Pediatric Annals

Special Issue Article 

Difficulties in the Diagnosis and Management of Functional or Recurrent Abdominal Pain in Children

Roberto Gomez-Suarez, MD

Abstract

Recurrent abdominal pain is a frequent pathology seen in the pediatric gastroenterology practice. In fact, most children with abdominal pain symptoms have functional disorders of the gastrointestinal tract. A focused medical history, comprehensive physical examination, and minimal testing are often enough to establish the diagnosis. The presence of red flags such as rectal bleeding, bilious vomiting, fever, and arthralgia should alert providers as well as direct further diagnostic and therapeutic plans. When patients show no red flags after a complete physical examination, providing the family with information about the pathophysiology and explaining the psychosocial model of pain can help to decrease anxiety around the pain symptoms. This article discusses the challenges in diagnosing and managing abdominal pain in children. [Pediatr Ann. 2016;45(11):e388–e393.]

Abstract

Recurrent abdominal pain is a frequent pathology seen in the pediatric gastroenterology practice. In fact, most children with abdominal pain symptoms have functional disorders of the gastrointestinal tract. A focused medical history, comprehensive physical examination, and minimal testing are often enough to establish the diagnosis. The presence of red flags such as rectal bleeding, bilious vomiting, fever, and arthralgia should alert providers as well as direct further diagnostic and therapeutic plans. When patients show no red flags after a complete physical examination, providing the family with information about the pathophysiology and explaining the psychosocial model of pain can help to decrease anxiety around the pain symptoms. This article discusses the challenges in diagnosing and managing abdominal pain in children. [Pediatr Ann. 2016;45(11):e388–e393.]

Recurrent abdominal pain is one of the chief complaints in pediatric gastroenterology.1 However, it is reassuring to know that after a methodic clinical history, physical examination, minimal diagnostic testing, and thoughtful reassurance, the majority of the patients improve, especially when functional disorders are the cause. Abdominal pain can be secondary to celiac, Crohn's, gallbladder, or pancreatic disease. The presence of red flags helps clinicians determine a diagnosis. In patients with no red flags, the need for extensive testing is rarely necessary; a “million-dollar evaluation” frequently does not yield any useful information. In contrast, it can induce more parental anxiety.2

Functional Abdominal Pain

Functional abdominal pain is a frequent symptom in the pediatric patient; it accounts for approximately 3% to 4% of visits to primary care pediatricians, and 25% of visits to pediatric gastroenterologists.1 According to the Rome III criteria, functional gastrointestinal disorders are defined as the presence of abdominal pain at least once a week for at least 2 months.3 Complex factors, including the presence of comorbidities such as anxiety, school pressure, lack of coping skills, parental reinforcing factors, history of infectious processes, and dietary factors, can induce and perpetuate abdominal pain in children.4–7 Together, these factors constitute the “biopsychosocial model” for pain. The primary care visit should include (1) a complete history and physical examination to rule out red flags, (2) an in-depth discussion of parental concerns, coupled with education about reinforcing factors and coping skills, and (3) substantial reassurance; this is all essential to managing children with functional abdominal pain.

Pathophysiology

The pathophysiology of functional abdominal pain involves a distortion of the perception of visceral sensation that alters the brain-gut communication. In a healthy person, the interoceptive signaling from the viscera to the brain is usually not perceived; however, in patients with functional abdominal pain, the afferent signals traveling through the spinothalamic afferents to the somatosensory cortex are distorted and therefore perceived as pain in the abdomen. Because afferent signals travel in conjunction with autonomic pathways and project on different somatosensory areas, including the amygdala, it explains why these patients have multiple abnormal autonomic and behavioral responses associated with the perception of the pain. Central and peripheral sensitization also contribute to pain, and previous traumatic experiences or infections may also be a key factor.8,9

Red Flags and Diagnostic Clues

There are many organic causes of recurrent abdominal pain that may be classified according to the frequency of presentation and the localization of pain severity. The most common organic causes of chronic abdominal pain are listed in Table 1.


            Common Organic Causes of Chronic Abdominal Pain

Table 1.

Common Organic Causes of Chronic Abdominal Pain

For decades, diagnostic “red flags” have been used as clues to distinguish organic and functional disorders of the gastrointestinal tract. Recently, however, new data suggest that differentiating organic and functional abdominal pain based on a few clinical signs may be unreliable and that not all red flags are of equal diagnostic value.10

Perhaps the most valuable red flags are those that emerge from the patient's history and physical examination, in which diseases and conditions associated with abdominal pain that merit referral for medical or surgical evaluation and treatment are promptly recognized. For example, the presence of blood in the stool is commonly associated with intestinal inflammation, and necessitates an evaluation for infectious, inflammatory diseases or the presence of intestinal polyps. Anal fissures should lead to an assessment for Crohn's disease. Unexplained periodic fever is a worrisome sign that should prompt a referral for evaluation for inflammatory bowel disease, malignancy, and rheumatoid disorders. Unintentional weight loss is also concerning and should prompt evaluations for tuberculosis, rheumatoid disease, inflammatory bowel disease, celiac disease, and other types of inflammatory and infectious enteropathies. Frequent emesis, in particular bilious vomiting, suggests the presence of partial obstruction or intermittent intussusception. Constipation and abdominal distension are associated with strictures or narrowing of the large intestine; lymphoma can present as a mass palpable in the abdomen. The presence of right upper quadrant and epigastric pain warrants evaluation for gallbladder disease, peptic ulcer disease, gastritis (including Helicobacter pylori infection), and chronic pancreatitis. Hematuria, dysuria, and flank pain suggest pyelonephritis or ureteral obstruction.

During the physical examination, jaundice, pallor, a mass palpable in the abdomen, hepatomegaly, splenomegaly, and diffuse lymphadenopathy are worrisome signs suggestive of chronic conditions such as infections, autoinflammatory diseases, or malignancy. Rashes, especially vasculitic or purpuric rashes, suggest systemic vasculitis that can also involve the gastrointestinal tract. Patients with family histories of inflammatory bowel disease, celiac disease, H. pylori infection, polyposis, or pancreatitis should be examined carefully, recognizing that the prevalence rates of these diseases are increased in patients with family histories of these disorders.

Functional Abdominal Pain Disorders in Children and Adolescents

Functional gastrointestinal disorders are classified according to the Rome IV criteria that was recently articulated in a consensus statement for this condition.11 In short, the criteria indicate that patients with functional gastrointestinal disorders have recurrent symptoms not attributable to an inflammatory, neoplastic, or metabolic cause. Patients with functional gastrointestinal diseases lack the red flag signs and symptoms described above and have a normal physical examination.

The Most Common Conditions

Functional dyspepsia is described as the presence of upper abdominal discomfort or pain, early satiety, and postprandial fullness occurring at least weekly or 4 or more times per month.11 Pain and discomfort due to functional dyspepsia are not relieved by defecation.

Recently, two variants of functional dyspepsia were adopted from the adult literature.11,12 The first variant of functional dyspepsia—postprandial distress syndrome—presents with early satiety, bloating, belching, and postprandial nausea. The second variant of functional dyspepsia—epigastric pain syndrome—presents with an epigastric burning sensation without a retrosternal component. Neither postprandial distress syndrome nor epigastric pain syndrome is relieved with defecation.12

Irritable bowel syndrome is abdominal pain or discomfort that occurs at least 4 days per month.11 Pain is either related to defecation or associated with a change in the consistency or frequency of the stool.

Functional abdominal pain presents as episodic or continuous abdominal pain occurring at least 4 times per month.11 Functional abdominal pain does not occur in association with normal physiological events, such as menses, without other criteria for functional gastrointestinal disorders.

Childhood functional abdominal pain syndrome often occurs with other somatic symptoms, such as a headache, limb pain, or difficulty sleeping.11 In more than 25% of pediatric patients with functional abdominal pain, there is some loss of daily functioning.11

An abdominal migraine is defined as the occurrence of paroxysmal episodes of acute and intense periumbilical abdominal pain lasting for more than 1 hour. Abdominal migraine episodes are separated by periods of weeks to months of no symptoms. Pain in abdominal migraines interferes with normal activities and is associated with two or more of the following symptoms: anorexia, nausea, vomiting, headaches, photophobia, and pallor.11

Diagnostic Evaluation

The tests most commonly performed during the first clinic visit for evaluation of recurrent abdominal pain include a complete blood count, a serum metabolic panel, an erythrocyte sedimentation rate, a urinalysis, fecal occult blood and, in some selected cases, fecal calprotectin.13 Abdominal radiographs have a low yield, but may be helpful when masses or constipation are suspected. Abdominal ultrasonography is helpful when pain localizes to the right upper quadrant, when a mass is detected, or when kidney stones are suspected. If these studies are normal, then referral to a pediatric gastroenterologist for specialty studies (Table 2) should be considered.


            Specialty Studies and Procedures Ordered by a Pediatric Gastroenterologist

Table 2.

Specialty Studies and Procedures Ordered by a Pediatric Gastroenterologist

Management and Reassurance

In patients with functional abdominal pain, providing the parents with explanations that help them understand the pathophysiology of recurrent pain is a mainstay of therapy. Successfully providing reassurance requires adequate time during the clinic visit for parents to discuss their concerns. An important facet of the discussion about functional abdominal pain is establishing end goals that include modification of factors and behaviors that trigger and perpetuate abdominal pain, as well as those intended to increase resiliency and coping skills.

Diet and Nutrition

Appropriate dietary and nutritional counseling are important objectives of the clinic visit. An accurate recollection of the patient's diet should be documented in the medical record. Disease-specific dietary modifications can then be recommended. Particular attention should be paid to the types and quantities of carbohydrates in the recommended diet. For patients with irritable bowel syndrome and functional abdominal pain, the low FODMAPs (Fermentable Oligo-saccharides, Di-saccharides, Mono-saccharides And Polyols) diet has gained popularity. The low FODMAPs diet reduces the amount of dietary short-chain carbohydrates that induce gas production, leading to distention of the large intestine, bloating, and abdominal pain.19 For patients with functional abdominal pain, food components to avoid include: fructose-containing fruits and juices, honey, high fructose corn syrup, lactose and lactose-containing dairy products; fructans contained in wheat, onion, and garlic; galactans contained in beans, lentils, and legumes such as soy; polyols, such as sorbitol, mannitol, xylitol, and maltitol, which are often used as sweeteners; and stone fruits, such as avocado, apricots, cherries, nectarines, peaches, and plums. Wheat and other gluten-containing products should be excluded from the diets of patients with nonceliac gluten sensitivity.20

Medications and Pharmacology

Several medications have been used in treating chronic abdominal pain. The decision to prescribe medication to a patient with abdominal pain should be individualized, and the side-effect profile of all medications should be discussed. The most common medication categories used include antiacids, antisecretory, antispasmodics, antidepressants (tricyclic antidepressant amitriptyline), antihistamines, and anticonvulsants. Antispasmodics (including peppermint oil) are also used commonly in these patients; during a short course, less than 8 weeks, their efficacy is superior to placebo.21 The side effects of antispasmodic therapies include constipation and urinary retention. In a trial, the use of citalopram led to modest clinical improvement over the placebo.22 Despite evidence supporting the use of tricyclic antidepressants for treatment of functional abdominal pain, the efficacy of tricyclic antidepressant therapy is only modestly better than placebo, 63% versus 47%;23 behavioral changes and suicidal ideation are possible side effects. Cyproheptadine, an antihistamine, is often prescribed as an effective treatment for functional abdominal pain;24,25 side effects include sedation and weight gain.

There are reports that holistic and psychological therapies have roughly the same rates of improvements as medications.26 Parents should be aware that there is a high probability that the patient will improve without medication, as evidenced by the substantial placebo effect found in the management of functional abdominal pain (the placebo effect alone may account for 9%–53% of patient improvement).27

Psychological Intervention

Studies have found that the use of psychological therapies, such as gut-induced hypnotherapy, cognitive-behavioral therapy, hypnotherapy, and visual imagery, may be superior to standard pharmacological therapies for treatment of functional abdominal disease.28–30

Prognosis

In general, chronic abdominal pain improves in 15% to 25% of patients.31 A proportion of patients develop other functional syndromes such as irritable bowel syndrome.6 The presence of perpetuating factors, including dysfunctional families, the presence of comorbidities, and family reinforcing behaviors, contribute to the persistence of recurrent abdominal issues.32

Concluding Thoughts

Recurrent abdominal pain is frequently seen in the pediatric primary care and gastroenterology practice. Although a detailed history and physical examination are enough to make a diagnosis in most cases, careful attention is necessary to exclude red flag signs. Pain management should be individualized, and multiple therapeutic resources are available.

References

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Common Organic Causes of Chronic Abdominal Pain

Pain Presentation Condition Red Flag Diagnostic Test
Esophagus
Esophagitis Peptic, eosinophilic Dysphagia, heartburn EGD
Esophageal dysmotility Spasm, achalasia Dysphagia, heartburn Esophageal manometry
Stomach
Peptic Helicobacter pylori, NSAIDs gastropathy, IBD Anemia, positive FOB Stool H. pylori, EGD
Malrotation Volvulus Bilious vomiting UGI
IBD motility Gastroparesis Delayed vomiting GES
Small bowel colon
Other enteritis HS purpura, NSAIDs gastropathy Vasculitic rash Clinical/EGD
Parasitic Giardia, strongyloides Diarrhea, bloating Stool giardia ELISA
Malabsorption Celiac disease Diarrhea, weight loss, anemia, constipation TTG IgA, IgA total
SB obstructive Intussusception, Meckel's diverticulum Bilious vomiting US, Meckel's diverticulum, CT
IBD Strictures Weight loss, vomiting MRE, endoscopy, CT
Epiploic appendagitis Inflammatory Severe pain crisis CT
Colonic obstructive Stricture, polyps masses Anemia, weight loss, vomiting CT, MRE, endoscopy
Liver/gallbladder pancreas
Obstructive disorder Gallstones, choledochal cyst, hepatitis Jaundice, RUQ pain US, transaminitis, cholestasis
Functional disorder Gallbladder, dyskinesia RUQ pain HIDA scan
Pancreatitis Acute recurrent, chronic Vomiting, weight loss CT, elevated lipase
Genitourinary/gynecological
Obstructive disorder Hydroneprosis, urolithiasis Hematuria, back pain UA, US, CT
Inflammatory disorder UTI Fever, hematuria UA, UCX
Anatomic disorder Renal cyst Hematuria, back pain UA, US, CT
Dysfunctional disorder Dysmenorrhea Menstrual cycle abnormalities Clinical
Anatomical disorder Ovarian cyst, endometriosis Menstrual cycle abnormalities US, laparoscopy
Other conditions
Malignancy Lymphoma Constipation, vomiting, weight loss US, CT
Abdominal wall ACNES, hernia Reproducibility with pressure Clinical
Metabolic disorder Porphyria Seizures, dehydration Urine coproporphyrine
Allergic/immune Angioedema, circumferential jejunitis Vomiting, weight loss CT, MR, UGI

Specialty Studies and Procedures Ordered by a Pediatric Gastroenterologist

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Celiac antibodies in patients at risk for gluten enteropathy.14,15 In children, abdominal pain and chronic diarrhea are the most common symptoms of nonceliac gluten enteropathy16

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Upper endoscopy for patients with epigastric pain, heartburn, vomiting, or hematemesis, or when inflammatory bowel disease is suspected

</list-item><list-item>

Colonoscopy for patients suspected of having inflammatory bowel disease because of weight loss, fevers, chronic diarrhea, or blood or mucous in the stool

</list-item><list-item>

HIDA scan in patients with right upper quadrant abdominal pain in whom biliary dyskinesia is suspected17

</list-item><list-item>

Glucose or lactulose breath test when bacterial overgrowth is suspected in patients with irritable bowel syndrome18

</list-item>
Authors

Roberto Gomez-Suarez, MD, is a Pediatric Gastroenterology Attending, Nemours Children's Hospital; and an Assistant Professor of Pediatrics, University of Central Florida College of Medicine.

Address correspondence to Roberto Gomez-Suarez, MD, 13535 Nemours Parkway, Orlando, FL 32827; email: roberto.gomezsuarez@nemours.org.

Disclosure: The author has no relevant financial relationships to disclose.

10.3928/19382359-20161019-01

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