What is the urachus? The urachus is a remnant of a...

What is the urachus?

The urachus is a remnant of a channel between the bladder and the umbilicus (belly button) where urine initially drains in the fetus during the 1st trimester of pregnancy. The channel of the urachus usually seals off and obliterates around the 12th week of gestation and all that is left is a small fibrous cord between the bladder and umbilicus called the median umbilical ligament. 

What are the disorders of the urachus and the symptoms? 

Disorders of the urachus occur when there are abnormalities with the sealing off of the channel during fetal development.  There are at least 4 types of urachal abnormalities seen .

 Types of urachal anomalies

 This occurs when a section of the urachus did not seal off, but there is not a connection between the bladder and umbilicus.  Often, this is asymptomatic and is only detected when an ultrasound is performed for other reasons.  Occasionally urachal cysts can become infected and could cause abdominal pain or could start to leak cloudy or bloody fluid at the umbilicus.  The average age for urachal cysts to present with an infection is 2-4 years old. 

Patent urachus

This occurs when the urachus did not seal off and there is a connection between the bladder and the umbilicus.  A patent urachus can cause varying amounts of clear urine to leak at the umbilicus. 

Urachal sinus

This occurs when the urachus did not seal close to the umbilicus and leads to a blind ending tract from the umbilicus into the urachus called a sinus.  These can be asymptomatic or present with infection with abdominal pain and drainage of fluid. 

Diverticulum

This occurs when the urachus did not seal close to the bladder and leads to a blind ending tract from the bladder into the urachus called a diverticulum.  These also can be asymptomatic or present with a urinary tract infection. 

How are the urachal disorders diagnosed?

Urachal disorders are usually diagnosed when there are symptoms such as: drainage from the umbilicus, redness around umbilicus, abdominal pain, or urinary tract infection.  An ultrasound can often detect urachal anomalies but occasionally other tests are needed.  A sinogram or sinography is a test where contrast is injected into the umbilicus to see if there is a patent urachus or urachal sinus.  Another test called a VCUG (see voiding cystourethrogram) is also occasionally performed if there is a urinary tract infection or to ensure that the bladder drains properly.  Rarely tests such as a CT scan or MRI are needed for diagnosis. 

How are the urachal disorders treated?

If the urachal disorder presents with an infection, the infection is treated first.  This requires antibiotics, possible admission for intravenous antibiotics, and occasional surgical drainage of any infected cyst or poorly draining cavity.  Once the infection is under control, excision of the urachus is usually performed.  This can usually be done laparoscopically or with a small incision on the lower abdomen.  Patients usually stay in the hospital 1-2 days after the surgery.  The urachus can be excised because in normal development it usually obliterates anyway.  The umbilicus is not removed. 

What happens after treatment?

After control of any infection and surgical removal of the urachal abnormality, your child can be expected to not have any more problems with the urachus.  There is a small risk of localized infection (< 10%) after removal of the urachus, but this can usually be treated with just antibiotics. 

Patent Urachus Repair

Description

Children who have this surgery will have general anesthesia (asleep and pain-free).

The surgeon will make a cut in the child's lower belly. Next, the surgeon will find the urachal tube and remove it. The bladder opening will be repaired, and the cut will be closed.

The surgery can also be done with a laparoscope. This is an instrument that has a tiny camera and light on the end.

• The surgeon will make 3 small surgical cuts in the child's belly. The surgeon will insert the laparoscope through one of these cuts and other tools through the other cuts.

• The surgeon uses the tools to remove the urachal tube and close off the bladder and area where the tube connects to the umbilicus (belly button).

This surgery can be done in children as young as 6 months.

Before the Procedure

The surgeon may ask your child to have:

• A complete medical history and physical exam.

• Kidney ultrasound.

• Sinogram of the urachus. In this procedure, a radio-opaque dye called contrast is injected into the urachal opening and x-rays are taken.

• Ultrasound of the urachus.

• VCUG (voiding cystourethrogram), a special x-ray to make sure the bladder is working.

• CT scan or MRI.

Always tell your child's health care provider:

• What drugs your child is taking. Include drugs, herbs, vitamins, or any other supplements you bought without a prescription.

• About any allergies your child may have to medicine, latex, tape, or skin cleaner.

During the days before the surgery:

• About 10 days before the surgery, you may be asked to stop giving your child aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve, Naprosyn), warfarin (Coumadin), and any other drugs that make it hard for blood to clot.

• Ask which drugs your child should still take on the day of the surgery.

On the day of the surgery:

• Your child will probably not be able to drink or eat anything for 4 to 8 hours before surgery.

• Give your child any drugs you have been told your child should have with a small sip of water.

• Your child's provider will tell you when to arrive at the hospital.

• The provider will make sure your child has no signs of illness before surgery. If your child is ill, the surgery may be delayed.

After the Procedure

Most children stay in the hospital for just a few days after this surgery. Most recover rapidly. Children can eat their normal foods once they start eating again.

Before leaving the hospital, you will learn how to care for the wound or wounds. If Steri-Strips were used to close the wound, they should be left in place until they fall off on their own in about a week.

You may get a prescription for antibiotics to prevent infection and for a safe medicine to use for pain.

Outlook (Prognosis)

The outcome is most often excellent