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CHAPTER 68

Intussusception

Afua A.J. Hesse
Francis A. Abantanga
Kokila Lakhoo

Introduction The most common PLP in the causation of nonidiopathic intus-
Intussusception is the most common type of intestinal obstruction seen susception, especially in older children, is Meckel’s diverticulum, 4,13–15
in the paediatric age group, especially in infants and toddlers. It is an followed by polyps of the small intestine and colon. 11,12,14,15 Other PLPs
occlusive-strangulation type of intestinal obstruction, and all necessary include intestinal duplications, lymphomas, haemangiomas, lympho-
measures should be taken early to ensure prompt diagnosis and treatment sarcomas, enteric cysts, Henoch-Schönlein purpura with submuco-
in order to prevent ischaemia and necrosis of bowel. Intussusception sal haematomas, cystic fibrosis with inspissated meconium, benign
occurs when a portion of the proximal bowel (usually referred to as the intestinal neoplasms, Peutz-Jeghers familial polyposis, ectopic gastric
intussusceptum) telescopes into a segment of the adjoining distal bowel mucosa, ectopic pancreatic mucosa, and worm infestations (especially
(known as the intussuscepiens). The intussusceptum is propelled further Ascaris lumbricoides). The proportion of intussusceptions with a PLP
13
into the intussuscepiens by peristalsis and eventually becomes thickened, increases with age. Intussusception may also occur in children as a
oedematous, and swollen, leading to blockage of its lumen (occlusion) and result of trauma, such as a postoperative complication after abdominal
subsequent pinching off of its mesentery (strangulation). surgery, 3,12,13 especially retroperitoneal surgery, and after immunization
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Children with intussusception in the African subregion, as a rule, with rotavirus vaccine.
present lateto hospital for management 1,2,3 as a result of lack of knowledge Pathophysiology

on the part of parents, who try assorted local remedies before bringing the An imbalance of the longitudinal forces along the intestinal wall is
child to hospital. believed to be the cause of intussusception. This lack of homogene-
9,11
Diagnosis of the condition can be difficult and tricky, sometimes ity of longitudinal forces along the intestinal wall can be caused by a
4
causing diagnostic confusion with other conditions, such as enterocolitis, mass acting as a lead point or may result from a disorganized pattern
dysentery, and gastroenteritis, further delaying the diagnosis. When the of peristalsis. Because of the imbalance between the contractions of the
diagnosis is made late (meaning more than 48 to 72 hours after symptoms circular muscles perpendicular to the axis of the longitudinal forces, a
develop), surgery is usually the only option left to most surgeons. About kink develops in the abnormal portion of the intestine, thus creating a
90–95% of intussusceptions occur in children between the ages of 3 fulcrum for infolding of this area, resulting in its invagination into the
months and 3 years, and usually do not have a pathological lead point adjacent distal bowel (Figure 68.1). The telescoped intestine then acts
5,6
(i.e., they are idiopathic in nature). 6
as the apex of the intussusception (known as the intussusceptum) and
Demographics completely invaginates into the distal portion of the bowel that receives
Intussusception is known to occur among children in Africa, but unfor- it (the intussuscipiens) (Figure 68.2). The process of invagination con-
tunately its true incidence is not known. It is seen with striking variation tinues, the mesentery is pulled along with the intussusceptum and can
in frequency in various parts of the world. Worldwide, the incidence is travel all the way to the rectum, and as the intussusceptum progresses,
estimated to be approximately 2–4 cases per 1,000 children, with a male- the lymphatic return is first impeded and eventually venous drainage is
to-female ratio ranging from 1.4:1 to 3:2. 1-4,7-9 The male preponderance is impaired as a result of increased pressure in the wall of the intestine,
more remarkable in the latter months of infancy. Intussusception tends to leading to congestion and oedema of the intussusceptum.
occur in well-nourished infants, around the time of weaning of the infant; Eventually, the arterial blood supply to this segment of bowel
its incidence in malnourished children is less than 30%, as quoted in the is obstructed. The mucous membrane, which is very sensitive to
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literature from Africa. No paediatric age group is exempt from having ischaemia, sloughs off first and is passed out as mucous stools initially;
intussusception, but it is more common in infants and toddlers. After 3 the ischaemic mucosa bleeds when it sloughs off in the end, and this
years of age, anatomically identifiable pathological lead points (PLPs) may
9,11
be the cause of an intussusception in about 1.5% to 12% of children.
Aetiology
In most childhood intussusceptions, the cause is usually unknown; this
type of intussusception is referred to as idiopathic. This is the case in
90–95% of intussusceptions found in infants and toddlers. In this group
of children, there may be hypertrophy of the mural lymphoid tissues,
known as Peyer’s patches, in the terminal ileum as a result of a viral illness
(caused by adenovirus or rotavirus) with a history of acute gastroenteritis
and/or respiratory tract symptoms. Operative findings in these children
often include enlarged mesenteric lymph nodes and Peyer’s patches. 11,12 (A) (B)
In others, a mobile caecum is found. In most hospital-based studies in the Figure 68.1: Two infants with manually reduced intussusception: (A) infolding or
subregion, in children younger than 3 years of age with intussusception, indentation of the terminal ileum where the intussusceptum started; (B) infolding
10–30% were found to have had gastroenteritis. of the caecum, resulting in a caeco-colic intussusception.
1,10