IBS/Lactose/Celiac - GI Flashcards
IRRITABLE BOWEL SYNDROME (IBS)
-Chronic abdominal pain
-Altered bowel habits in the absence of any organic cause
-Approximately 15 percent of those affected actually seek medical attention
-Most commonly diagnosed gastrointestinal condition
Primary Characteristic:
-Chronic abdominal pain
-Altered Bowel Habits
-Location of Pain Can Vary
-The severity of the pain may range from mildly annoying to debilitating
-Defecation often provides some relief
CAUSE OF IBS
UNKNOWN Theories: -Gastrointestinal Motility Problem -Visceral Hypersensitivity -Intestinal Inflammation -Lymphocytes—Increased -Mast cells -Proinflammatory cytokines -Post-infectious -Alteration in fecal microflora -Bacterial Overgrowth -Small intestinal bacterial overgrowth (SIBO) -Food Sensitivity -Carbohydrate malabsorption -Genetics -Psychosocial Dysfunction
Types of IBS
CONSTIPATION PREDOMINANT IBS
- (hard or lumpy stools ≥25 percent / loose or watery stools <5 percent of bowel movements)
Mixed IBS
-(hard or lumpy stools ≥25 percent / loose or watery stools ≥25 percent of bowel movements)
Abdominal pain in IBS can vary BUT SHOULD NOT be associated with:
- weight loss
- rectal bleeding
- anemia
- should NOT be nocturnal or progressive.
TREATMENT OF IBS
-Relief of symptoms
-Addressing the patient’s concerns
-Why is the patient seeking help at this time?
-Patient Education
-Dietary Modifications?
-Lactose?
-Gluten Intolerance? (not celiac)
-Fiber
-Physical Activity
-Psychosocial therapies
-Exclusion of Gas causing foods? =Fructans (found in wheat, onions, and artichokes), Galactans (found in legumes, cabbage, and Brussels’ sprouts), Lactose, Fructose, Sorbitol, Xylitol
Mannitol
Pharmacologic Treatment of IBS
- Adjunct Only
- Choice depends on type of IBS (diarrhea vs constipation predominant)
- For postprandial abdominal pain, gas, bloating, and fecal urgency : Antispasmodic agents(cimetropium, and pinaverium (Intestinal wall relaxation)), Anticholinergic agents (Dicyclomine (Bentyl)and hyoscyamine (Anaspaz, Levsin))
- Dicyclomine:20 mg orally four times daily as needed
- Hyoscyamine:0.125 to 0.25 mg orally or sublingually three to four times daily as needed
- Sustained release hyoscyamine0.375 to 0.75 mg orally every 12 hours
- Antidepressants: Tricyclics (avoid in IBS Constipation predominant), SSRIs and SNRIs not as clear evidence for benefit. , Antidepressants not effective in children with IBS
Diarrhea Predominant IBS
- 5-hydroxytryptamine (serotonin) 3 receptor antagonists
- Alosetron (Lotronex)selective 5-HT3 antagonist
- women with severe diarrhea-predominant (IBS)
- failure to respond to conventional treatment.
- adverse effects including severe constipation and ischemic colitis.
Alosetron
six months and curtail daily activities,
-Fraction of these have diarrhea-predominant symptoms.
-Proportion of IBS patients eligible for alosetron is small.
To prescribe alosetron provider must:
-Self-attest to their qualifications
-Agree to educate patients on the risks and benefits of treatment and provide patients a copy of the FDA-approved medication guide
-Obtain a written agreement from patients before their initial prescription
-Affix a sticker onto prescriptions indicating that they are enrolled in a program to use alosetron
-Starting dose 1 mg once daily; Increase to 1 mg twice daily after four weeks if the lower dose is well-tolerated but does not adequately control symptoms
Constipation Predominant IBS
- Lubiprostone— locally acting chloride channel activator that enhances chloride-rich intestinal fluid secretion.
- Approved by the FDA for treatment of irritable bowel syndrome with constipation in women 18 years and older.
- There have been no comparisons with other options for treatment of IBS with constipation.
- Long-term safety remains to be established.
LACTOSE INTOLERANCE
- Europe and the United States, prevalence is 7 to 20 percent in Caucasian adults
- 80 to 95 percent among Native Americans,
- 65 to 75 percent among Africans and African Americans
- 50 percent in Hispanics
- Exceeds 90 percent in some populations in eastern Asia.
LACTOSE DIGESTION
- Lactose digestion is the rate-limiting step in the overall process of its absorption.
- Lactose is hydrolyzed by intestinal lactase to glucose and galactose on the microvillus membrane of the intestinal adsorptive cells
- Uptake of these monosaccharides is accomplished by the sodium-dependent glucose carrier.
- Defects in this transporter result in severe diarrhea following carbohydrate intake
- Lactose not absorbed by the small bowel is passed rapidly into the colon.
- Up to 75 percent of lactose passes unabsorbed through the small intestine toward the cecum and colon in individuals with lactasedeficiency
- In the colon, lactose is converted to short-chain fatty acids and hydrogen gas by the bacterial flora.
Causes of Lactose Malabsorption
- Racial or Ethnic
- Developmental: Premature infants have low lactase levels. Colonic salvage can give them nutrients needed.
- Congenital lactase deficiency—Congenital lactasedeficiency (CLD) is a rare autosomal recessive disorder. Absence of Lactase in small intestine.
Clinical symptoms of lactose intolerance:
- Diarrhea
- Abdominal pain
- Flatulence after ingestion of milk or milk-containing products.
- Abdominal pain,
- Bloating,
- Flatulence,
- Diarrhea,
- Vomiting (particularly in adolescents)
- Pain may be crampy
- Often localized to the periumbilical area or lower quadrant.
- Borborygmi
- Stools bulky, frothy, and watery.
DIAGNOSIS
-Lactose Tolerance Test: Affected by diabetes, bacterial overgrowth, gastric emptying, Cumbersome
Lactose breath hydrogen test
- Measures lactose nonabsorption.
- simple to perform, noninvasive
- sensitivity and specificity that are superior to the absorption test
- Breath hydrogen value of 10 ppm (parts per million) normal.
- 10 and 20 ppm indeterminate unless accompanied by symptoms
- Values over 20 ppm diagnostic of lactose malabsorption
- Abnormal lactose breath hydrogen test in children less than five years reflects
- abnormal intestinal mucosa or bacterial overgrowth, both of which require further evaluation by appropriate diagnostic tests
TREATMENT
- Eliminating symptoms
- Helping patient adapt to a gradual increase in lactose intake.
- Reduced dietary lactose intake
- read labels of commercially prepared foods
- Ice cream and milk highest concentration of lactose
- Cheese lower in lactose
- May attempt reintroduction of small quantities after a time of abstinence. High fat, high sugar foods best to start with. (Ice cream!)
- Substitution of alternative nutrient sources to maintain energy and protein intake
- Administration of a commercially available enzyme substitute.
- Maintenance of calcium and vitamin Dintake
Celiac Disease (Small Bowel Enteropathy)
- Celiac disease is an immune disorder that is triggered by an environmental agent (gluten) in genetically predisposed individuals
- Gluten is found in Wheat, Barley, Rye. Controversy as to whether in oats.
- Primarily in Caucasians. In Europe and the United States, prevalence estimates range from 1:80 to 1:300 children (3 to 13 per 1000 children)
- Females are affected approximately twice as often as males, although the ratio varies depending on the strategy used to find cases
Small bowel disorder characterized by:
- mucosal inflammation
- villous atrophy
- crypt hyperplasia,
- occurs upon exposure to dietary gluten
- improves after withdrawal of gluten from the diet.
Skin Conditions Associated with Celiac
- Dermatitis herpetiformis
- Acquired ichthyosis
- Cutaneous amyloid
- Cutaneous vasculitis
- Eczema
- Epidermal necrolysis
- Nodular prurigo
- Pityriasis rubra pilara
- Pustular dermatitis
Classic Celiac Disease
- Symptoms of malabsorption such as steatorrhea, weight loss, or other signs of nutrient or vitamin deficiency
- Presence of characteristic histologic changes (including villous atrophy) on small intestinal biopsy.
- Resolution of the mucosal lesions and symptoms upon withdrawal of gluten-containing foods, usually within a few weeks to months.
Silent/subclinical celiac disease
- Extraintestinal manifestations are predominant, and there are few or no gastrointestinal symptoms.
- No discernible symptoms of celiac disease
- Positive specific serologic test for celiac disease
- Biopsy evidence of villous atrophy.
- Usually detected by screening of high-risk groups.
- “Silent” may be a misnomer; after treatment with a gluten-free diet, many of these patients retrospectively recognize symptoms that they had not previously considered to be abnormal.
Latent celiac disease
- Normal jejunal mucosa and no/or minor symptoms at least at one time point while on a normal, gluten-containing diet
- Two variants of latent celiac disease have been identified:
- Celiac disease was present before, usually in childhood; the patient recovered completely with a gluten-free diet, remaining quiescent even when a normal diet is adopted.
- A normal mucosa was diagnosed at an earlier occasion while ingesting a normal diet, but celiac disease developed later.
Serologic evaluation
IgA endomysial antibodies (IgA EMA)
- sensitivity 85 to 98 percent; specificity 97 to 100 percent
- moderately sensitive and highly specific for untreated celiac disease
- Good marker of disease treatment
IgA tissue transglutaminase antibodies(IgA tTG)
-sensitivity 90 to 98 percent; specificity 95 to 97 percent
IgA antigliadin antibodies*(IgA AGA –
-sensitivity 80 to 90 percent; specificity 85 to 95 percent
IgG antigliadin antibodies*(IgG AGA) –
- sensitivity 75 to 85 percent; specificity 75 to 90 percent
- Many false positives, not in favor anymore as initial testing.
Management
- Foods containing wheat, rye, and barley should be avoided.
- Soybean or tapioca flours, rice, corn, buckwheat, and potatoes are safe.
- Read labels on prepared foods and condiments carefully, paying particular attention to additives such as stabilizers or emulsifiers that may contain gluten
- Dairy products should be avoided initially since many patients with celiac disease have secondary lactose intolerance.
- Distilled alcoholic beverages, vinegars and wine, are gluten free.
- Beers, ales, lagers, and malt vinegars often made from gluten-containing grains and are not distilled.
