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Abdominal pain is among the most common complaints in children, accounting
for approximately 10% of all children evaluated in emergency
units. Abdominal pain can be acute and sudden in onset or chronic
with continual or intermittent symptoms. Most episodes of pain are
benign and resolve with minimal or no intervention.1 One
recent study showed that only 23% of all children evaluated
in an emergency department required surgical intervention, most
often for appendicitis.1 Differentiating abdominal
pain that requires prompt surgical intervention from pain due to
nonsurgical conditions is often challenging, especially in the infant
and toddler. The evaluation and management of abdominal pain varies
depending on the severity and character of the pain, associated
symptoms, and age and sex of the child. The difficulties in diagnosis
can be reduced by considering the most likely diagnosis based on
the child’s age, the presence of associated symptoms, and
the physical examination.
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The sensation of abdominal pain is transmitted to the central
nervous system via somatic and visceral afferent fibers. The visceral
afferent system innervates the visceral peritoneum and its structures.
Visceral pain localizes poorly, but pain originating from the stomach,
duodenum, and pancreas generally localizes to the epigastrium; pain
originating from the small bowel, colon, and spleen localizes to
the periumbilical region; and pain originating from the rectosigmoid
and bladder localizes to the hypogastrium. Renal or ureteral pain
is usually localized to the flank. Gallbladder pain is often poorly
localized but may localize to the right upper quadrant. Pain originating
from the parietal peritoneum from inflammation or abdominal wall
pain is well localized. Referred pain results from the convergence
of visceral and somatic pain pathways in the spinal cord, so pain
originating in abdominal viscera may be perceived as originating
at a distant, well-isolated somatic location. For example, diaphragmatic
irritation secondary to pancreatitis, a bleeding spleen, cholecystitis,
or liver abscess may be interpreted as pain arising in the vicinity
of the lower neck and shoulders because the diaphragm and shoulder
pain pathways converge in the spinothalamic tracts at C4. Similarly,
gallbladder inflammation may be sensed in the right infrascapular
region, pancreatic pain may be sensed in the posterior flank, a
migrating ureteral stone may be felt progressing toward the ipsilateral groin,
and rectal and gynecologic discomfort may be sensed in the vicinity
of the sacrum. Conversely, pain originating in somatic locations,
such as the right pleural surface with pneumonia, may be perceived
as originating in the lower abdomen because pain afferents from both
regions converge at T10-11.
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Clinical Features
and Differential Diagnosis
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Pain of sudden onset is likely associated with colic, perforations,
and acute ischemia (eg, torsions, volvulus). Slower onset of pain
generally is associated with inflammatory conditions such as appendicitis,
pancreatitis, and cholecystitis. Colic results from spasms of a hollow
muscular viscus (eg, biliary tree, pancreatic duct, gastrointestinal
tract, urinary system, uterus and fallopian tubes) and is usually
secondary to ...