Abdominal Complaints in School Age Children Michael A. D’Amico, MD Pediatric Gastroenterology and Nutrition May 16, 2012 Objectives • Become familiar with common causes of abdominal complaints in school age children • Understand the therapeutic approach to these conditions • Know when to make appropriate referrals • Explore presentation content further with Q & A’s Statements • No financial disclosures • I may be discussing off-label use of some medications Common Abdominal Complaints • Developmental level of child – introspection • Comfort level • Social context Often difficult to express or verbalize precise sensation Common Complaints (symptoms) • Pain – Most common – Vague • Don’t feel well, My tummy hurts, Hunger, Nausea • Upset stomach • Constipation – Hard to go, takes a long time going • Diarrhea Common Complaints • Vomiting • Dysphagia – Difficulty swallowing • “Accidents” – Stool incontinence – Encopresis • Blood in stool – hematochezia Classification of Abdominal Pain • Organic • Non-organic – Aka: “Functional” abdominal pain – Avoid terms like psychogenic, nervous stomach or “its all in your head” Organic Causes of Chronic Abdominal Pain • Gastrointestinal – – – – – – – – – – – – – • Esophagitis Gastritis/Peptic Ulcer Malrotation/adhesions Duplications Hernias IBD Constipation Parasitic infection/infestation Bezoar or foreign body Carbohydrate intolerance Intussusception Tumor Ischemic • – • • Chronic hepatitis Cholelithiaisis/Cholecystitis Choledochal cyst Chronic pancreatitis/pseudocyst UPJ obstruction/hydronephrosis Nephrolithiasis Recurrent pyelo/cystitis Hematocolpos Mittleshmerz Endometriosis Metabolic/Hematologic – – – – – – • Infection, inflammation or tumor near diaphram Genitourinary – – – – – – Hepatobiliary/pancreatic – – – – Respiratory Porphria Hereditary angioedema DM Lead poisoning Sickle cell disease Collagen vascular disease Musculoskeletal – Trauma, tumor, infection Suggestive of Organic Cause of Chronic Abdominal Pain • • • • • • • • • • < 5 yrs Constitutional Sx: fever, wt loss, rash, joint pain Emesis (bilious, hematemesis) Pain that awakens from sleep Pain well localized away from umbilicus Referred pain Family Hx of IDB, PUD, etc Perianal disease Occult or gross blood in stool Abnormal testing Constipation • Likely the most common cause of complaints of abdominal pain in school age children • Will spend the most time on this today Constipation • Chronic constipation is a very common pediatric problem • Accounts for 3 – 5% of visits to primary provider • Up to 25% of referrals to pediatric GI • Male to female ratio is 6:1 • Parental anxiety/stress Constipation in children with disabilities • More common – 75 – 90% with neuromuscular and developmental disabilities • • • • Delay in diagnosis and treatment Longer therapy More medications and interventions More tests (x-ray, barium enema, manometry, colonscopy) Constipation: Definition • Passage of fewer than 3 stools per week or • Passage of painful, large hard stools regardless of frequency – Children may have fecal impaction with frequent small bowel movements “around” the impacted mass -- OVERFLOW • Subjective “Normal” stooling patterns • Frequency varies with age – Highly variable in early infancy depending on feeding source (breast-fed vs. formula) – By 4 months most infants average 2 stools/day (range 1 – 7/day in 93%) – Toddlers and school-age children average 1.2 bowel movements/day • Adults range from 3/day to 3/week Defecation • Fecal filling of the rectum • Reflex relaxation of the tonically contracted internal anal sphincter • Voluntary contraction of external anal sphincter • “Fecal continence” Defecation • Voluntary relaxation of external anal sphincter and puborectalis muscle “opens” and “straightens” passage • Straining (Valsalva maneuver), increasing intra-abdominal pressure and rectal contractions helps propel stool outside body • Coordinated by sensory epithelium of anorectal mucosa The Colon • Stores and desiccates liquid stool received from the ileum • Propulsive contractions stimulated by – Eating (gastro-colic reflex) – Distension (bulk) • Transit time increases with age and varies with nutritional (dietary) components of stool – mostly FIBER Constipation can be caused by • • • • • • Insufficient fiber intake Insufficient water intake Tumors, fractures or lesions Spinal cord/disc disease Large bowel nervous disorders Neuromuscular disorders/motility disorder – Paradoxical puborectalis contraction • • • • Metabolic or endocrine disorders Dehydration Medications Behavioral problems → usually multifactorial Withholding • Most common cause of constipation in children is withholding of stool – Usually because of a prior painful bowel movement (?associated anal fissure) • Subconscious • Initiates habit cycle of stool retention – Stretches rectum and later proximal colon – Reabsorption of fluid and electrolytes Withholding • Self-perpetuating – Larger and harder stools are more difficult to pass – Reinforcement of painful experience and further withholding • Leads to fecal impaction – Further stretching and so on and so on and…… → overflow incontinence (ENCOPRESIS) Pediatr Clin North Am 1982;29:315-30 Who’s affected? Encopresis • “Soiling” • Less common • Most commonly due to constipation – “Retention encopresis” – “Overflow incontinence” • Reported frequency varies – 1 – 8% of school-age children Encopresis • Involuntary leakage of liquid or semiformed stool around the constipated fecal mass is the usual trigger to bring patients to medical attention • Chronic rectal distension from fecal retention decreases sensation of stool volume which formerly caused the “urge” to defecate Medications • • • • • • • • Narcotic or opioid pain medications Anesthetics Anticholinergics/anti-spasmodics Anticonvulsants/ketogenic diets Antipsychotics/antidepressants/stimulants Barium Minerals: calcium, iron, lead, aluminum, bismuth Nonsteroidal anti-inflammatory agents Clinical Signs and Symptoms • Frequency of BM’s with chronic constipation may NOT be a reliable indicator • Other signs & symptoms such as abdominal pain and distension develop • Clogging the toilet • Frequent soiling or leaking may be confused as diarrhea or over treatment with stool softeners • Cyclic appetite blunting with periods of poor weight gain, followed by remarkable response to therapy Clinical signs and symptoms • Efforts to withhold may may be misinterpreted as attempts to strain or defecate • Common withholding maneuvers – – – – Posturing Scissoring of the legs Dancing back & forth, from leg to leg Occasionally resembling seizures Clinical signs and symptoms • Urinary incontinence – ~30% diurnal enuresis – 35% nocturnal • Recurrent urinary tract infection (~10%) • Physical exam – Abdominal mass – Peri-anal fissures, hemorrhoids So what can we do? A few basic tenets • Soften the stool • Provide a secure, conducive environment to sit, sit, sit Goals for Stooling • Soft, but formed stool • Upright position with knees/hips bent to maximize Valsalva • Feet securely planted on firm surface • Appropriately sized seat Treatment Maintenance • Keep the colon “clean” • Osmotic agents – Lactulose – Docusate (Colace) – Miralax • Mineral oil – Softener and emollient (lubricates) Maintenance • Bulking agents – Fiber • Stimulants – Senna (Sennakot) – Bisacodyl (Dulcolax) – Lose effect with time (tachyphylaxis) • Motility agents – Metoclopramide (Reglan) – Serotoninergic agonists Other Therapies • Biofeedback – Electromyography – Manometry • • • • Reward systems Individual or family therapy Pyschotherapy Pyschopharmacotherapy Patience Time Support and encouragement Prognosis • Generally good – The colon can and will return to normal caliber and function • Muscular • Sensory • Directly correlates with – ability to adhere to regimen and toileting – Retraining and resolution of withholding GERD The Antireflux Barrier Pathogenic Factors in GERD Pharynx UES Mechanisms of Esophageal Complications • Impaired esophageal clearance • Defective tissue resistance • Noxious composition of refluxate Esophagus Crural diaphragm Pylorus Mechanisms of GER • Transient LES relaxation • Intra-abdominal pressure • Reduced esophageal capacitance • Gastric compliance • Delayed gastric emptying Angle of His LES Stomach Mechanisms of Airway Complications • Vagal reflexes • Impaired airway protection Presenting Symptoms and Signs of GERD • • • • • Recurrent vomiting Poor weight gain Irritability in infant Heartburn Esophagitis • • • • • Dysphagia or feeding refusal Apnea or ALTE Asthma Recurrent pneumonia Upper airway symptoms Differential Diagnosis of Vomiting in Infants and Children GI Obstruction • Pyloric stenosis • Malrotation • Intermittent intussusception Infections • Sepsis • Meningitis • Urinary tract infection Allergic • Dietary protein intolerance GI Disorders • Achalasia • Gastroparesis • Gastroenteritis Neurologic • Hydrocephalus • Subdural hematoma • Intracranial hemorrhage Metabolic/Endocrine • Galactosemia • Fructose intolerance • Urea cycle defects Renal • Obstructive uropathy • Renal insufficiency Toxic • Lead Cardiac • Congestive heart failure Adapted from Rudolph et al, J Pediatr Gastroenterol Nutr 2001;32:S1 Pharmacotherapy • • • • • Antacids Histamine-2 receptor antagonists Proton pump inhibitors Prokinetic agents Surface agents Goals of Pharmacotherapy • Control symptoms • Promote healing • Prevent complications • Improve health-related quality of life • Avoid adverse effects of treatment Principles of Antireflux Surgery Restore intraabdominal segment of esophagus Approximate diaphagmatic crurae Reduce hiatal hernia when present Wrap fundus around LES to reinforce antireflux barrier Peptic Disease • PUD – peptic ulcer disease – Very uncommon in children • H. pylori gastritis – Acid-loving bacteria – Uncommon in young children Dietary Intolerance • Carbohydrate Intolerance – Most common form is Lactose Intolerance – Deficiency (primary or secodary) in small bowel enzyme LACTASE • Food allergy – Many possibilities • Cow/soy protein, nuts, fish, shell fish, wheat Dietary Intolerance • • • • • • Celiac disease Aka – Celiac sprue, Gluten sensitivity Autoimmune disease Environmental trigger Complex genetics Treatment: GFD (gluten free diet) Inflammatory Bowel Disease • Crohn’s Disease – Possibly entire GI tract • Ulcerative colitis – Restricted to large intestine (colon) Parasitic Infections • Giardia – Most common – Usually associated with diarrhea, weight loss • Round worms (nematodes) – Ascaris – Enterobius vermicularis (pinworms) Others (rare) • • • • • • Hepatitis Choledocholithiasis (gallstones) Kidney stones Pancreatitis Eosinophilic esophagitis Foreign bodies – (ie. bezoar) Chronic Recurrent Abdominal Pain • Chronic • Recurrent • Abdominal • Pain – Aka – Functional abdominal pain - Functional GI Disorders - Functional Abdominal Pain • Chronic or recurrent if at least 1 episode of pain occurs each month of 3 consecutive months AND is severe enough to interfere with functioning • ~10 to 15% of school age kids • More recently – up to 20% of middle & high school students report pain daily or weekly Functional Abdominal Pain • What is it? →→ Dysfunctional • What is it NOT? – Psychogenic – Imaginary – Malingering Functional Abdominal Pain • Genuine pain • Cannot be explained on the basis of structural or biochemical abnormalities • Generally localizable – Commonly periumbilical – Can be diffuse Epigastric FAP • Associated with nausea, vomiting, bloating, belching, early satiety • Confused with GERD, gastritis • Commonly “Non-ulcer dyspepsia” Periumbilical FAP • • • • Usually no associated symptomatology No change in bowel patterns No patterns or discernible triggers to pain Most common Infraumbilical FAP • Associated with cramps, distension, bloating • Altered bowel movements – Constipation – Diarrhea • Irritable Bowel Syndrome (IBS) Clinical Characteristics of FAP • • • • > 5 yrs Paroxysms of abd pain Location: periumbilical (epigastric, infraumbilical) Pain characterization: vague, non-localizing or radiating • Poor temporal correlation with activity, meal, bowel pattern • Interferes with normal activity – Direct relationship with time missed in school/work • Normal PE, laboratory/other studies Cyclic Vomiting Syndrome • Not rare –estimated ~1.9% incidence in children – Less common in adults • Diagnosis – average 9.6 years • Onset of Sx 5.3 years – Delay in diagnosis • F:M 1.2:1 • Cycles 4 -12/year CVS CVS • Likely a heterogeneous group of disorders • Most commonly linked to migraines – ? share a common pathophysiologic process • Also linked to food allergy, mitochondrial, metabolic, and endocrine disorders CVS and migraines • Linked to both migraine headaches and abdominal migraines – Abdominal migraines similar with core symptom pain – Both with high incidence of headache • Discreteness of episodes – normal health in between • Progression of cyclic vomiting to migraine headaches • Strong family history (~80%) • Response to antimigraine therapy CVS • Triggers – stress, illness, caffeine/foods, menstruation (catamenial) • Autonomic imbalance – Severe tachycardia, hypertension, and/or orthostasis during episodes – Autonomic imbalance with enhanced sympathetic and diminished parasympathetic vagal modulation (71%) To J, et al. J Pediatr 1999 Sep;135(3):363-6 The Brain-Gut Axis Brain-Gut Connection: Corticotropin Releasing Factor • Paraventricular nucleus (hypothalamus) • Dorsal vagal complex – Endogenous brain CRF mediates psychological, physical, somatovisceral, and immunological stressinduced delayed gastric emptying in rats. • Postoperative gastric ileus is prevented by peripheral injection of CRF antagonists. • CVS is precipitated by stimulation of CRF release – resulting endocrine, autonomic, and visceral changes are indicative of central CRF activation. Tache Y. Dig Dis Sci 1999 Aug;44(8 Suppl):79S-86S. Emotional Motor System • Overlap of brain regions concerned with processing visceral afferent innervation (mainly colon) with central autonomic regulation of GI motility and secretion • Rostral portion of the anterior cingulate cortex (ACC) is the visceromotor cortex – Projects to hypothalamic nuclei, amygdala, periaqueductal grey and brainstem nuclei Summary of FGIDs What can be done? Pharmacotherapy • Anti-spasmodics – (anti-cholinergics, anti-histamines) – Dicyclomine (Levsin, Bentyl) – Hycosamine • Serotoninergics – Agonist: Tegaserod (Zelnorm) – Antagonist: Alosetron (Lotronex) Antidepressants Tricyclics – 3° - Amitriptyline, Imipramine – 2° - Nortriptyline, Desipramine Lower doses than anti-depressant use provide: • anxiolytic effects • anti-nociceptive properties and facilitate central pain tolerance • peripheral analgesic effects at the level of visceral mechanoreceptors and afferent nerve fibers Antidepressants • SSRIs – Equivocal beneficial effects – Many due to anti-anxiety effects • SNRIs – No randomized trials in FGIDs (adults or kids) – Many open label studies and anecdotal data to suggest promise with less side effects than TCAs Non-pharmacologic Therapy • Cognitive Behavioral Therapy • Interpersonal dynamic psychotherapy • Deep muscle relaxation • Stress reduction techniques • Biofeedback CBT more effective in IBS than TCA and antispasmodics (~80%) Drossman DA, et al. Gastroenterology 2003 Psychosocial • Psychosocial aspects can not be underscored enough • “Continued symptoms coupled with negative work-ups (lack of definitive tests or marker), lack of understanding of parents and patients, and incomplete or ambivalent explanations from providers can lead to constant worry, fear and anxiety, thus perpetuating symptoms and influencing healthcare-seeking behavior adversely”. Syed IM, et al. Gastroenterology and Hepatology, 2006 Factors Influencing Long-Term Prognosis Factor Better Prognosis Worse Prognosis Sex Female Male Age of Onset > 6 yrs < 6 yrs Family Normal “Painful” Duration of Sx < 6 months > 6 months Education level > High school completed Socioeconomic class Middle-upper Lower Surgery Frequent Infrequent < High school Summary of FGID • FGIDs are a spectrum of biopsychosocial disorders that lack a diagnostic marker • Involve altered GI function, with dysfunction of brain-gut axis regulation • Focus should be a return to normal function, not complete resolution of pain. Take Home Message • Abdominal complaints are common in school age children • Many may be a symptom of underlying organic or functional disease • Some may be attempts at distraction from school work or attendance • Early referral for evaluation is important in cases of associated symptoms or significant academic or social dysfunction