Introduction
From the birth up to the adolescence, painful syndromes occur.
These pain complaints affect a significant number of children, causing
suffering to them and to their relatives, and still requiring social
expenses. During the 1st year of age, colic predominates; in preschool
children, the "growing pains" are the most frequent ones;
between 4 and 12 years of age, abdominal pain is frequent; and among
adolescents, cephalea is the most common complaint of pain ().
New organic causes of recurrent abdominal pain have been identified.
Information about the digestive tract motility in childhood start
to disseminate. It is established that the pain has a nociceptive
component (nervous structures that receive and transmit pain), and
an emotional component (mental state), both influenced by genetics,
individual experiences, and cultural environment. The knowledge
of biopsychosocial influences on the child and on recurrent pain
has increased ().
These acquisitions allow the arousal of new diagnostic and therapeutic
approaches to recurrent abdominal pain in childhood. Recurrent abdominal
pain is not only a symptom, but a distinct pediatric entity.
Definition and classification
Recurrent abdominal pain in children is defined as the occurrence
of three or more episodes of pain in the abdomen within a period
of 3 months or less. Such episodes are severe enough to interrupt
routine activities. The patient remains asymptomatic between the
pain crises (,).
Recurrent abdominal pain is the most common cause of recurrent
pain among school children. It may have organic or functional origin.
The latter is defined when no anatomical, infectious, noninfectious/inflammatory,
or biochemical cause is established for the pain().
Since the etiology and pathogenesis of functional recurrent abdominal
pain are not established, and since there are no specific markers,
it consists of an exclusive diagnosis, based on a detailed clinical
history, on an detailed physical examination, and on few laboratory
tests (,).
Recurrent abdominal pain may be manifested as isolated paroxysms
of periumbilical pain, as pain in the abdomen, pain with dyspepsia,
and abdominal pain with dysfunction of the digestive tract. Signs
and symptoms of dyspepsia include nausea, vomiting, regurgitation,
pyrosis, early satiety, hiccups, and abdominal discomfort. The manifestations
of dysfunction of the digestive tract include diarrhea, constipation,
and the feeling of incomplete defecation. Out of the cases of recurrent
abdominal pain, 75% are functional, with isolated paroxysms of pain
around the umbilicus; 20% present manifestations of dyspepsia or
dysfunction of the digestive tract. Only 5 to 10% of the children
with recurrent abdominal pain present organic cause (,).
Epidemiology
Several studies show that recurrent abdominal pain affects 10 to
18% of children between 4 and 16 years of age. These variations
are due to geographic and racial differences, as well as diagnostic
criteria. Other 15% of school children and adolescents present episodes
of abdominal pain for a period longer than 3 moths, but without
the compromising of routine activities ().
Girls are more affected, in a proportion of 1.5:1 in relation to
boys. It usually starts at 4 years of age, and presents a constant
increase in the number of cases between 4 and 5 years, with a decrease
after this age in boys, and a significant increase in the number
of new cases among girls up to 10 years of age ().
Determining the beginning of recurrent abdominal pain is important
for the prognosis. The early appearance of pain is associated with
its bad evolution.
Etiology and pathophysiology of functional recurrent abdominal
pain
In the etiology and pathophysiology of functional recurrent abdominal
pain, factors such as genetic predisposition, autonomic nervous
system, stress, and inflammatory process of the digestive tract
should be considered. Since there are patients who present concomitant
manifestations of dyspepsia and abnormal bowel movements, it seems
that several painful manifestations are due to the same process.
Controlled studies did not show any relationship between emotional
alterations and recurrent pain (,).
Psychic alterations are not primary causes of functional recurrent
abdominal pain, but emotional processes obviously work as pain-intensifying
factors.
In the families of children with functional recurrent abdominal
pain, the report of pain complaints, such as peptic ulcer, irritable
bowel, and migraine, are frequent; this suggests genetic predisposition
to pain and functional compromising in these patients. The presence
of cephalea, paleness, and dizziness in these children reveals the
autonomic nervous system involvement in the process. Stressful,
physical, and psychosocial factors usually cause the pain crises.
The extrinsic nerves of the bowels, and/or the central nervous system
probably have their roles in the threshold of the pain perception.
A discrete and unspecific inflammatory process is found in all the
digestive tract of children with functional recurrent abdominal
pain, which is a cause or a consequence of the altered intestinal
motility. This inflammation affects endocrine and neural functions
that influence immunologic processes. The immunocompetent cells
that are located in the intestine secrete cytokines and inflammatory
mediators that act in the enteric neurons. The intestinal and central
nervous systems modulate the immunologic response through neurotransmitters
and neuropeptides that affect the lymphocyte function. These inter-relations
have implications in the functional recurrent abdominal pain (,).
The pathogenesis mostly accepted in the present days for functional
recurrent abdominal pain consists of alterations in the gastrointestinal
motility and/or visceral hypersensitivity. The specific pattern
of intestinal motor alterations during functional recurrent abdominal
pain has not been determined yet. Studies in heterogeneous groups
of adults with functional recurrent abdominal pain show an increased
intensity of intestinal muscular contraction and increased transit.
Few controlled studies in children show increased intestinal transit,
exacerbated colonic motor response to pharmacological stimulation,
and great-amplitude duodenal contraction (,,).
The increase in the visceral pain sensitivity in children with
functional recurrent abdominal pain is suggested by studies carried
out in adults with irritable bowel who show a decrease in the pain
threshold in all segments of the digestive tract ().
The improvement of recurrent pain with the withdrawal of the diet
of gas production operators (lactose, fructose, sorbitol), which
provoke the distension of the digestive tract, or of the diet of
fatty acids, which modify the enteric motility, point out to alterations
in the visceral sensitivity or in the intestinal motility, which
are present in the functional recurrent abdominal pain (,,).
A recent study with children presenting functional recurrent abdominal
pain showed a decrease in the pain threshold induced by pressure
in all the body surface; this study suggests the compromising of
the central nervous system at these patients' pain perception. The
decreased pain threshold would predispose or would start the pain
crises ().
Factors that intensify functional recurrent
abdominal pain
Children with functional recurrent abdominal pain usually present
a bad adaptation to the painful process. These factors that intensify
the crises are of environmental, behavioral, and emotional origin,
and make the children feel more pain, or predisposing them to new
episodes of pain.
Environmental factors
Patients with functional recurrent abdominal pain do not know about
the etiology and prognosis of the pain crises. They maintain expectations
that the pain will improve. They are unable to avoid new episodes
of pain, and they do not dominate the techniques that could make
the pain milder. As a consequence, an increase in the emotional
stress occurs, predisposing to a higher pain perception. Little
knowledge about pain makes the parents attribute the cause of the
crises to certain external factors, such as foods, environmental
conditions, and routine activities of the child's life. The anxiety
of the child when facing these false causative factors provokes
the onset or the aggravation of the pain. The patient starts to
present a phobic behavior, with restrict social and school activities,
and his/her life becomes different from other children's. These
stress creates or intensifies the
episodes of pain ().
Behavioral factors
What children know about pain comes from their own experience,
from the knowledge received from their parents, relatives and from
the society in general. They learn how to communicate the crises
with words and behavioral changes, and acquire techniques to relieve
the painful process. Usually, the parents do not know how to deal
with the pain, and respond ambiguously to the crises. Sometimes,
they have great physical and emotional care. In other episodes,
they suggest that the patient is the only responsible for the pain
handling. The child understands that the painful manifestations
should be communicated with exaggerated attitudes, in order to receive
a better parental support. This behavior maintains the pain. The
parents also encourage the child not to go to school after crises,
resting instead, to avoid physically stressful activities, to skip
social compromises, to avoid doing unpleasant activities. They dismiss
the child of familial responsibilities. So, there are secondary
benefits that start or prolong the painful process. The child becomes
frustrated, isolated, and anxious. He/she acquires passive attitudes
towards the pain, and this passivity intensifies the painful perception.
All these learning processes are going to maintain and intensify
the functional recurrent abdominal pain ().
Emotional factors
The recurrent pain is aversive, causing prolonged stress in
the patient and his/her family. The child becomes anxious, frustrated,
angry, sad, and depressed. These emotions intensify the stress that
starts or maintains the pain, creating a vicious circle: pain -
emotional stress - pain ().
The child with functional recurrent abdominal pain presents great
expectations about him/herself in several aspects (school, family,
and sports). He/she desires high patterns of performance, even already
having an adequate performance. Consequently, he/she gets frequently
frustrated, and this increases the risk for developing somatic manifestations
of stress ().
To sum up, children with functional recurrent abdominal pain do
not present accuracy in understanding the disease, but maintain
a limited control over it; they do not know the results of treatment
and prognosis; they present behavioral disorders and an elevated
level of anxiety and fear. These stressful factors predispose to
a change in the pain perception, making life become limited of low-quality,
and causing familial suffering.
Functional recurrent abdominal pain with
isolated paroxysms of periumbilical pain
In this type of functional recurrent abdominal pain, the episodes
of pain last for less than 1 hour in 50% of the children, and for
less than 3 hours in 40% of them. Time is longer in the remaining
cases. Pain varies in severity and frequency in the same patient.
The child indicates the umbilical region as the place where the
pain is more intense. There is no report of pain irradiation. Relationships
between the pain episodes and time, food, activities and intestinal
habits are rare. The paroxysms do not occur during sleep, but they
may prevent a child from sleeping. During the most intense crises,
associated signs and symptoms may occur: cephalea, paleness, nausea,
vertigo, prostration and mild fever (37.2 ºC to 37.7 ºC).
Motor signs for the relief of the pain are also observed, such as
bending the body over the abdomen, or compress it with the hands
(,,).
Between the crises, the child does not present complaints or alterations
on physical examination. In the retrospective history, reports of
colic, gastroesophageal reflux, anorexia, changes in milk formulas,
fear, sleep disorders, nocturnal enuresis, and difficulty in school
are common. In the familial history, reports of psychophysiological
symptoms and functional diseases, such as spastic bowel, irritable
bowel, mucosal or spastic colitis, as well as marital problems,
quarrels among brothers, recent diseases in relatives or other conflicts
are also frequent. When examining the patients' personality, we
find hyperactive, overdemaning patients, as well as those with intolerance
to frustration. They are "good children" in terms of attitudes,
behavior and maturity. They undertake more responsibility in relation
to the age group. They are aggressive with the adult's lack of sensibility
towards their disease, hardly tolerate criticism, and feel constant
fear (,,).
The causes of functional recurrent abdominal pain with isolated
paroxysms of periumbilical pain are listed in Table 1. A positive
diagnosis of functional presentation is carried out when the following
findings are present:
a) Onset of pain between 4 and 16 years of age;
b) Frequency of the process with at least three episodes of pain
in a period not inferior to 3 months;
c) Periumbilical pain crises without irradiation;
d) Normal physical examination, including rectal touch;
e) Factors that reinforce the painful behavior present in the environment;
f) Normal laboratory exams: hemogram, erythrocyte sedimentation
rate, urine routine and culture, parasitological examination of
feces, presence of blood in feces, abdominal simple radiography,
and ultrasound.
Table 1 - Causes of recurrent abdominal pain with isolated paroxysms
of periumbilical pain
The hemogram orientates about the presence of infections and hemolytic
anemias. An altered erythrocyte sedimentation rate points to inflammatory
diseases. Urine exams suggest infections or calculi. Parasitological
examination of feces should be performed due to the high prevalence
of parasites in our setting. The presence of blood in the feces
points to intestinal inflammatory diseases. Abdominal X ray and
ultrasound show the presence of renal and biliary calculi, anatomical
malformations, and mainly occult constipation. A diagnostic approach
of functional recurrent abdominal pain with isolated paroxysms of
periumbilical pain is shown in Figure 1.
Figure 1 - Algorithm for the diagnosis of functional recurrent abdominal
pain with isolated paroxysms of periumbilical pain
There are alert signs and symptoms that suggest the organic origin
of isolated paroxysms of abdominal pain, such as loss of weight,
impaired growth, pain distal from the umbilical region, pain that
awakes the child during the night, extraintestinal manifestations
(fever, skin eruptions, articular pain, recurrent aphthae, and dysuria),
presence of blood in feces, chronic diarrhea, anemia, elevated erythrocyte
sedimentation rate, and familial history suggestive of ulcerous
or inflammatory disease at the digestive tract (,).
The presence of these alterations, associated with other more specific
ones of organic causes, orient to the specific prognosis (Table
1).
The treatment of functional recurrent abdominal pain should emphasize
emotional factors through talks to the family, using a positive
approach while the problem is exposed. As the transition from the
organic to the functional focus occurs, the patient will feel relieved
of pain, and will not need further cognitive-behavioral interventions.
The first and most important step is the obtainment of a detailed
history. In order to achieve this objective, it is necessary to
let the family and the child talk; their bodies, their gestures,
their voices have to be observed. Group and individual interviews
with the parents and the child are essential components of this
process. Details about the pain, about the familial, social, and
school environment, and about familial and personal antecedents
are important in order to compose the diagnosis. The pediatrician
should try to identify why the seek for medical care happened at
that exact moment of such a chronic process as recurrent abdominal
pain, why the parents, and eventually the child, elected that specific
episode of pain to set an appointment. Still, the pediatrician should
value each episode of pain as being acute, considering that a child
with recurrent abdominal pain is not free from developing an acute
disease, such as appendicitis, for example. The treatment of functional
recurrent abdominal pain, which starts at the first appointment,
aims to:
a) clarify to the parents the authenticity of the pain. It is not
a case of simulation or imagination, but real pain.
b) Introduce the concept of functional disease.
c) Explain the possible role of alteration in the digestive tract
motility and of the visceral sensitivity in the genesis of the pain.
d) Orient about the relation between central nervous system, motility,
and intestinal sensitivity. The painful behavior should be explained
by the perspective of a social learnship.
e) Show the benignity of functional recurrent abdominal pain.
f) Tranquilize relatives and the child about the possibility of
serious organic diseases.
g) Introduce the concept of causative factors in the onset of crises
in functional diseases.
h) Diagnose the possible factors of the child's behavior that cause
or aggravate the pain status.
i) Condemn secondary benefits of the recurrent pain, such as gifts,
privileges, and more familial attention.
j) Advice the parents so that they ignore the nonverbal painful
behavior, and direct the child to some other activity when there
is a verbal communication of the pain. If the child agrees, he/she
should receive compliments, and possible new complaints should be
ignored. The parental care will be firm and discrete. The pain crises
should not subvert the familial dynamics.
k) The patient's life should be normal. The activities should only
be interrupted at the moment of the crisis. This is valid both in
the familial and in the social and school environment. After the
crisis, life has to go on. Behavioral effort will be made during
the days without pain. They will be registered, for example, in
a calendar, and for a given number of days in the week without painful
behavior, a reward can be given to the child. This procedure will
be periodically reviewed during the entire treatment, aiming at
increasing the number of days free from pain for new rewards. The
use of a scale to evaluate the intensity of the pain, such as the
color scale, allows the patient to verify his/her progresses objectively.
l) Teach the patient techniques that decrease the intensity of
the pain during the crises, deviating the attention from the pain
perception. Examples are whistling, singing, jumping, running, clicking
fingers, counting or making mathematical calculations mentally.
Relaxation techniques should be also taught aiming at decreasing
the pain, such as sitting, writing, walking, and lying in a pleasant
position. If the crises do not improve, the self reinforcement,
with positive self-verbalization, may be used. If the pain still
persists, imaginative strategies should be used: for example, the
pain is being destroyed by a hero, or the patient imagines he/she
is in pleasant situations.
m) Clarify what the alert signs are, showing the importance of
the immediate communication with the doctor when such signs are
observed (,).
These procedures aim at decreasing both the parents' and the patient's
anxiety, and mainly at condemning behaviors and situations that
cause, maintain or intensify the pain perception (,).
A study using these procedures showed that 87% of the children were
free from the pain within 3 months. In a control group, where the
conventional treatment was performed, only 37.5% of the patients
remained asymptomatic ().
The child should attend periodical appointments, mainly during
the first 6 months, so that the concepts of functional recurrent
abdominal pain, as well as the ways to handle the pain, are reinforced
and clarified. In these appointments, it is possible to verify if
the secondary benefits, causative factors, alert signs and symptoms,
as well as other findings that suggest organic disease are still
present. So, it consists of an active observation of the patient,
his/her family and setting.
The psychiatric treatment is only indicated when the child internalizes
the painful behavior in an extreme way (depression, anxiety, and
low self-esteem, or when conversion symptoms are verified), when
he/she is not able to take a normal life even after the harmful
factors are no longer present, or when the family is not able to
handle the painful process ().
The continuous use of drugs (anticholinergic, antispasmodic, anticonvulsant)
in the treatment of functional recurrent abdominal pain has not
proven benefic; on the contrary, it has shown to maintain the painful
process. The use of drugs in children with functional recurrent
abdominal pain intensify the hypochondriac state and the drug dependence
().
One only randomized, double-blind, placebo-controlled study showed
a reduction of 50% in the pain crises after the inclusion of fibers
in these children's diet ().
These results were not published. Sometimes, the decrease of sugars
(lactose, fructose, sorbitol, and amide) in the diet shows some
improvement in the crises (,,).
The fermentation of carbohydrates probably produces the gas that
distends the hypersensitive intestine, causing pain or increasing
the osmolality of the alimentary bolus that would alter the intestinal
motility.
Functional recurrent abdominal pain
with dyspepsia
The manifestation of dyspepsia is defined as a recurrent or persistent
pain, or as a discomfort that happens at the superior part of the
abdomen, and is caused by functional or organic diseases (reflux,
peptic disease, Crohn's disease). The functional diseases present
manifestations similar to the peptic ulcer or to the intestinal
motility alterations. In the ulcerous pattern, the epigastric pain
predominates; it precedes alimentation and is alleviated by foods
and antacids. In motility alterations, pain is not the main symptom.
Regurgitation, vomits, nausea, early satiety, and abdominal discomfort
occur. However, there are considerable variations and overlapping
of signs and symptoms among the groups ().
The functional recurrent abdominal pain with dyspepsia is influenced
by the same environmental and behavioral factors as the isolated
paroxysms of periumbilical pain. Thee are no signs or symptoms that
may distinguish between organic and functional dyspepsia. The diagnosis
should be done only when there is a characteristic history of recurrent
pain with normal physical examination (except for some pain at the
palpation of the superior part of the abdomen), and unaltered complementary
examinations: hemogram, erythrocyte sedimentation rate, serum amylase
and lipase, aminotransferases, H. pylori, parasitological examination
of feces, radiological contrast studies of the esophagus, stomach,
duodenum, and intestine, abdominal ultrasound, and upper gastrointestinal
endoscopy ().
The alert signs and symptoms for the organic causes are epigastric
pain, which expands to the back, blood in feces or in vomits, loss
of weight, fever, persistent vomits, diarrhea, dysphagia, hepatomegaly,
splenomegaly, abdominal mass or massiveness, and articular edema
(Table 2).
Table 2 - Causes of recurrent abdominal pain with dyspepsia
The treatment of functional recurrent abdominal pain with dyspepsia
is based on the orientation of the patient and parents about the
authenticity of the pain, concepts of functional pain, factors that
maintain, intensify, and improve the painful process, and prognosis
of the disease. This approach is discussed in the functional recurrent
abdominal pain with isolated paroxysms of periumbilical pain.
Adults with functional dyspepsias are sometimes treated with drugs.
Those that present ulcerous pattern receive histamine-2 receptor
antagonists, and are recommended not to smoke, not to use caffeine,
nonsteroidal anti-inflammatory drugs, and acetylsalicylic acid.
Those that present signs and symptoms suggestive of altered motility
are treated with prokinetics (cisapride or metoclopramide). There
are no data that prove the benefit of these interventions in children
with functional recurrent abdominal pain and dyspepsia. The use
of drugs reinforces the painful behavior ().
Functional recurrent abdominal pain
with digestive tract dysfunction
Recurrent abdominal pain with intestinal dysfunction is characterized
by pain usually at the inferior part of the abdomen, which is intensified
or alleviated with intestinal movements. With defecation, there
is the relief of pain, or its association with changes in the frequency
or consistency of the feces, feeling of incomplete defecation, evacuative
urgency or effort, passage of mucus, discomfort, and abdominal distension
().
The most frequent cause of recurrent abdominal pain with dysfunction
of the digestive tract is the functional irritable bowel syndrome,
which corresponds to the irritable bowel in the adult. It affects
mainly teenagers, and is manifested in two different ways, with
the predominance of diarrhea or constipation and with variable defecation
patterns. The diagnosis is done through typical history (recurrent
abdominal pain with intestinal dysfunction pattern), normal physical
examination, including rectal touch and laboratory tests without
alterations: hemogram, erythrocyte sedimentation rate, assay for
the detection of parasites, eggs, cysts, and occult blood in the
feces ().
The alert signs and symptoms suggestive of organic diseases are
pain or diarrhea that interrupt the sleep, presence of blood in
the feces, delayed growth, fever, skin eruptions, articular pain
or edema, fistula, perianal fissures or ulcers. The causes of recurrent
abdominal pain with digestive tract dysfunction are listed in Table
3.
Table 3 - Causes of recurrent abdominal pain with altered intestinal
pattern
The treatment of functional irritable bowel syndrome follows the
same orientations as the functional recurrent abdominal pain with
isolated paroxysms of periumbilical pain. Orientation should be
given to the parents and the patient about the authenticity of the
pain, the concept of functional pain, the factors that maintain,
intensify, and attenuate the pain crisis, and orientation about
the prognosis. However, patients in which diarrhea predominates
benefit from the use of antidiarrheal agents. Children that present
a tendency to constipation improve with the use of prokinetics and
fibers. The excessive use of carbohydrates should be avoided due
to the production of gases, and there should be orientation about
how to eat slowly, avoiding aerophagia. In some children, the use
of simeticone is recommended ().
Prognosis of functional recurrent abdominal
pain
Some retrospective studies and few prospective ones have assessed
the evolution of functional recurrent abdominal pain in childhood.
Two months after the diagnosis, 30 to 50% of the affected children
no longer complain of recurrent abdominal pain. This occurs when
the parents and the patient accept the association between stress
and pain. Some (25%) continue to present painful symptoms for 5
years. From 30 to 50% of these children will have abdominal pain
still in adulthood, but in 70% of the cases, the pain does not interfere
with the activities. One-third of the children with functional recurrent
abdominal pain will develop other pains in adulthood: cephalea,
backache, and menstrual pain. Thirty percent of the adults with
irritable bowel syndrome reported its beginning in childhood. The
possibility of the children to develop organic diseases, such as
Chron's disease, is below 2% (,,).
The best prognosis for functional recurrent abdominal pain occurs:
in families without pain complaints; in girls; when the beginning
of the pain crises occurs after 6 years of age; when the treatment
is started within 6 months after the beginning of the painful process.
The worst diagnosis is observed: in families with painful manifestations;
in boys; when the beginning of the pain occurs before 6 years of
age; when the seek for treatment occurs late.
Conclusions
The ambiguity of attitudes that these pain crises provoke in most
doctors and families frequently induces to a overabundance of examinations.
The impropriety of such conduct is far known. In the review of medical
records of children hospitalized for the assessment of deficient
growth, those with organic problems had the diagnosis strongly suggested
by history and by physical examination. No exam had a positive value
without a specific indication of the clinical evaluation ().
When many exams are performed without following any criterion, besides
the discomfort and the costs generated, there are other reasons
that should lead us to be prudent in cases of children with recurrent
pain. There is the possibility of finding some false positive exams,
and of the patient being diagnosed and frequently treated for a
disease that actually does not exist. The failure in acknowledging
this was already playfully called Ulisses' syndrome, in allusion
to the Greek mythological hero: the unnecessary and uncritical use
of laboratory examinations, leading to long investigation journeys,
and making the child and his/her family go through an unnecessary,
expensive, and sometimes dangerous expedition, whose end is the
starting point ().
Achieving an equilibrium, knowing the measurement of things, not
loosing time, neither abolishing stages of the investigation and
treatment processes of recurrent abdominal pain should be the pediatrician's
objective when facing a child and his/her family with this problem.
The pediatrician should not be as a secure refuge, but as a compass,
knowing that the prognosis of functional recurrent abdominal pain
is good, that only 1/4 of the patients continue to present painful
symptoms after 5 years counting from the beginning of the pains.
Late organic complications in this group of children are rare. These
attitudes help the pediatrician navigate in these calm but unclear
waters ().
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