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CHAPTER 57

Disorders of the Umbilicus

Jean Heuric Rakotomalala
Dan Poenaru
Ruth D. Mayforth

Introduction Table 57.1: Embryology and pathology of umbilical disorders.
Umbilical disorders are frequently encountered by paediatric surgeons. Embryological Normal remnant Pathological abnormality
In the newborn, the umbilical cord typically desiccates and separates element
within three weeks, leaving a dry, “star-like” central abdominal scar Two arteries Para-urachal lateral Single umbilical artery*
that forms the umbilicus. Failure of the umbilical ring to completely ligaments
close can result in an umbilical hernia, by far the most common umbili- One vein Round ligament of liver Phlebitis**
cal disorder. Discharge or abnormal tissue from the umbilicus is most Allantois Median umbilical liga- Patent urachus, urachal cyst
often due to an umbilical granuloma, but can result from incomplete ment or sinus
involution of the urachus or omphalomesenteric duct. Any discharge, Vitelline duct None Omphalomesenteric duct
mass, or sinus tract is pathological and should be appropriately evalu- remnant, umbilical polyp,
ated and treated. These and other umbilical disorders are discussed in Meckel’s diverticulum
further detail in this chapter.
Umbilical ring Physiologic closure; Umbilical hernia
Anatomy and Pathology fascia covering defect Omphalocele
The umbilical cord is the main portal for entry and exit of blood from Source: Minkes R.K.. Disorders of the Umbilicus. EMedicine Specialities. Available at: emedi-
the placenta to the foetus during intrauterine life. In addition to the cine.medscape.com/article/935618-overview; accessed 27 October 2008.
*Twenty-five percent of umbilical disorders with single umbilical arteries have as-
paired umbilical arteries and umbilical vein, the umbilical cord also
sociated congenital anomalies.
contains the vitelline or omphalomesenteric duct (which connects the
**A possible complication following umbilical vein catheterisation.
yolk sac to the midgut) and the allantois (the portion connecting the
umbilicus to the bladder becomes the urachus). Usually, the vitelline
duct obliterates by the 5th to 9th week of gestation, and the urachus prolong separation of the cord for up to 8 weeks. Dry cord care has
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obliterates to become the median umbilical ligament by the 4th to 5th been found to be effective in developed countries; however, in devel-
month. After birth, the umbilical cord withers and separates, leaving no oping countries, antiseptic cord care continues to be recommended,
remnants. Umbilical abnormalities can arise, however, when embryo- and has been found to decrease the incidence of and mortality from
1,2
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logical remnants persist or fail to completely involute. Table 57.1 omphalitis. Agents that have been used include 70% alcohol, silver
compares the embryological components of the umbilical cord with sulfadiazine, chlorhexidine, neomycin-bacitracin powder, and salicylic
related disorders. sugar powder. 6,7
Like skin anywhere on the body, the umbilicus may also be affected Aside from agents used in umbilical cord care, other factors that can
by a variety of dermatological conditions, such as hemangiomas, delay umbilical cord separation include infection, underlying immune
dermoid cysts, or mechanical irritation. A number of syndromes, such disorders (such as leukocyte adhesion deficiency), or an urachal
as the Aarskog, Reiger, and Robinow syndromes, are associated with abnormality. 7–10 On examination, the skin surrounding the umbilical
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an abnormal umbilical appearance. The umbilicus can also be found in cord remnant should be carefully examined for a urachal remnant or for
an abnormal position or even absent, as in bladder exstrophy. any evidence of infection; omphalitis (see next section) can be rapidly
Classification of Umbilical Problems progressive and life threatening in a neonate.
A complete blood count with a differential may be useful as an
Umbilical problems can be classified as follows, based on the aetiology initial screen for leukocyte adhesion deficiency. Even in the absence of
of the abnormality:
infection, leukocytosis and neutrophilia may be present in patients with
• acquired: delayed umbilical separation, umbilical granuloma; leukocyte adhesion deficiency. Rare neutrophil motility defects may
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• infectious: omphalitis, umbilical vein phlebitis; require a more sophisticated immunologic work-up.
If a patient presents with delayed separation of the cord, it may be
• congenital: omphalomesenteric duct remnant, umbilical polyp, patent either gently removed manually or divided just distal to normal skin
urachus, umbilical hernia, dermoid cyst, umbilical dysmorphism; or with scissors or a scalpel. After removal, the stump site should be
• neoplastic: rhabdomyosarcoma, teratoma. cleansed with an antiseptic agent and exposed to air.
Omphalitis
Selected Umbilical Pathology
Omphalitis is an infection of the cord stump or its surrounding tissues.
Delayed Umbilical Separation It presents most commonly in the newborn; the mean age at onset is 5–9
The timing of umbilical cord separation may vary, depending on ethnic days, or earlier in preterm infants. The risk of omphalitis is increased by
background, geographic location, and method of cord care. Cord sepa- a number of maternal factors (prolonged rupture of membranes, maternal
ration usually occurs 1 week after birth; persistence beyond 3 weeks is infection, amnionitis), factors at delivery (nonsterile or home delivery,
generally considered delayed. Various umbilical cord antiseptics can inappropriate cord care); and neonatal factors (low birth weight, delayed
prolong the separation time, however. For example, triple dye may cord separation, leukocyte adhesion deficiency, neonatal alloimmune