Recurrent Abdominal Pain Syndrome

1. Definition
   1. Pain occurs at least once/month for at least 3 months
   2. Ages 5 - 16 years (peaks at age 9 years)
   3. Affects activity, school attendance
2. Epidemiology
   1. Prevelance
      1. School age children: 10-15%
      2. Pre-teen and teenage children: 20%
3. Pathophysiology
   1. Autonomic Dysfunction with altered intestinal motility
   2. Hyperalgesia and altered sensory pathways
4. Causes
   1. Functional Abdominal Pain in most cases
      1. Dyspepsia
      2. Irritable Bowel Syndrome
      3. Abdominal Migraine
      4. Functional Constipation
      5. Cyclical Vomiting
      6. Adolescent Rumination Syndrome
   2. Organic cause in 3-8% of cases (see differential diagnosis below)
      1. See Abdominal Pain Causes
5. Risk Factors
   1. School Phobia (and related stresses) closely associated
   2. Parents (especially mothers) often have Anxiety Disorder or Major Depression
6. Associated Conditions
   1. Anorexia Nervosa
7. Symptoms
   1. Nonspecific recurrent Abdominal Pain
      1. Typically periumbilical or epigastric, ill-defined pain
      2. Not related to meals
      3. Not related to movement or activity
   2. Nausea or Vomiting may be present depending on type
   3. No Dysuria
8. Signs
   1. Well appearing child
   2. Exam is often normal or mild abdominal tenderness
   3. Normal growth curves (or Body Mass Index for age)
9. Signs: Red flags
   1. Pain location distant from Umbilicus
   2. Pain that awakens child at night
   3. Erythrocyte Sedimentation Rate (ESR) or C-Reactive Protein (C-RP) elevated
   4. Weight loss
   5. Blood in stool
10. Labs (Limited and focused work-up)
    1. Stool for Ova and Parasites for 3 samples
       1. Giardia is common cause of recurrent Abdominal Pain
    2. Urinalysis
    3. Complete Blood Count (CBC)
    4. Erythrocyte Sedimentation Rate (ESR)
    5. C-Reactive Protein
11. Imaging
    1. Flat and upright abdominal XRay (KUB)
    2. Consider RUQ Ultrasound
    3. Consider pelvic Ultrasound
12. Differential Diagnosis
    1. Crohn's Disease
    2. Peptic Ulcer Disease
    3. Carbohydrate intolerance
    4. Appendiceal colic
    5. Nephrolithiasis (Ureteropelvic junction obstruction)
    6. Giardia
    7. Blastocystis hominis
    8. Hereditary Pancreatitis
    9. Abdominal Migraine
    10. Epilepsy
    11. Gynecologic disorder
    12. Psychiatric disorder or abuse
        1. Major Depression
        2. Generalized Anxiety Disorder
        3. Sexual Abuse
        4. Physical abuse
        5. Conversion reaction
13. Management
    1. Avoid Medications
       1. Peppermint Oil capsule three times daily has been used
    2. Emphasize the patient's response to pain
    3. Involve the parents
    4. Reassure that the problem is NOT life threatening
    5. Be realistic and frank
       1. Problem may persist for extended period of time
    6. Treat suspected Constipation aggressively
       1. Mineral Oil
       2. Lactulose
       3. Fleet Enema
    7. Promote full activity and a sense of health
    8. Encourage a well balanced diet
    9. Encourage adequate hydration
    10. Encourage adequate fiber intake
    11. Maintain school attendance
14. Course
    1. Usually resolves by age 20 years
    2. Irritable Bowel Syndrome may develop
15. Prognosis
    1. These children often get lower grades than peers
16. References
    1. Thiessen (2002) Pediatr Rev 23(2):39-46
    2. Claudius in Majoewsky (2012) EM:RAP-C3 2(3): 3