachal adenocarcinoma is associated with a persistent urachus or more severe congenital anomalies such as bladder exstrophy. Urothelial metaplasia from chronic irritation, urinary diversions, and pelvic lipomatosis are also risk factors, and around 25% of patients with urachal adenocarcinomas will have some mucus in the urine. The imaging characteristics of a urachal adenocarcinoma are typically a large mixed solid and cystic lesion (Figure 16.27), and approximately 70% of lesions demonstrate some calcification, which is usually around the edge of the tumour and is patchy rather than continuous unlike the surface calcification in SCC. Mucin secretion in these tumours results in a high signal on T2W MRI. They commonly arise at the dome of the bladder and along the course of the urachus, and the bulk of the tumour may be outside the bladder. Extravesical spread and peritoneal metastases are common (12,69).
Neonatal and General paediatric Surgery
Stephan Strobel, Lewis Spitz, Stephen D. Marks in Great Ormond Street Handbook of Paediatrics, 2019
A number of defects can occur at the umbilicus. Each requires precise diagnosis as their treatment differs considerably: Umbilical granuloma: due to failure of the umbilical cord to separate completely. Application of silver nitrate to the granulation tissue will result in its resolution (Fig. 18.42).Umbilical polyp: due to persistence of a remnant of the vitello-intestinal duct at the umbilicus. It is covered by mucosa that requires formal excision (Fig. 18.43).Patent vitello-intestinal duct. There is a fistula at the umbilicus through which intestinal content is evacuated. There is a distinct risk of prolapse of the intestine through the fistula or volvulus around the ‘band’. Urgent surgery is required to excise the fistula from the umbilicus to the ileum and restore intestinal continuity by end-to-end anastomosis (Fig. 18.44).Patent urachus. This is a communication between the bladder dome and the umbilicus that may produce a persistent urinary leak. It is important to exclude a bladder outlet obstruction (e.g. posterior urethral valves) before attempting closure of the urachal remnant (Fig. 18.45).
Villous adenoma of the urethra
Published in Baylor University Medical Center Proceedings, 2021
Katherine E. Dowd, Derek Yang, Harry Papaconstantinou, Erin T. Bird
Villous adenoma is commonly encountered in the colorectal practice but is rarely seen by the urologic surgeon. Fibroepithelial urethral polyps are more readily seen by the urologist; they are generally benign and can be treated with local resection/ablation to resolve irritative voiding symptoms. Other encountered benign urethral lesions include hemangiomas, leiomyomas, urethral diverticulum, and cowpers gland or skenes gland duct cysts. Due to the variability of presentation of suspicious lesions, most urologists opt for biopsy at the time of resection or fulguration to rule out underlying malignancy. Villous adenomas of the genitourinary tract have been reported, but generally in small case series or reviews of case reports.1 They present similarly to other urethral lesions—with gross hematuria, dysuria, or irritative voiding symptoms—and a histopathologic diagnosis is usually needed.1 Because reports of association with adenocarcinoma exist, most authors recommend full resection of the lesion and consideration of magnetic resonance imaging (MRI) and colonoscopy to rule out coexisting adenocarcinoma or malignancy.2 The tumor is more commonly encountered at the bladder dome, trigone, and urachus if present.3
Prenatal Detection of Vesico-Allantoic Cyst: Ultrasound and Autopsy Findings
Published in Fetal and Pediatric Pathology, 2023
Maria Paola Bonasoni, Giuseppina Comitini, Ottavia Cavicchioni, Veronica Barbieri, Giulia Dalla Dea, Andrea Palicelli, Lorenzo Aguzzoli
At early embryonic development, the fetal bladder communicates with the allantois, which later regresses into a fibrous remnant: the urachus. If the urachus remains patent, the communication between the allantois and the fetal bladder persists, resulting in the vesico-allantoic cyst. At prenatal ultrasound (US), it appears as a hypoechogenic dumb-bell shaped structure [1,2]. A patent urachus is observed more frequently in males and the frequency is reported around 3 for 1,000,000 live births [1]. The outcome of vesico-allantoic is variable, the cyst may persist until birth, regress during pregnancy or even rupture into the umbilical cord [3,4].
A painful periumbilical rash
Published in Baylor University Medical Center Proceedings, 2019
Sima Amin, Sheevam Shah, J. Scott Thomas, Katherine Fiala
The umbilicus was surgically explored to rule out a persistent urachus and revealed a 7-cm defect that tunneled down to the fascia. The wound was irrigated with povidone-iodine solution and packed with iodoform gauze. After surgery, she was treated with wound care and a 1-month course of amoxicillin for the actinomyces grown on wound culture broth. The drainage and erosive lesions initially improved; however, 10 months later, the patient is considering magnetic resonance imaging to further evaluate the soft tissue defect and umbilical excision.
Related Knowledge Centers
- Allantois
- Bladder
- Fetus
- Mesonephric Duct
- Peritoneum
- Umbilical Cord
- Urogenital Sinus
- Retropubic Space
- Transversalis Fascia
- Renal Calyx