What is urachus and why does it not overgrow?
During the prenatal period, fetal urine partially flows through the urachus to the umbilical cord. By the third trimester, the duct collapses and becomes obliterated. The exact reason why it remains patent in some people is unknown: it is believed that disruption of the normal descent of the bladder into the pelvis plays a role. In newborns, the anomaly is noticed due to a weeping navel, and in adults it often proceeds hidden for years and first manifests itself as inflammation. Men experience symptomatic urachal cysts much more often than women.
- Urachus - embryonic urinary duct
- Normally turns into the median umbilical ligament
- The anomaly is rare and is congenital
- In adults, it is often detected incidentally
- Suppuration is the most common reason for treatment
Types of urachus cleft
The shape of the anomaly depends on which part of the duct remains open. Complaints also depend on this: with a complete fistula, urine leaks directly from the navel, with a cyst, a closed cavity is formed in the thickness of the abdominal wall, and with a diverticulum, the connection remains only with the bladder and is in no way noticeable from the outside. Ultrasound and contrast studies help differentiate between options, and this is important for planning surgery.
- Complete patent urachus (vesico-umbilical fistula) - leakage of urine from the navel
- Urachal cyst - a closed cavity in the middle part of the duct
- Umbilical sinus - blind tract open to the outside
- Bladder diverticulum - open part at the top of the bladder
- Mixed and incomplete forms
Symptoms
An uncomplicated cyst usually does not cause any concern. When an infection occurs, a dense, painful formation appears in the midline of the abdomen below the navel, the skin above it turns red and becomes hot. The temperature rises and discomfort may occur when urinating. If the abscess opens out, cloudy contents begin to be released from the navel, and it becomes easier for a while - but after a few weeks or months the inflammation usually returns.
- Weeping navel and urine-smelling discharge
- Painful lump between the navel and pubis
- Redness of the skin around the navel
- Fever, weakness
- Frequent or painful urination
- Recurrent episodes of navel inflammation
Diagnostics
The first step is an ultrasound of the bladder and anterior abdominal wall: the method is accessible, safe for children and clearly shows the cavity or cord between the navel and the top of the bladder. To clarify the boundaries of the formation and plan the operation, MSCT or MRI with contrast is used. In case of an external fistula, fistulography is performed; if a connection with a bladder is suspected, cystoscopy is performed. In older adults, the doctor additionally excludes a rare tumor of the urachus, so the removed tissue must be sent for histological examination.
- Ultrasound of the bladder and anterior abdominal wall
- Ultrasound of soft tissues of the periumbilical region
- MSCT or MRI of the abdomen and pelvis
- Fistulography for external fistula
- Cystoscopy
- General urine analysis and culture of discharge
- Histological examination of removed tissues
Treatment and observation
In case of acute suppuration, the inflammation is first relieved: antibiotics are prescribed, and if an abscess is formed, drainage is performed. A radical solution is complete excision of the remnants of the urachus along with the adjacent part of the apex of the bladder; the operation is performed by open or laparoscopic access as planned, after the inflammation has subsided. If we limit ourselves only to opening the abscess, the inflammation, as a rule, recurs. In infants, small asymptomatic anomalies are sometimes observed: some of the ducts mature and close in the first year of life. The decision on the timing of the operation is made by the surgeon.
- Antibacterial therapy for inflammation - as prescribed by a doctor
- Abscess drainage at the first stage
- Planned complete excision of the urachus
- Laparoscopic approach with suitable anatomy
- Observation in children of the first year with asymptomatic forms
- Control ultrasound after treatment
