An intestinal polyp is defined as a tissue mass that projects
from the wall of the bowel into the lumen. It can be broadly classified
into two main categories, neoplastic and non-neoplastic. Within
each category, there are multiple potential types of lesions, some
of which are associated with a syndrome including multiple polyps,
some of which may carry a risk of cancer, and others which are less
numerous and unlikely to cause future problems. The neoplastic polyps
typically have an abnormal epithelial component resulting from abnormal
proliferation. Non-neoplastic polyps can be either hamartomas, with
involvement of all three germ layers, or inflammatory in nature.
A child with polyps typically presents with painless rectal bleeding,
although larger polyps can be associated with pain if they cause
obstruction, if motility-induced traction on the polyp results in stretching
of mesenteric attachments, or if a polyp serves as a lead point
for intussusception. Polyps may be encountered in any region of
the intestine, although the region most commonly affected is the
colon. They may occur sporadically, or there may be a strong familial
component. It is therefore important to obtain a thorough family
history of polyps and gastrointestinal cancers.
The most common of the intestinal polyps encountered in childhood
is the juvenile polyp, a benign non-neoplastic
tissue growth with a marked propensity for causing rectal bleeding.1 These
are relatively common, with most cases occurring before age 10 years
and peaking at around ages 2–5 years. Isolated juvenile
polyps are not associated with a genetic disorder and therefore
not typically associated with a family history of polyps. If such
history exists, other conditions must be suspected.
The etiology of isolated juvenile polyps is not well understood.
In contrast to juvenile polyposis, in which multiple similar polyps
occur throughout the GI tract (see below), there is no associated known
gene mutation. Similar-appearing polyps (inflammatory polyps) are
seen in children and adults with intestinal inflammation, and it
is therefore likely that these lesions are in some way related to
an inflammatory process. Long-term follow-up of patients with isolated
juvenile polyps reveals no evidence of increased risk of intestinal
malignancy,2 which is in marked contrast to juvenile polyposis
Children with juvenile polyps typically present with recurring
episodes of small-volume, bright red rectal bleeding, not associated
with any abdominal discomfort or significant anemia. Bleeding appears
to be caused by intestinal contents moving across the friable surface
of these polyps, causing mechanical trauma and resulting in bleeding.
Occasionally, more brisk bleeding can occur if the head of the polyp
is avulsed from its stalk, creating a very brief and hemodynamically
insignificant higher volume bleeding episode.
At endoscopy, no lesions are found in the upper gastrointestinal
tract, and fewer than five polyps are seen during ...