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CHAPTER 20

Omphalitis

Mairo Adamu Bugaje Emmanuel A. Ameh
Merrill McHoney Kokila Lakhoo

Introduction Cellulitis
Omphalitis is defined as infection of the umbilicus—in particular, the Necrotising fasciitis
umbilical stump in the newborn. It primarily affects neonates, in whom Abdominal wall abscess
the combination of the umbilical stump and decreased immunity presents
an opportunity for infection. It is rarely reported outside the neonatal
period. Varieties of congenital conditions predispose to infection of the spread Abdominal wall
umbilical stump and are also among the differential diagnoses to consider
for the presentation.
Liver
Omphalitis may extend into the portal vein and result in various abscess
acute complications requiring medical as well as surgical interventions. Umbilical Umb. vessel
hernia
Although this condition is uncommon in developed countries, it Local Omphalitis spread Septic
Weakness emboli
remains a significant cause of morbidity and mortality in Africa and Evisceration
Portal vein
other parts of the world where health care is less readily available. thrombosis
Umbilical cord infection contributes significantly to newborn infection
and neonatal mortality in Africa, especially for infants delivered at spread Peritoneal
home without skilled birth attendants and under unhygienic conditions. 1
Demographics
Omphalitis is uncommon in developed countries, with an incidence of Peritonitis
0.2–0.7%. The incidence in developing countries has been quoted to be Intraabdominal abscess
1
Adhesions
between 2 and 7 in every 100 live births. However, the incidence is
2,3
even higher in communities that practise application of nonsterile home Figure 20.1: Pathophysiology of surgical complications of omphalitis.
remedies to the cord. In one study of neonates admitted to an African
general paediatric ward, omphalitis accounted for 28% of neonatal defences, and it undergoes ischaemia and degradation as the umbilical
4
admissions. Hospital-based studies estimate that 2–54 babies per 1000 stump dries and falls off. Normally, the cord area becomes colonised
births will develop omphalitis. However, one report from Tanzania 6 with potential bacterial pathogens intrapartum or immediately postna-
5
found a rate of 1.7% among babies of 3,262 women. tal. Bacteria have the potential to invade the umbilical stump, leading
Although there is a male preponderance, there does not appear to be to omphalitis. The pathophysiology of complications of omphalitis is
a racial or ethnic predilection to developing omphalitis. The mean age closely related to the anatomy of the umbilicus. The infection can spread
of onset is usually 3–5 days for preterm infants and 5–9 days for term along the umbilical artery, umbilical veins, abdominal wall lymphatics
infants. For those with complications, the age at presentation is 5–75 and vessels, and by direct spread to contiguous areas (Figure 20.1).
days (median, 33 days), according to one report. 7 The bacteriological spectrum of omphalitis is undergoing change,
Unhygienic cord practices have been implicated as the main factor in light of the changes in cord care, antibiotic use, bacterial resistance
responsible for the high incidence of omphalitis in Africa. Risk factors profiles, and local practices. A single organism is causative in
include inappropriate cord handling (e.g., cultural application of substances most cases. More often, aerobic organisms are causative. Common
such as engine oil, cow dung, talc powder, or palm oil to the cord); septic organisms include:
delivery secondary to prolonged rupture of membranes or maternal
infection; nonsterile delivery; prematurity; and low birth weight. One • Staphylococcus aureus (most common)
report cited use of old instruments to cut the cord, mother not bathing • Group A streptococcus
1
(washing the perineum with water and soap) or shaving before delivery,
and application of substances on the umbilical cord to be independently • Escherichia coli
associated with the risk of developing omphalitis. Other risk factors • Klebsiella
include neonates with weakened or deficient immune systems or who
are hospitalised and subjected to invasive procedures such as umbilical • Proteus
catheterisation. Genetic defects in contractile proteins have been implicated, Up to one-third of cases of omphalitis are associated with anaerobic
and in some, immunological factors such as leukocyte adhesion deficiency infection caused by:
(LAD) syndrome and neutrophil mobility may play a role. • Bacteroides fragilis
Aetiology/Pathophysiology • Peptostreptococcus
The umbilical cord presents a unique substrate for bacterial colonisa-
tion. It is relatively rich in substrate, without the normal barrier of skin • Clostridium perfringens