[size=20px]A pediatrician sees an otherwise well six-week old former term baby for drainage from the umbilicus. On exam there is an eight mm diameter mound of pink tissue with no active drainage. He prescribes silver nitrate for the lesion, orders an ultrasound and refers the baby to see a pediatric surgeon. After silver nitrate application the lesion has regressed and only a scab remains. There has been no drainage for a week. The ultrasound reveals a three to six mm hypoechoic tract extending from the bladder to the umbilicus. The abdominal exam is normal except for the scab at the umbilicus. There is no sinus tract.

 

The best next step in management for this asymptomatic baby with a history of umbilical drainage is

 

A observation with clinic follow-up.

 

B application of antibiotic ointment.

 

C further application of silver nitrate.

 

D resection of a urachal remnant.

 

E voiding cystourethrogram.[/size]

A

(Untitled)

 

a

correct answer

A observation with clinic follow-up.

 

The urachus is a tubular structure that connects the embryo to the allantois. Later in development the urachus goes from the dome of the fetal bladder in the preperitoneal space of the abdominal wall and out the umbilical cord. It normally obliterates during the later half of gestation and the fibrous remnant is identifiable as the median umbilical ligament. The obliterative process may be delayed until after birth but is usually complete in the first year of life. When the obliterative process is incomplete there are four types of persistent urachal remnants

• a cyst (the most common anomaly)
  
• a bladder diverticulum
  
• a urachal sinus
  
• a patent urachus
  

Many children with umbilical granulation tissue and drainage are referred to pediatric surgeons but few have urachal or omphalomesenteric remnants. Ultrasound in these newborns sometimes demonstrates a questionable urachal sinus tract or cyst. The patient described had an umbilical granuloma that was successfully treated with silver nitrate and an incidental urachal remnant that could be involuting.

 

Because urachal remnants are often discovered incidentally, remain clinically silent and may spontaneously involute, the trend has been to recommend nonoperative management for asymptomatic remnants. In the absence of symptoms in a newborn, a period of observation with a repeat ultrasound is a reasonable approach. Some advocate for nonoperative management of even symptomatic remnants, although the risks of recurrent infection and rare malignant degeneration later in life are not completely defined.

 

Antibiotic ointment and silver nitrate won’t have any effect on urachal epithelium and the description is of a dry, nearly closed wound so they won’t further healing. A voiding cystourethrogram is not necessary since the incidence of unsuspected lower urinary tract abnormalities in patients with urachal anomalies is quite small and the test is unlikely to identify a remnant tract.

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