DR. KANUPRIYA CHATURVEDI 1 1.TERMINOLOGY AND DEFINITION 2.EPIDEMILOGY & ETIOLOGY PATHOPHYSIOLOGY 3.EVALUATION AND DIAGNOSIS 4.MANAGEMENT 5.PROGNOSIS 6. SUMMARY 2 Chronic and recurrent abdominal pain are common symptoms in children and adolescents . Chronic abdominal pain can be organic or nonorganic, depending on whether a specific etiology is identified. Nonorganic abdominal pain or functional abdominal pain refers to pain without evidence of anatomic, inflammatory, metabolic, or neoplastic abnormalities. Overlap between chronic and recurrent abdominal pain exists, and the terms are sometimes used synonymously. SOURCE: J.APLEY 3 Chronic abdominal pain — Chronic abdominal pain is defined by pain of at least three months' duration, although some clinicians consider pain of more than one to two months' duration to be chronic . Recurrent abdominal pain — Recurrent abdominal pain is one of the most common recurrent pain syndromes in childhood. The classic definition is based upon four criteria : ◦ ◦ ◦ ◦ History of at least three episodes of pain Pain sufficiently severe to affect activities Episodes occur over a period of three months No known organic cause Source:Hyams et.al 1996. 4 Chronic abdominal pain ◦ Long-lasting intermittent or constant abdominal pain that is functional or organic (disease based) Functional abdominal pain ◦ Abdominal pain without demonstrable evidence of pathologic condition, such as anatomic metabolic, infectious, inflammatory or neoplastic disorder. Functional abdominal pain can manifest with symptoms typical of functional dyspepsia, irritable bowel syndrome, abdominal migraine or functional abdominal pain syndrome. Functional dyspepsia ◦ Functional abdominal pain or discomfort in the upper abdomen 5 Irritable bowel syndrome ◦ Functional abdominal pain associated with alteration in bowel movements Abdominal migraine ◦ Functional abdominal pain with features of migraine (paroxysmal abdominal pain associated with anorexia, nausea, vomiting or pallor as well as maternal history of migraine headaches) Functional abdominal pain syndrome ◦ Functional abdominal pain without the characteristics of dyspepsia, irritable bowel syndrome, or abdominal migraine. 6 The American Academy of Pediatrics (AAP) and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) guidelines for the evaluation and treatment of children with chronic abdominal pain recommend that the term "recurrent abdominal pain" should not be used as a synonym for functional, psychological, or stress-related abdominal pain . As discussed below, functional abdominal pain, which is the most common cause of chronic abdominal pain, is a specific diagnosis that must be distinguished from other causes of abdominal pain (eg, anatomic, infectious, inflammatory, metabolic) source: American Academy of Paed.2005 7 Functional gastrointestinal disorders (FGIDs) are a group of gastrointestinal (GI) disorders that include variable combinations of chronic or recurrent GI symptoms not explained by structural or biochemical abnormalities. The Rome Committee updates and modifies the information on FGIDs for clinical and research purposes 8 The term is used in gastroenterology if no specific structural, infectious, inflammatory, or biochemical cause for the abdominal pain can be determined. Because the exact etiology and pathogenesis of the pain are unknown and because no specific diagnostic markers exist, a diagnosis of functional bowel disorder often is viewed as a diagnosis of exclusion. The diagnosis is established by a constellation of criteria based on a careful history, physical examination, and minimum laboratory investigation. 9 Diagnostic criteria must include all of the following: ◦ Episodic or continuous abdominal pain ◦ Insufficient criteria for other FGIDs ◦ No evidence of an inflammatory, anatomic, metabolic or neoplastic process that explains the subject's symptoms 10 Diagnostic criteria satisfy criteria for childhood functional abdominal pain and have at least 25% of the time one or more of the following ◦ Some loss of daily function ◦ Additional somatic symptoms such as headache, limb pain, or difficulty sleeping 11 H1 H2b H1a H2c ◦ Adolescent rumination syndrome H2d ◦ Cyclic vomiting syndrome H1c H2d1 H2 Abdominal pain—–related FGIDs H2a H3 H3a H3b ◦ Vomiting and aerophagia H1b ◦ Aerophgia ◦ Functional dyspepsia ◦ Irritable bowel syndrome ◦ Abdominal migraine ◦ Childhood functional abdominal pain ◦ Childhood functional abdominal pain syndrome ◦ Constipation and incontinence ◦ Functional constipation ◦ Nonr-Retentive fecal incontinence 12 The exact incidence and prevalence of chronic abdominal pain is not known. There are reports of chronic abdominal pain affecting 9-15% of children. There are also reports that 13% of middle school and 17% of high school children have weekly complaints of abdominal pain. In a study of 1,000 school-age children, RAP affected males & females equally up to 9 yrs. of age, the incidence in females increased such that between 9 & 12 yrs., the female-to-male ratio was 1.5:1. 13 The traditional concept that motility disorders alone have an important role in functional pain has not been confirmed. It is believed that visceral hypersensitivity leading to abnormal bowel sensitivity to stimuli (physiologic, psychologic, noxious) might have a more dominant role in functional abdominal pain . 14 The viscera are innervated by dual set of nerves (vagal and splanchnic spinal nerves or pelvic and splanchnic spinal nerves). The spinal afferents carry impulses to the spinal cord. The dorsal horn of the spinal cord regulates conduction of impulses from peripheral nociceptive receptors to the spinal cord and brain, and the pain experience is further influenced by cognitive and emotional centers. 15 A normal functioning enteric nervous system (ENS) is important for coordination of intestinal motility, secretion and blood flow. Abnormalities of the enteric nervous system may be an underlying factor for functional abdominal pain . Inflammation of the intestine and its role in the pathogenesis of functional abdominal pain could be due to the effects of the inflammatory mediators and cytokines (released by the various inflammatory cells) on the ENS. 16 17 18 Children who have RAP tend to exhibit one of three clinical presentations: ◦ Isolated paroxysmal abdominal pain ◦ Abdominal pain associated with symptoms of dyspepsia ◦ Abdominal pain associated with an altered bowel pattern. 19 Symptoms of dyspepsia include: ◦ pain associated with eating; epigastric location of pain; nausea, vomiting, heartburn, oral regurgitation, early satiety, excessive hiccups and belching. Symptoms of altered bowel pattern include: ◦ diarrhea, constipation, or a sense of incomplete evacuation. Functional abdominal pain is by far the most common cause of each presentation. 20 21 The American Academy of Pediatrics (AAP) and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) guidelines for the evaluation and treatment of children with chronic abdominal pain recommend history, physical examination, and stool testing for occult blood to identify potential indications of an organic etiology. The technical review found little or no evidence to suggest that ultrasonography, endoscopy, or esophageal pH monitoring increase the yield of organic disease in the absence of "alarm findings”. 22 The history provides important clues to the etiology of abdominal pain and must assess possible organic causes for the pain, as well as psychosocial factors that may be contributing to it . The older child or adolescent should be encouraged to provide his or her own description of the pain. source: Ramchandani 2005 23 Visceral pain is dull and aching in character and often poorly localized. It arises from distention or spasm of a hollow organ, such as the discomfort experienced early in intestinal obstruction or cholecystitis. Parietal pain is sharp and very well localized. It arises from peritoneal irritation, such as the pain of acute appendicitis with spread of inflammation to the parietal peritoneum. Referred pain is aching and perceived to be near the surface of the body. 24 The location of abdominal pain helps to narrow the differential diagnosis . Pain caused by esophagitis and peptic ulcer disease usually causes discomfort in the upper abdomen. The location of pain related to hypercalciuria and/or hyperuricosuria appears to vary with age. Pain radiation also is important: the pain of pancreatitis classically bores to the back, whereas renal colic radiates to the groin. source: Polito et al 2005 25 The onset, frequency, and duration of the pain are helpful features. Pain that began at the start of the school year and never occurs on weekends is unlikely to have an organic cause. The quality of the pain includes determining whether the pain is burning or gnawing, as is typical of gastroesophageal reflux and peptic ulcer, or colicky, as in the cramping pain of gastroenteritis or intestinal or biliary obstruction. 26 The severity of the pain typically is related to the severity of the disorder. However, this distinction often is difficult for the clinician to evaluate because it is subjective and dependent upon the patient's personality and previous pain experiences A helpful approach is to ask the child or adolescent to compare this pain with previous painful experiences, grading on a 1 to 10 scale. The child should be asked whether pain disrupts sleep or usual activities or has caused any school absence. 27 Asking the patient for factors that can aggravate or alleviate the pain is also important. The pain of mesenteric ischemia usually starts within one hour of eating, whereas the pain of peptic ulcer disease is relieved by eating and recurs several hours after a meal, when the stomach is empty. Symptoms that occur in relation to abdominal pain may give important information. Weight loss may occur in association with malignancy, nausea and vomiting with bowel obstruction, and change in bowel habits with a colonic lesion. 28 Physical examination — A complete physical examination with emphasis on the abdominal, rectal, pelvic, and genitourinary regions is an essential part of the evaluation of the child and adolescent with abdominal pain. General — The general appearance and level of comfort or discomfort should be noted. The patient's weight (percentile or percent ideal body weight), height, growth velocity, pubertal stage, and blood pressure should be noted. 29 Abdominal — Inspection of the abdomen should include attention to the position assumed by the patient when in pain. Gentle percussion is useful to identify acute peritonitis. It is also used to identify ascites, liver span, and splenic enlargement. Tympany signifies a distended bowel, whereas dullness may signify a mass. 30 Palpation must be performed gently and while the patient is distracted, particularly if psychogenic pain is suspected. Muscular rigidity or "guarding" is an important and early sign of peritoneal inflammation; it can be unilateral in a patient with a focal inflammatory mass, such as a diverticular abscess, or diffuse, as in peritonitis. Guarding typically is absent with deeper sources of pain, such as renal colic and pancreatitis. t. Palpation also may detect enlarged organs or masses (eg, fecal material in the left lower quadrant). 31 Carnett sign is helpful in distinguishing deep visceral pain from pain that emanates from the abdominal wall . Carnett sign is positive (indicating abdominal wall pain) if the focal tenderness increases or remains during abdominal muscle contraction. Abdominal wall pain can originate from a hernia, hematoma, or the abdominal wall musculature. source: Thompson et al 1991 32 Rectal and pelvic — Perianal and rectal examination and stool testing for occult blood are required in the evaluation of all patients. In addition, a pelvic examination should be performed if the history is suspicious for gynecological problems. A pelvic ultrasound or a referral to a pediatric gynecologist or adolescent medicine specialist can be helpful. 33 Other findings — The patient should be examined for signs of nerve and muscle wall injury and hernia. Pain in a dermatomal distribution and hyperesthesia are both signs of nerve involvement. Pain that is reproduced with hyperextension at the hip (psoas sign) suggests inflammation of the psoas muscle. 34 Indications — The American Academy of Pediatrics (AAP) and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) guidelines for the evaluation and treatment of children with chronic abdominal pain recommend stool testing for occult blood to identify potential indications of an organic etiology. Initial studies are performed to confirm or exclude diagnostic possibilities that are being considered based upon the history and physical examination. The results of initial studies can help determine the urgency and pace of the diagnostic evaluation. 35 Pain that wakes up the child from sleep Persistent right upper or right lower quadrant pain Significant vomiting (bilious vomiting, protracted vomiting, cyclical vomiting or worrisome pattern to the physician) Unexplained fever Genitourinary tract symptoms Dysphagia Chronic severe diarrhea or nocturnal diarrhea Gastrointestinal blood loss Involuntary weight loss Deceleration of linear growth Delayed puberty Family history of inflammatory bowel disease, celiac disease, and peptic ulcer disease 36 Localized tenderness in the right upper quadrant Localized tenderness in the right lower quadrant Localized fullness or mass Hepatomegaly Splenomegaly Jaundice Costovertebral angle tenderness Arthritis Spinal tenderness Perianal disease Abnormal or unexplained physical findings 37 Laboratory studies may be unnecessary if the history and physical examination lead to a diagnosis of functional abdominal pain. Nonetheless, medical tests can reassure the patient and family, and at times the physician, if there is significant functional disability and poor quality of life. 38 A complete blood cell count, sedimentation rate, C-reactive protein, basic chemistry panel, celiac panel, stool culture, stool test for ova and parasites, and urinalysis are reasonable screening studies. The risk of celiac disease may be 4 times higher in these patients compared with the general population. Elevated stool calprotectin levels usually suggest an inflammatory etiology. 39 If indicated, an ultrasound examination of the abdomen can give information about kidneys, gallbladder, and pancreas; with lower abdominal pain, a pelvic ultrasonogram may be indicated An upper GI x-ray series is indicated if one suspects a disorder of the stomach or small intestine. Helicobacter pylori infection does not seem to be associated with chronic abdominal pain, but in patients with symptoms suggesting gastritis or ulcer, an H. pylori test (fecal H. pylori antigen) may be performed. 40 Breath hydrogen testing is done for ruling out lactose or sucrose malabsorption. Lactose intolerance is so common that the finding may be coincidental, and the clinician must be cautious in attributing chronic abdominal pain to this condition. Esophagogastro-duodenoscopy is indicated with symptoms suggesting persistent upper GI pathology. . 41 The two broad categories in the differential diagnosis for chronic or recurrent abdominal pain in children and adolescents are ◦ Organic disorders — Conditions in which physiologic, structural, or biochemical abnormalities are present. ◦ Functional disorders — Functional conditions are those for which no specific test exists with which to make the diagnosis 42 Common organic causes of chronic or recurrent abdominal pain include constipation, carbohydrate malabsorption, musculoskeletal pain, parasitic infection, dysmenorrhea, and peptic disorders (eg, reflux esophagitis, gastritis, gastric and duodenal ulcers, and ◦ H. pylori infection. ◦ ◦ ◦ ◦ ◦ ◦ Dern M.S 1999 43 ◦ Less common causes include: Urinary tract infections, inflammatory bowel disease, endometriosis, and pelvic inflammatory disease. Other, rare causes must also be considered; they include gallstones , kidney stones , late presentation of malrotation or volvulus , heavy metal poisoning , psoas abscess, meconium ileus equivalent, imperforate hymen with hematocolpos , ovarian neoplasm ,remote pancreatic injury, familial Mediterranean fever , hypercalciuria , tuberculosis , and hereditary angioedema . 44 Historical or physical examination findings usually provide clues to the diagnosis in the cases in which an organic etiology is identified: ◦ Pain distant from the umbilicus ◦ Pain that awakens the child or adolescent ◦ Significant vomiting (bilious, protracted, cyclical, or an otherwise worrisome pattern) ◦ Dysphagia ◦ Respiratory symptoms Family history of inflammatory bowel disease, celiac disease, peptic ulcer disease, or kidney stones Involuntary weight loss, slowed linear growth, or delayed puberty Joint pain or swelling Unexplained fever Changes in bowel or bladder function 45 Dysuria or hematuria Chronic severe diarrhea, nocturnal diarrhea, or excessive gas Persistent right upper or right lower quadrant pain or tenderness Localized fullness or mass effect Hepatomegaly Splenomegaly Tenderness over the spine or at the costovertebral angle Perianal abnormalities Other abnormal, unexplained physical examination findings ◦ Anemia ◦ Gastrointestinal blood loss ◦ Elevated erythrocyte sedimentation rate 46 Functional disorders — Functional disorders are conditions in which the patient has a variable combination of symptoms without any readily identifiable structural or biochemical abnormality. Several functional gastrointestinal disorders of childhood are recognizable . ◦ ◦ ◦ ◦ ◦ Functional dyspepsia Irritable bowel syndrome (IBS) Functional abdominal pain Abdominal migraine Aerophagia 47 Dyspepsia is pain or discomfort that is centered in the upper abdomen. Discomfort may be characterized by fullness, early satiety, bloating, nausea, retching, or vomiting . Functional dyspepsia symptoms may be ulcer-like, with pain centered in the upper abdomen as the predominant symptom, or dysmotility-like, with discomfort (eg, fullness, early satiety, bloating, or nausea) centered in the upper abdomen as the predominant symptom. Organic causes of dyspepsia symptoms include acidrelated disease (esophagitis, gastritis, duodenitis), H. pylori, eosinophilic esophagitis, eosinophilic gastroenteritis, Crohn's disease, and celiac disease. 48 The pathophysiology of functional dyspepsia is not clear. Abnormalities in gastric electrical rhythm, delayed gastric emptying, reduced gastric volume response to feeding, and antroduodenal dysmotility have been demonstrated in some children and adolescents . Abnormal motor function, visceral sensitivity, and psychosocial factors have been studied as possible contributing factors in adults. source:Cucchiara S,et al, 1992 49 No signs or symptoms reliably differentiate functional dyspepsia from upper gastrointestinal inflammatory, structural, or motility disorders. Symptoms of dyspepsia usually generate a more extensive diagnostic evaluation . 50 IBS is characterized by chronic abdominal pain and altered bowel habits in the absence of any organic cause. Organic causes that should be considered include Giardia, urinary tract infection, carbohydrate intolerance, inflammatory bowel disease, eosinophilic gastroenteritis, and celiac disease 51 IBS occurs infrequently before late adolescence and may be preceded by a long history of constipation or an episode of gastroenteritis. The diagnosis of IBS can be made on the basis of symptoms; it need not be a diagnosis of exclusion . source:Thabane M,et al, 2010 52 Children who have IBS have a lowered rectal pain threshold and disturbed rectal contractile response to meals . Compared to control subjects and children with functional dyspepsia, children with IBS have abnormal pain referral after rectal distension. Adolescents who have IBS-type symptoms have higher anxiety and depression scores than do those without such symptoms . source:Halac U,et al 2010 53 The symptoms in some children do not meet the diagnostic criteria for IBS or functional dyspepsia, nor are they consistent with organic illness. This category most closely resembles, but is not a substitute for, the classically defined recurrent abdominal pain of childhood . Functional abdominal pain may be associated with visceral hyperalgesia, reduced threshold for pain, abnormal pain referral after rectal distension, or impaired gastric relaxation response to meals. 54 Abdominal migraine is characterized by recurrent episodes of abdominal pain, typically midline or poorly localized, dull and moderate to severe in intensity. Pain is associated with at least two additional features that may include anorexia, nausea, vomiting, and pallor. 55 Aerophagia is excessive air swallowing that causes ◦ progressive abdominal distension ◦ may interfere with dietary intake 56 The most important component of the treatment is reassurance and education of the child and family. The child and family need to be reassured that no evidence of a serious underlying disorder is present. The family and the child with functional pain might worry about the inability to identify an organic cause and may be resistant to a diagnosis of nonorganic disease. 57 Explanation in simple language that although the pain is real, there is no underlying serious disorder usually alleviates the anxiety in the patient and family. Children of families that do not accept a functional cause of the symptoms are more likely to have persistent somatic complaints and school absences. 58 The parents should be instructed to avoid reinforcing the symptoms with secondary gain If children have missed school or have been removed from routine activities because of the pain, it is important that they return to regular activities 59 Treatment goals should be set for return to function and minimizing pain. Cognitive-behavioral therapy is helpful in the short term for managing pain and functional disability Biofeedback, guided imagery, and relaxation techniques have been useful in some children with functional pain. Time-limited use of medications is usually part of the multidisciplinary approach. 60 The commonly used medications include acid suppressants for dyspepsia symptoms, antispasmodics, and low-dose amitriptyline. For chronic abdominal pain with IBS symptoms, antidiarrheals and nonstimulating laxatives are used. Peppermint oil for 2 wk improves IBS symptoms in children. There is no evidence that lactose-restricted diet and fiber supplements decrease the frequency of attacks in chronic abdominal pain in children. Proton pump inhibitors or visceral muscle relaxants (anticholinergics) have been used empirically but are often unhelpful in the absence of specific indication. 61 DEFINITION OF THERAPY DISORDER Cognitive behavioral Recurrent abdominal (family) therapy pain Recurrent abdominal Famotidine pain and dyspeptic symptoms Recurrent abdominal Added dietary fiber pain Recurrent abdominal Lactose-free diet pain Irritable bowel Peppermint oil syndrome Functional GI disorders, Amitriptyline Irritable bowel syndrome Irritable bowel Lactobacillus GG syndrome using Rome II criteria EFFECTIVENESS Beneficial Inconclusive Unlikely to be beneficial Unlikely to be beneficial Likely to be beneficial Inconsistent results Unlikely to be beneficial 62 Patients who have ulcer-like dyspepsia are treated for 4 to 6 weeks with H2-receptor antagonists. Patients who have dysmotility-like dyspepsia are treated for 4 to 6 weeks with prokinetic agents In fact, there are no objective data to support such a treatment. 63 There are no prospective studies of the outcome of any of the various presentations of functional abdominal pain. Reassuringly, retrospective studies suggest that organic disease rarely is masked in the context of a functional disorder. Once functional abdominal pain is diagnosed, subsequent follow-up rarely identifies an occult organic disorder. 64 After 5 years, approximately one third of children with RAP will have resolution of their pain, one third will continue to complain of the same symptoms, and another one third will have a different recurrent pain complaint. 65 Chronic abdominal pain is defined by pain of at least three months' duration, although some clinicians consider pain of more than one to two months' duration to be chronic. Recurrent abdominal pain is defined by more than three episodes of pain that are sufficiently severe to affect activity and that occur over the course of at least three months. 66 Referred pain usually is perceived to be near the surface of the body. It is located in the cutaneous dermatomes sharing the same spinal cord level as the visceral inputs. Referred pain may be correlated with skin hyperalgesia and increased muscle tone of the abdominal wall. 67