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Gastrointestinal (GI) motility disorders (GMDs) are represented
by a spectrum of conditions that range from benign prevalent disorders
(gastroesophageal reflux (GER) and childhood constipation) to more
rare and severe entities (chronic intestinal pseudo-obstruction
(CIP) and Hirschsprung’s disease). Altered GI motility
adds considerable co-morbidity to structural anomalies such as intestinal
atresia, stenosis, or gastroschisis. Pediatric GMDs are classified
according to the results of GI motility testing. It is likely that
with advanced methods of studying the brain–gut axis, classification
of these disorders will eventually be based on pathophysiology.
Within the pediatric population, GMDs are also known to be either
congenital or acquired, depending on the presence or absence of
symptoms at birth.1,2 Congenital disorders usually cause
symptoms within the first 2 months of life and can be sporadic or
familial. Acquired motility disorders present later in life and
can be secondary to a variety of insults including infections and
adverse reactions to medications.3 Within the pediatric
population, GMDs account for up to 15% of all intestinal
failures.
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Based on histopathology and patterns of motility abnormalities,
traditionally the causes of GMDs are also classified as visceral
neuropathy or visceral myopathy.3 Neuropathic disorders
are more common, but myopathies are usually associated with more severe
symptoms.2,3 The role of genetic mutations in visceral
neuropathies or myopathies has not yet been thoroughly elucidated.
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Other possible causes of motility disorders include intrauterine
ischemic insults, exposure to amniotic fluid,4 delayed
maturation of either the enteric nervous system or the interstitial
cells of Cajal,5 and disorder of the mitochondrial electron
transport chain enzymes.6 Inflammation within the myenteric
ganglia may cause severe progressive neuropathic CIP in conjunction
with autoimmune disease and circulating antienteric neuronal antibodies.7 Mitochondrial
myopathies are known to be associated with a variety of clinical
syndromes including CIP.8 Patients with mitochondrial neurogastrointestinal
encephalomyopathy (MNGIE) have GI dysmotility, peripheral neuropathy,
and ophthalmoparesis, and muscle biopsy shows histological features
of mitochondrial myopathy.1,9,10
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While treatment of motility disorders has improved significantly
over the last two decades, treatment options remain relatively limited.
Motility disorders produce nutritional and electrolyte deficiencies,
chronic and recurrent vomiting, fecal incontinence, chronic and
recurrent pain or discomfort, reduced independence in daily life,
and reduced mobility. A wide range of clinical skills is often required
to optimally treat these patients. Centers specializing in this
care generally establish a multidisciplinary team approach. As part
of the treatment, psychological and social support efforts are extremely
necessary to achieve optimal outcomes.
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Given the number of pediatric GMDs and the space limitations
of this chapter, only the following six motility disorders will
be reviewed:
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- esophageal achalasia (EA);
- motility disorders following repair of congenital intestinal
atresias;
- motility disorders associated with gastroschisis;
- CIP;
- motility disorders following intestinal transplantation;
- Hirschsprung’s disease.
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Definition and
Epidemiology
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EA is a primary esophageal motility disorder ...