There are a number of lesions that occur at or near the umbilicus during childhood, especially during infancy. Their natural history and management are dependent on clinical diagnosis.
By Dr Michael Collin, Paediatric Surgeon, Subiaco & Joondalup
Persistent paediatric umbilical hernias are caused by the failure of the umbilical cicatrix to scar down and close through early childhood, leaving a defect in the abdominal musculature that allows intra-abdominal contents to protrude through the defect into a sac under the umbilicus.
The normal natural history of the umbilicus after delivery involves the Wharton’s jelly surrounding the vessels becoming scarified and the navel formed by the remnant umbilical cord stump.
Beneath the umbilicus, the cicatrix is formed as the small umbilical ring closes and scars down. This process can continue to occur through the first few years of life.
While all babies are born with the umbilical defect, at least 20% will persist clinically through the first year of life, some even getting larger initially. Although 98% will resolve by 3-4 years of age.
Umbilical hernias that persist beyond this period could be considered for repair. Complications are exceptionally rare, with entrapped omental or pre-peritoneal fat much more common than bowel incarceration.
Umbilical hernias may be symptomatic, most commonly with pain, and may also cause issues in adulthood. Families may elect to observe uncomplicated, asymptomatic umbilical hernias. Repair, if offered, usually involves an infraumbilical incision and primary closure of the defect. Unlike adults, use of mesh in the paediatric population is exceptionally rare.
Supraumbilical hernias
While an umbilical hernia is most likely to resolve, a supraumbilical hernia is unlikely to do so. Unlike umbilical hernias, which have a concentric swelling of the umbilicus, a supraumbilical hernia can be identified by the bulge creating a more prominent infraumbilical crease with a flattened appearance superiorly (see Figure 2).
To achieve a good cosmetic result, an infraumbilical incision and separation of the cicatrix to access the hernia, with subsequent umbilicoplasty (reconstruction) is preferred.
Epigastric hernias
Epigastric hernias are defects in the linea alba (midline fascia between the recti) that occur in the line between the xiphisternum and the umbilicus. They are often small and most commonly contain pre-peritoneal fat from the falciform ligament.
They may be symptomatic even if small. Repair is achieved easily through a small incision over the defect.
A common differential is divarication of the rectus musculature, which occurs with a laxity of the linea alba that causes swelling all the way from the xiphisternum through to the umbilicus, with the muscle edges visible laterally to the bulge.
There is no actual defect in the linea alba and as the child grows the bulge/divarication should become less pronounced or resolve completely. There is no role for surgical correction of divarication.
Other umbilical lumps
Small umbilical granulomas or polyps can form as a result of granulation tissue forming in the umbilicus after Wharton’s jelly fails to completely scarify. In a general practice setting, a small flat granuloma can be safely managed with cauterisation with silver nitrate sticks, with or without paraffin around the lesion on the normal skin to protect it.
A more polypoid lesion, especially with a narrow base, can be managed with a simple suture ligation. Place a suture tie with double throw or slip knot at the base of the lesion and tighten to ensnare and strangulate the polyp. The lesion should become ischemic and auto-amputate within a week. A failure of outpatient-based management may require surgical excision.
The differential for these granulomas includes lesions related to a persistent vitello intestinal duct or urachus, or a distinct remnant of these. These structures are embryological remnants of the foetal yolk sac and allantois.
Beware of a cherry red appearance of mucosa, discharge from the umbilicus – especially if chyme/faeculant or urinary in nature – or any clearly patent lumen. A true remnant of these structures will require formal surgical excision.
A cystic lesion within the umbilicus and covered with skin may be a simple epidermoid cyst, although these will also likely benefit from formal excision.
Key messages
- Most babies are born with a small umbilical defect that closes in 98% of cases in the first few years, even if it appears to get larger in the first few months.
- Lesions that are unlikely to resolve include supraumbilical or epigastric defects or remnant embryological structures, persistent polyps and cysts.
- While the risk of complications from these lesions is small, they can be symptomatic and require formal surgical management.
Author competing interests- nil
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