++
Chronic abdominal pain is characterized by intermittent or persistent
pain that occurs over a period greater than 2 months. Chronic or
recurrent abdominal pain (RAP) is reported to occur in 10% to
15% of children between the ages of 4 and 16 years and
accounts for 2% to 4% of all pediatric office
visits.1 RAP is not a diagnosis but is a descriptive
term that applies to intermittent, severe, episodic pain. It is
frightening to both families and care providers who are concerned
that it is a harbinger of serious disease such as an infectious,
inflammatory, metabolic, anatomical, or neoplastic disorder. However,
in most cases, the pain is functional, without
demonstrable evidence of a pathological condition. Functional pain
disorders often impact school attendance and performance, peer relationships,
and participation in organizations, sports, and personal and family
activities.
++
An evolving understanding of the mechanisms of functional pain
disorders suggests that a transient noxious event or inflammatory
event results in a persistent sensitization of neural pain pathways,
altering the conscious awareness of gastrointestinal sensory input,
also described as visceral hyperalgesia. An example
of this hyperalgesia is found in a subset of patients with functional
abdominal pain who experience exaggerated pain compared to normal
subjects during equal pressures of balloon distension in the rectosigmoid.
The lower sensory pain threshold observed in patients with functional
abdominal pain (FAP) may be due to increased responsiveness of intraluminal
mechanoreceptors, primary sensory afferent neurons, second-order
neurons in the spinal cord, or abnormal processing of sensory information in
the brain. Some patients with FAP may also experience headaches,
dizziness, motion sickness, pallor, temperature intolerance, and
nausea, suggesting a generalized dysfunction of the autonomic nervous
system. The central corticotropin-releasing factor system has also
been implicated in mediating the effects of early life stress and
possibly contributing to the development of abnormal reactivity
of the hypothalamic-pituitary-adrenal axis to stress later in life.2
++
The neuronal circuitry involved in pain sensation develops during
the early neonatal period and requires use-dependent activity for
appropriate development. Noxious stimuli or stress during this critical
period of development appears to decrease the sensory thresholds
and increase pain responses. Neonatal rat exposure to either repetitive
colorectal distension or colonic irritation results in permanent
alterations in spinal dorsal horn neurons and persistence of visceral
hyperalgesia in adulthood.3 Several findings in
humans suggest that sensitization in early life may not result in
persistent symptoms but may predispose a child to develop hyperalgesia
in response to later injury or stress. Infants who undergo surgery
require higher fentanyl dosages intraoperatively than do infants
with no previous surgery.4 Similarly, infants with
prenatally diagnosed hydronephrosis demonstrate increased abdominal
sensitivity compared to controls.5 Early childhood
behavioral experiences may also impact later pain responses. Survivors
of child abuse have higher stress vulnerability and are more likely
to develop irritable bowel syndrome.
++
Psychological comorbidities may also increase the likelihood
of a child having visceral hyperalgesia. Up to 80% of children
with functional abdominal pain have some form of anxiety, and approximately
40% will meet the criteria for a depressive disorder.6 Genetic
vulnerability for functional disorders is suggested by a high frequency
of functional disorders among family members. Sex, intelligence,
and personality traits do not distinguish patients with functional
pain from those with organic pain. The generalization that patients
with functional abdominal pain are perfectionists, overachievers,
or constant worriers is without foundation.
+++
Clinical Features
and Differential Diagnosis
++
Pain behaviors include grimacing, verbalizing, sighing, visibly
guarding abdominal muscles, and rubbing the painful area. Children with
chronic pain often undergo lifestyle alterations that include decreased
school attendance, participation in age-appropriate activities,
and alteration in eating behavior or sleep pattern. The diagnostic
evaluation begins with a history to distinguish chronic from acute
pain, to identify alarm signs that indicate underlying pathology
and trigger specific investigations, and then subcategorizing the
clinical presentation of functional pain disorders. Chronic abdominal
pain is described as intermittent or persistent pain for greater
than 2 months. Alarm signals that raise suspicion of an underlying
organic disorder are listed in Table 384-1. These include continuous pain, pain
localized away from the umbilicus, pain or diarrhea repeatedly awakening
the patient from a sound sleep, pain related to menstrual cycle,
back pain, multisystem complaints, anorexia, weight loss, frequent
vomiting, evidence of gastrointestinal bleeding (hematemesis, melena,
hematochezia, rectal bleeding, occult bleeding), profuse diarrhea,
encopresis, extraintestinal symptoms (fever, rash, joint pain, recurrent
aphthous ulcers), and a positive family history of inflammatory
bowel disease, peptic ulcer, or migraine headache. Physical findings
include linear growth deceleration; localized tenderness in the
right upper or lower quadrant; localized fullness or mass effect;
hepatomegaly; splenomegaly; back or costovertebral angle tenderness;
perianal fissure, fistula, or soiling; and occult blood in stools.
Laboratory findings of iron deficiency anemia, an elevated sedimentation
rate or C-reactive protein, hypoalbuminemia, abnormal liver or kidney
function tests, and elevated amylase or lipase are also concerning.
++
++
In the absence of alarm signals, a functional gastrointestinal
disorder should be considered. These disorders have been classified
by the Rome III International Working Team Committee as functional
abdominal pain of childhood (FAP), irritable bowel syndrome (IBS),
functional dyspepsia (FD), and abdominal migraine (eTable 384.1).2 These diagnostic
definitions require that the episodic or chronic pain occur over
a period longer than 2 months; however, in clinical practice, patients
do not often present in a typical fashion, and a presumptive diagnosis
is often made when symptoms persist for more than 2 weeks. Management
of these patients should not await fulfillment of these strict criteria.
Furthermore, many patients do not fit clearly into any of the groups.
Despite these limitations, the Rome classifications provide a framework
to allow a working diagnosis of a functional pain syndrome based
on history, physical examination, and a focused laboratory evaluation.
++
+++
Diagnostic Evaluation
++
A stepwise approach to diagnosis and treatment of functional
pain is outlined in Table 384-2. In patients
without alarm signals, a working diagnosis of functional abdominal
pain should be introduced to the family at the initial evaluation.
If any additional laboratory or radiographic evaluation seems warranted
on the basis of alarm signals, it is useful to explain to the family
that tests are being performed to rule out any serious disorders
but that a functional disorder likely explains the clinical presentation.
If these same tests are performed with an apparent expectation that
disease is present, even normal results often will not allay the
family’s anxiety about more serious disease. Functional pain
should be presented as a positive diagnosis, and further focused
diagnostic testing and treatment strategies described in this chapter
can be initiated.
++
++
The diagnostic possibilities and the approach to evaluation of
chronic abdominal pain vary depending on the presence of associated
symptoms. Establishing a working diagnosis of functional pain and
initiating conservative therapy does not preclude a later focused
diagnostic workup when indicated by emerging alarm signals. Thus,
the care provider should not feel obligated to perform multiple
tests to rule out an organic etiology for the pain. In fact, such
an approach can lead to increased anxiety and frustration that a
cause of the pain is not being found, and families often become
invested in finding a cause because they believe that if the physician undertook
such an extensive evaluation, the symptoms must suggest a serious
disorder. Recurrent testing leads to increasing anxiety about the
symptoms, and the focus on symptoms can contribute to progressive
disability.
++
Psychological stressors may provoke all forms of functional pain
by altering the conscious threshold of gastrointestinal sensory
input in the central nervous system. A history of death or separation
of a significant family member, physical illness or chronic handicap
in parents or sibling, school problems, altered peer relationships,
family financial problems, or a recent geographic move are all likely
to precipitate symptoms in susceptible individuals.
+++
Isolated Recurrent
Abdominal Pain
++
Isolated recurrent abdominal pain most often presents a pattern
of episodic, acute, intense midline abdominal pain lasting a few
hours to several days with intervening symptom-free intervals lasting
days to months. Commonly associated symptoms include headache, pallor,
dizziness, and fatigue, at least one of which is observed in 50% to
70% of cases. Although many children complain of pain at
the time of office visits, their behavior, affect, and activity
are seldom consistent with the degree of expressed discomfort. Poorly
localized pressure tenderness is frequently elicited during abdominal
palpation. Between episodes, the abdominal examination is normal. Table 384-3 lists the major differential
diagnoses of recurrent, periumbilical abdominal pain in children.
++
++
Occult constipation should be suspected if a left lower quadrant
or suprapubic fullness or mass effect is appreciated on abdominal
examination. Constipation should also be suspected if the rectal
examination reveals evidence of firm stool in the rectal vault or
soft stool in a dilated rectal vault with evidence of perianal soiling.
Often, a history of constipation is unknown to the parent. Gross
inspection of the perianal area may reveal fistulas or tags suggestive
of Crohn disease. It is important to recognize that Crohn disease
can present with isolated abdominal pain and often with a history
suggestive of constipation. Recurrent fevers, aphthous ulcers, or
rash in patients with abdominal pain should prompt an investigation
for inflammatory bowel disease. During the evaluation, it is also
important to determine whether pain is arising from the abdominal
wall or has an intra-abdominal origin. The Carnett test is
useful in this situation. The site of maximum tenderness is found
through palpation. The patient is then asked to cross his or her
arms and assume a partial sitting position (crunch), which results
in tension of the abdominal wall. If there is greater tenderness
on repeat palpation in this position, abdominal wall disorders such
as cutaneous nerve entrapment syndromes, abdominal wall hernia,
myofascial pain syndromes, rectus sheath hematoma, or costochondritis
should be suspected. Discitis may present as a combination of back
and abdominal pain. The condition is usually associated with intermittent
fever, elevated peripheral white blood cell count, and elevated
erythrocyte sedimentation rate. Pain with palpation over a rib may
suggest a diagnosis of costochondritis or painful
rib syndrome, which is often misinterpreted as representing
abdominal pain.
++
Appendiceal colic and chronic appendicitis are controversial
entities that cause chronic abdominal pain associated with recurrent
acute episodes of well-localized abdominal pain and tenderness,
most commonly in the right lower quadrant, demonstrated on several
examinations (see Chapter 413). Dull, midline,
or generalized lower abdominal pain at the onset of a menstrual
period suggests dysmenorrhea. The pain may coincide with the start
of bleeding or precede the bleeding by several hours. Gynecologic disorders
associated with secondary dysmenorrhea include endometriosis, partially
obstructed genital duplications, ectopic pregnancy, and adhesions following
pelvic inflammatory disease. Cystic teratoma has been described
in prepubertal patients presenting with right or left lower quadrant
pain. The vast majority of such patients have a palpable abdominal
mass. Benign ovarian cysts in adolescent girls do not cause recurrent
abdominal pain. Recurrent fever associated with generalized abdominal
pain and peritoneal signs suggest the possibility of familial Mediterranean
fever. Acute intermittent porphyria is a rare disorder characterized
by the temporal association of paroxysmal abdominal pain and a wide
variety of central nervous system symptoms, including headache,
dizziness, weakness, syncope, confusion, memory loss, hallucinations,
seizures, and transient blindness. Acute intermittent porphyria
is often precipitated by low intake of carbohydrate or by specific
drugs such as barbiturates or sulfonamides.
++
No laboratory tests or radiographic evaluation is routinely required
to manage children with a typical presentation of isolated recurrent
abdominal pain, although screening laboratory studies are usually
performed. These include a complete blood count with differential,
urinalysis and urine culture, and erythrocyte sedimentation rate.
Some experts routinely perform a chemistry profile and serum amylase
as well as celiac disease screening tests. Low serum albumin along with
a high sedimentation rate and iron deficiency anemia is highly suggestive
of inflammatory bowel disease. Parasitic infections, particularly Giardia
lamblia, Blastocystis hominis, and Dientamoeba
fragilis, may cause chronic pain in the absence of altered
bowel pattern, so stool ova and parasite evaluation may be useful.
In adolescent females, pregnancy testing and culture for sexually
transmitted diseases may be necessary. Breath hydrogen testing for
carbohydrate malabsorption (lactose, sucrose, fructose) is of low
yield, as are food allergy tests. Upper gastrointestinal radiography
may aid in diagnosis of gastrointestinal structural disorders such
as a malrotation, internal hernia and intussusception, or inflammatory
disorders such as Crohn disease. Other rare conditions, such as
lymphoma, angioneurotic edema, mesenteric vein thrombosis with ischemia,
and pseudoobstruction, may also be identified. Abdominal ultrasound
and abdominal CAT scan have low diagnostic yields but may be useful
to identify appendiceal abnormalities, especially when pain is recurrently
localized to the right lower abdomen, suggestive of chronic appendicitis,
Crohn disease, cholelithiasis, and ureteropelvic abnormalities.
Colonoscopy and ileoscopy is necessary to confirm Crohn disease.
+++
Irritable Bowel
Syndrome
++
Irritable bowel syndrome (IBS) is characterized by an abnormal
frequency and/or consistency of stools (diarrhea or constipation), straining,
urgency, relief of pain with defecation, a feeling of incomplete
evacuation, passage of mucus, or a feeling of bloating or abdominal
distention. Table 384-3 lists the differential
diagnosis of abdominal pain associated with symptoms of altered
bowel pattern. Abnormal stool frequency may be defined as more than
3 bowel movements per day or fewer than 3 bowel movements per week.
Abnormal stool form includes loose/watery stool, lumpy/hard
stool, or passage of mucus with stool. Patients with IBS often report
alternating between diarrhea and constipation. Irritable bowel is
usually associated with the same autonomic-type symptoms and signs
observed in isolated functional abdominal pain. In patients with
diarrhea, the laboratory evaluation should include screening laboratory
studies described previously; measurement of C-reactive protein,
celiac disease screening studies, and stool samples for ova and
parasites and for Clostridium difficile toxin.
Lactose intolerance or malabsorption of other carbohydrates such
as sorbitol should be considered a potential primary etiology of
chronic abdominal pain in the presence of diarrhea. A trial of a lactose-free
diet or performance of a lactose breath hydrogen test is prudent
in children with pain associated with loose bowels, bloating, and
increased flatulence. In patients with persistent diarrhea or constipation,
the evaluation should include a thorough evaluation of possible
causes of these symptoms, as outlined in Chapters 385 and 386.
+++
Abdominal Pain
Associated with Dyspepsia
++
Abdominal pain associated with symptoms of dyspepsia is characterized
by pain or discomfort localized in the upper abdomen, pain related
to eating, nausea, bloating, early satiety, and occasional heartburn
and oral regurgitation. Table 384-3 lists
the differential diagnosis of abdominal pain associated with symptoms
of dyspepsia. Concurrent anorexia, vomiting, weight loss, or evidence
of gastrointestinal bleeding (hematemesis, melena, occult bleeding)
suggest an upper gastrointestinal inflammatory, infectious, or structural
disorder. Evaluation of these alarm signals may require screening
laboratory studies, radiographic testing, and possibly upper endoscopy
with biopsy to diagnose disorders such as malrotation, esophagitis,
gastritis, peptic ulcer disease, ureteropelvic junction obstruction,
and cholelithiasis. Other disorders, such as gastroparesis, chronic
cholecystitis, and biliary dyskinesia, are uncommonly associated
with this symptom presentation in children, so gastric emptying
tests, hepatobiliary scans to assess gallbladder emptying, and endoscopic
retrograde pancreatography are rarely indicated. In a patient without
alarm signals, a short-term (8 to 12 weeks) empiric trial of medical
therapy with a proton-pump inhibitor should be considered. Upper
endoscopy should be considered in untreated patients with symptoms
beyond 2 months, patients who fail to respond to short-term antisecretory
therapy, and patients in whom symptoms recur after the end of treatment.
++
Abdominal migraine is a variant of functional abdominal pain
and might comprise a continuum of other disorders, such as migraine
headaches and cyclic vomiting. It is characterized by paroxysmal,
intense pain that is usually periumbilical. Associated symptoms
include anorexia, nausea, vomiting, headache, photophobia, and pallor.
Abdominal migraine affects approximately 1% to 4% of
children and is more common in girls than in boys (3:2). All other causes
of episodic severe abdominal pain, including intermittent bowel
obstruction, obstructive uropathy, relapsing pancreatitis, biliary
tract disease, angioedema, porphyria, and intracranial space-occupying
lesions should be considered. Treatment approaches are similar to
those used for cyclical vomiting and for other forms of migraine
(see Chapters 382 and 565).
++
Management of functional pain is facilitated by early diagnosis,
parental education, reassurance, and the clear delineation of goals
of therapy. These are to alleviate the chronic symptoms and/or
to return the patient to normal functioning and improved quality
of life in spite of pain. Most families accept that emotional stressors
or anxiety can cause headaches or gastrointestinal symptoms. They
also recognize that different children have different levels of
pain tolerance. Reinforcement of these concepts, along with an explanation
of visceral hypersensitivity (see Pathophysiology section
above), provides the family with a better understanding of the cause
of the pain and increases the likelihood of their engaging in behavioral
treatment strategies. Providing a positive diagnostic label reinforces
the concept that further diagnostic testing to find a cause of symptoms
is not necessary.
++
Treatment of the pediatric patient with chronic abdominal pain
requires patience and a substantial time commitment. In certain
cases, simply identifying a major stressor can help the pediatrician
set manageable goals. A dearth of pediatric literature evaluating
treatment options contributes to uncertainty regarding the approach
to management, which further exacerbates the discomfort of practitioners
managing these patients. A positive clinical diagnosis, reassurance,
explanation of the pathophysiology, environmental modifications,
dietary modifications, and selective pharmacologic and/or
behavioral therapy constitute the mainstay of treatment.
+++
Behavioral Management
++
The first goal is to identify, clarify, and possibly reverse
physical and psychological stress factors that may have an important
role in onset, severity, exacerbations, or maintenance of pain.
Equally important is to reverse environmental reinforcers of the
pain behavior.
++
The morbidity associated with functional abdominal pain is rarely
physical but results from interference in normal school attendance
and performance; peer relationships; and participation in organizations,
sports, and personal and family activities. Only 1 of 10 children
with functional abdominal pain attends school regularly, and absenteeism
is greater than 1 day in 10 in 28% of patients. A common
misconception is that pain is the direct cause of the morbidity.
In fact, focus on symptom relief by parents, school, and physicians
reinforces the pain behavior. Increased attention and rest periods
during pain episodes along with tactile stimulation and medication
to alleviate pain symptoms further reinforces the behaviors. Parents and
the school must be engaged to support the child rather than the
pain. Regular school attendance is essential regardless of the continued
presence of pain. In many cases, it is helpful for the physician
to communicate directly with school officials to explain the nature
of the problem. School officials must be encouraged to be responsive
to the pain behavior but not to let it disrupt attendance, class
activity, or performance expectations.
++
Within the family, less social attention should be directed toward
the symptoms. It has been recently shown that complaints of pain
in children with functional pain can be significantly decreased
if parents use distraction techniques during episodes of pain, whereas
symptoms nearly double under conditions of parent attention.7 Consultation
with a child psychologist may be indicated when there is concern
about a maladaptive family, a need to teach or reinforce coping
mechanisms, or if attempts at environmental modification do not
result in a return to a normalized life style.
++
Referral for psychological treatment can be proposed as part
of a multicomponent treatment package to help the patient more successfully
manage the pain symptoms. Cognitive behavior therapy (CBT) and hypnosis
are shown to be effective in reducing physiologic arousal in patients
with functional bowel disorders and may alleviate symptoms in some
patients. CBT teaches the patient coping skills by reframing or
modifying maladaptive thoughts. Hypnosis and guided imagery can help
the child reduce gut sensations by focusing attention away from
the terrifying sensory experience of abdominal pain. There is also anecdotal
evidence for complementary therapies such as massage and acupuncture
alleviating less severe cases of abdominal pain. The effectiveness
of these techniques is largely dependant not only on the patient’s
willingness to participate but also on the capabilities of the therapist.
+++
Trigger Identification
++
Triggers that exacerbate bowel symptoms must also be identified,
with an attempt to modify them. Postprandial symptoms in functional
dyspepsia may be improved by eating low-fat meals or by ingesting
more frequent but smaller meals throughout the day. A high-fiber
diet is recommended for both diarrhea-predominant and constipation-predominant irritable
bowel, but care must be taken because excessive fiber in the diet
may result in increased gas and distension and actually provoke
pain. Similarly, avoidance of excessive intake of milk products
(lactose), caffeine, carbonated beverages (fructose), dietary starches
(corn, potatoes, wheat, oats), or sorbitol-containing products (vehicle
for oral medication, sugar substitute in gum and candy, ingredient
in toothpaste, and a plasticizer in gelatin capsules) is reasonable
if they provoke symptoms. Excessive gas in patients with irritable
bowel syndrome can be managed by advising the patient to eat slowly,
to avoid chewing gum, and to avoid excessive intake of carbonated
beverages, legumes, foods of the cabbage family, and foods or beverages
sweetened with aspartame.
+++
Pharmacologic
Therapy
++
Symptom-based pharmacological therapy can be useful in selected
cases but must be used judiciously as an adjuvant to a multifaceted
approach. There are currently no evidence-based data on the effects of
pharmacologic therapy in pediatric patients with functional dyspepsia.
However, specific treatments may be of benefit in the right clinical
setting. As described above, short term, empiric treatment with
proton pump inhibitors is acceptable as an initial trial in patients
with functional dyspepsia. There are very few evidence-based data
on the effects of pharmacologic therapy in pediatric patients with
irritable bowel syndrome. Enteric-coated peppermint oil capsules
have been shown to improve abdominal pain scores in children with
irritable bowel syndrome (IBS)–like symptoms.8 However,
there was no significant improvement in associated symptoms such
as gas, stool pattern, or stool consistency. In IBS patients in
which the predominant symptom is diarrhea, synthetic opioids such
as loperamide and diphenoxylate may be effective. Loperamide is
preferred over diphenoxylate because it does not cross the blood-brain
barrier. For patients with IBS in which the predominant symptom
is constipation, nonstimulating laxatives such as mineral oil, milk
of magnesia, lactulose, or polyethylene glycol may be effective
adjuncts. Fiber supplements such as psyllium, methylcellulose, or
polycarbophil are effective in treating both constipation and diarrhea,
but their value in relief of IBS–associated abdominal pain
is controversial.
++
Novel drugs for treatment of irritable bowel syndrome in adults
include 5-hydroxytryptamine (5-HT3 and 5-HT4)-receptor
agonists and antagonists aimed at reducing visceral hypersensitivity
and altering bowel habits. Alosetron led to symptom improvement
among adult women with diarrhea-predominant irritable bowel syndrome,
but because of complications of ischemic colitis, it is available
only in a restricted manner. Tegaserod was shown to improve symptoms
in adolescents with constipation-predominant irritable bowel syndrome.
In a recent retrospective study in children, tegaserod improved
global assessment scores for constipation, abdominal pain, and bloating
without serious side effects.9,10 Marketing of
tegaserod was suspended in the United States in 2007 following reports
of cardiovascular ischemic events in adult patients.
++
Antispasmodic/anticholinergic agents are commonly used
in clinical practice to treat functional bowel disorders, although
efficacy is controversial. Anticholinergic agents block the muscarinic
effect of acetylcholine and can theoretically slow intestinal motility,
reduce spasm, and improve diarrhea. There are no good pediatric
trials evaluating effectiveness in children with chronic abdominal
pain or irritable bowel syndrome. Hyoscyamine and dicyclomine are
used occasionally in children but are useful only for predictable
episodes of pain. Long-term use in children may be associated with
significant side effects such as dry mouth, urinary retention, blurred
vision, tachycardia, drowsiness, and constipation.
++
Although there is a lack of formal randomized, placebo-controlled
trials, there has been a recent surge in the use of antidepressant
and psychotropic agents to treat both diarrhea-predominant irritable bowel
syndrome and functional dyspepsia in adults.11 There
are as yet no data on treatment of pediatric patients. Anecdotally,
this class of drugs appears to be effective in adults with or without
psychiatric abnormalities, especially low-dose tricyclic antidepressants.
These drugs may act as “central analgesics” to
raise the perception threshold for abdominal pain or downregulate
pain receptors in the intestine. The dose used to treat visceral
pain is relatively small (0.2 mg/kg) and is used as a single
bedtime dose. Desipramine can be used as an alternative if the sedative
properties are undesired. Because of the potential for causing cardiac
dysrhythmias in patients with prolonged QT syndrome, an electrocardiogram
prior to starting therapy is generally recommended.
++
Hospitalization is rarely indicated for patients with functional
abdominal pain. Fifty percent of patients experience relief of symptoms
during hospitalization. However, hospitalization does not enhance the
fundamental goals of environmental modification. More commonly,
it reinforces pain behavior.
++
There are no prospective studies of the outcome of any of the
various presentations of functional abdominal pain in childhood.
Following the diagnosis of functional abdominal pain, an occult
organic disorder is very rarely identified. The pain resolves completely
in 30% to 50% of patients within 2 weeks of diagnosis,
which suggests a benefit of simple reassurance that the pain is
not due to a serious underlying disorder. However, 30% to
50% of children with functional abdominal pain in childhood
experience pain as adults, although in 70% of such individuals,
the pain does not limit normal activity. Thirty percent of patients
with functional abdominal pain develop other chronic complaints
as adults, including headaches, backaches, and menstrual irregularities.12 Based
on a small number of patients, Apley and Hale have described several
factors that adversely influence prognosis for a lasting resolution
of pain symptoms during childhood, including male sex, age of onset
at less than 6 years, a strong history of a “painful family,” and
more than 6 months elapsed time from onset of pain symptoms to establishment
of a functional diagnosis.13