GASTROINTESTINAL DILEMMAS
| IRRITABLE BOWEL SYNDROME —Marvin Derezin, MD, Clinical Professor of Medicine, Division of Gastroenterology,
David Geffen School of Medicine at the University of California, Los Angeles
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| Introduction: irritable bowel syndrome (IBS) common; affects ≈20% of population; women more likely to seek
care than men; causes pain and discomfort; interferes with quality of life (QOL); not mental problem; reflex (eg,
reaction to stress); usually manifests during teenage years to age 40 yr (consider organic disease in patients >40
yr of age); causes loss of work and decreased concentration and productivity; when attributed to stress by health
care professional, patients may become demoralized and stop seeking help; IBS can be treated successfully
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| Work-up and patient history: perform organic work-up for patients >30 yr of age who present with new-onset
IBS symptoms; symptoms must be present for ≥3 mo; positive history of sexual abuse in 10% to 15% of
women with IBS; increased incidence in family members; IBS cannot be diagnosed if warning signs of organic
disease present; take understanding, compas-sionate, and reassuring approach; easy to diagnose IBS;
therapeutic trial without major work-up acceptable; warning signs of organic disease—awakening in middle of
night due to symptoms; weight loss; bloody stools; complete work-up required
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| Alternating diarrhea and constipation: categorized as IBS mixed (IBS M); patients may have cramping and abdominal
pain in morning with normal stools followed by diarrhea, then no bowel movements for 3 to 4 days;
discomfort; bloating; incomplete evacuation; straining with constipation or diarrhea; may be exacerbated by
stress and diet (eg, spicy or fatty foods, heavy meals); treatment—avoid stimulation of gut (eg, spicy foods);
bran and psyllium (eg, Metamucil) may worsen symptoms; antispasmodic drugs (eg, hyoscyamine [eg,
Levsin, Levbid; sublingual form available]) helpful; dicyclomine (eg, Bentyl), atropine, scopolamine, hyoscyamine,
or sulfate combination (eg, Donnatal), and chlordiazepoxide and clidinium (Librax) used less commonly
due to sedative properties (may be helpful to patients with anxiety); 2-wk therapeutic trial of low doses
(eg, 10 mg) of tricyclic antidepressants (TCAs; eg, amitriptyline, desipramine) at bedtime may be effective
(discuss side effects [eg, dry mouth]); behavioral therapy—identify stimulus for symptoms; hypnosis effective;
acupuncture, acupressure, and cleansing enemas not recommended
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| Constipation: long-term constipation may not require work-up for organic disease; advise patients >50 yr of
age about colonoscopy; consider polypharmacy (some medications can cause constipation) and patient’s misconceptions
about bowel movements (daily bowel movements not required); constipation may be due to sluggish
colon or obstructed defecation (due to, eg, improper movement of pelvic musculature); treatment—
exercise and large fluid intake ineffective; short trial of bulk agents acceptable (few patients respond to bulk
agents); bran can cause gas and cramping; laxatives—2 magnesia tablets (eg, Milk of Magnesia) at night (increase
up to 6 tablets as indicated); sennosides (eg, Senokot; increase dose slowly as indicated); bisacodyl (eg,
Dulcolax; no long-standing negative effects); polyethylene glycol solution (MiraLax) mixed with water at
night; tegaserod (Zelnorm) removed from market; lubiprostone (Amitiza; 24 mg bid with food; results expected
in 1-2 days; side effects include nausea)
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| Abdominal bloating: patients do not have more gas than normal; worsens as day progresses; sensitivity to
clothes on abdomen; bacterial overgrowth suggested as cause, but not certain (some patients respond to antibiotics);
treatment—check medications; avoid gas-forming foods; alpha-D-galactosidase enzyme (Beano);
data about probiotics promising; TCAs and selective serotonin reuptake inhibitors (SSRIs) for selected patients
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| Diarrhea: can occur with meals or stress; treatment—loperamide (eg, Imodium); diphenoxylate with atropine
(eg, Lomotil)
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| Summary: ask about recent stress; acceptance and compassion by physician important part of treatment; ≈1 in
100 people have celiac disease (screening cost-effective); probiotics (eg, Bifidobacteria) promising
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| GASTROESOPHAGEAL REFLUX DISEASE —Marcelo F. Vela, MD, Assistant Professor of Medicine, Division
of Gastroenterology and Hepatology, Medical University of South Carolina, Charleston
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| Introduction: daily heartburn experienced by 10% of adult population in United States (weekly heartburn by
≤15%); rate of relapse within 6 mo of stopping treatment, 80% (long-term therapy needed); yearly sales of
over-the-counter treatments >$1 billion (>$12 billion in prescription sales of proton pump inhibitors [PPIs]);
4 to 5 million office visits per year
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| Effects on QOL: QOL score for untreated reflux esophagitis lower than score for angina and mild heart failure;
treatment improves QOL
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| Occurrence of reflux: gastroduodenal factors—stomach normally produces acid and pepsin (injurious to esophagus;
amount related to gastric emptying); duodenal gastric reflux of bile into esophagus (injurious to esopha-
gus); gastroesophageal junction factors—barrier mechanism that blocks reflux comprised of lower esophageal
sphincter and crural diaphragm; protective mecha-nisms—peristalsis; mucosal defensive repair mechanisms
(eg, growth factors); bicarbonate in saliva that helps neutralize acid; gastroesophageal reflux disease (GERD)
results when barrier breached and defense mechanisms overwhelmed
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| Diagnosis of GERD: heartburn and regurgitation after meals may be relieved by antacids; determine whether
patient has alarm signs or symptoms (eg, dysphagia, odynophagia, bleeding, weight loss, anemia); if no alarm
signs present, proceed with therapeutic trial of PPI for 4 wk; if patient responds to therapy, no further work-up
(eg, endoscopy) needed; sensitivity of PPI trial (once-daily dose), 75% (specificity, 55%); endoscopy—used
to inspect esophageal mucosa (essential when alarm signs present); may show erosions; helps diagnose
esophagitis and identify Barrett’s esophagus; 66% of patients with reflux disease have normal endoscopy (ie,
nonerosive reflux disease [NERD]); pH testing—gold standard for diagnosing reflux disease; catheter with
pH electrode placed in distal esophagus; quantifies acid exposure over 24 hr; establishes associations between
episodes of acid reflux and symptoms; wireless pH moni-toring system available (advantages include greater
freedom for patients, eg, able to shower or exercise); barium swallow testing—not useful for diagnosis; sensitivity
and specificity for Barrett’s esophagus low; catches 80% of severe esophagitis, 25% of mild; may be
useful during preoperative evaluation (eg, provides information about hiatus hernia or esophageal shortening)
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| Lifestyle modifications: weight loss; new data show direct relationship between body mass index (BMI) and
acid reflux; greater acid exposure in esophagus with higher BMI; obesity independent risk factor for esophageal
adenocarcinoma; advise patients to avoid lying down for ≥3 hr after eating; elevate head of bed; decrease
fat intake; cease tobacco smoking; lifestyle modifications alone unlikely to resolve symptoms; little
data available about relaxation of lower esophageal sphincter with caffeine and alcohol
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| Medical treatment: suppresses acid; mechanism for acid production stimulated by histamine, gastrin, and acetylcholine;
H2 -blockers—rate of healing of erosive esophagitis ≈50%; PPIs—more potent than H2 -blockers;
rate of healing of erosive esophagitis 90%; rates of healing similar among omeprazole, pantoprazole, lansoprazole,
and rabeprazole; some data suggest using esomeprazole for severe erosive esophagitis may be advantageous
(no data about comparison to omeprazole and sodium bicarbonate [Zegerid]); some patients do
better on one PPI than another; length of treatment—long term; may attempt step-down (eg, if patient on
twice-daily PPI, consider reducing to once-daily or switch to H2 -blocker)
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| Side effects of therapy: medications well tolerated and safe; European data about omeprazole show low rate
(1%-3%) of minor side effects (eg, diarrhea, cramping, headache, nausea); initial concern about gastric carcinoids
or other forms of cancer “hasn’t panned out in humans”; Clostridium difficile—new retrospective data
based on large studies suggest long-term acid suppression with PPIs associated with higher rate of community-acquired
C difficile colitis (mild and treatable with antibiotics); less acid in stomach may promote C difficile
colonization; community-acquired pneumonia—2 or 3 studies show higher risk; studies problematic because
uncertain whether patients acquire pneumonia due to lowered acid levels, or whether reflux conveys risk for
pneumonia with aspiration; osteoporosis—long-term acid suppression may interfere with calcium absorption;
study saw higher rate of hip fracture in patients >50 yr of age who were on PPIs; speaker recommends calcium
supplementation with calcium citrate for patients at risk for osteoporosis
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| Refractory reflux: 30% of patients continue to complain of symptoms despite use of PPIs; refer for further evaluation;
causes of ongoing symptoms—1) ongoing acid reflux; insufficient acid suppression by PPIs; 2) ongoing
nonacid reflux; PPIs effective at suppressing stomach acid, but movement of gastric contents from stomach to
esophagus persists; different treatment approach required; 3) no reflux; look for other causes of symptoms,
eg, eosinophilic esophagitis or “functional heartburn” (akin to IBS; symptoms without organic cause)
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| Surgery: builds mechanical barrier to reflux; surgeons perform full (classic Nissen fundoplication) or partial
(Toupet fundoplication) wrap; ideal candidates—patients who respond to PPIs (patients who do not do well on
PPIs should not undergo surgery without testing [symptoms may not be caused by reflux, and may not improve
with surgery]); document reflux on pH study; surgery may be effective for nonacid reflux (promising
data emerging; impedance and pH studies must be documented); surgery vs PPI therapy—after 5 yr, loss of efficacy
of PPI therapy (≈80% of patients still doing well); slight numeric advantage for surgery, but no statistically
significant difference; surgery and PPI considered similarly effective in treating reflux; complications—
infec-tion of wounds; complications associated with anesthesia; late complications, eg, dysphagia during first 2
mo (in 5% of patients, chronic or debilitating dysphagia requires second surgery to undo wrap); diarrhea due to
alterations in stomach anatomy (smaller gastric capacity with more rapid emptying); gas and bloating due to inability
to belch or expel air; discuss option of PPI therapy
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| Endoscopic therapy: potential advantages—cost-effective; no surgical morbidity; outpatient procedure; no need
for long-term compliance; placement of endoscopic suturing devices builds barrier; radiofrequency energy
with balloon forms barrier in muscle and alters compliance to decrease reflux; full-thickness plication close to
surgical fundoplication promising; procedures in development
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| Summary: lifestyle modifications recommended for all patients; PPIs more effective than H2 -blockers (50% of
patients may respond to H2 -blocker); efficacy of different PPIs similar, except in cases of severe erosive
esophagitis, in which esomeprazole may be advantageous; long-term treatment required in most patients to
prevent recurrence; consider safety concerns of acid suppression (eg, osteoporosis, C difficile); try to step
down PPI therapy when patients become stable; refer patients with refractory reflux for further evaluation;
carefully select patients for surgery and discuss possible complications; endoscopic therapies may be useful
in future
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| Questions and answers: do you check vitamin B12 levels for patients on lifelong PPI therapy?—vitamin B12 levels not
routinely checked unless patient presents with megaloblastic anemia
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Suggested Reading
Al Sughayir MA: Hypnotherapy for irritable bowel syndrome in Saudi Arabian patients. East Mediterr Health J
13:301, 2007; Bellini M et al: The general practitioner's management of patients with a new diagnosis of irritable
bowel syndrome. J Clin Gastroenterol 40:87, 2006; Cayley WE Jr: Irritable bowel syndrome. BMJ 330:632,
2005; Croghan A et al: Recognizing and managing patients with irritable bowel syndrome. J Am Acad Nurse
Pract 17:51, 2005; El Sherif AM et al: Endoscopic antireflux repairs. Minerva Gastroenterol Dietol 53:189, 2007;
Hasler WL: Irritable bowel syndrome and bloating. Best Pract Res Clin Gastroenterol 21:689, 2007; Lacy BE et
al: Physicians' attitudes and practices in the evaluation and treatment of irritable bowel syndrome. Scand J Gastroenterol
41:892, 2006; Long JD et al: Nonerosive reflux disease. Minerva Gastroenterol Dietol 53:127, 2007;
Lowe DO et al: Proton pump inhibitors and hospitalization for Clostridium difficile-associated disease: a population-based
study. Clin Infect Dis 43:1272, 2006; O'Connell MB et al: Effects of proton pump inhibitors on calcium
carbonate absorption in women: a randomized crossover trial. Am J Med 118:778, 2005; Reymunde A et
al: Long-term results of radiofrequency energy delivery for the treatment of GERD: sustained improvements in
symptoms, QOL, and drug use at 4-year follow-up. Gastrointest Endosc 65:361, 2007; Triadafilopoulos G: Endotherapy
and surgery for GERD. J Clin Gastroenterol 41:S87, 2007; Whitehead WE et al: The usual medical
care for irritable bowel syndrome. Aliment Pharmacol Ther 20:1305, 2004.
Educational Objectives
| The goal of this program is to improve the management of irritable bowel syndrome (IBS) and gastroesophageal reflux
disease (GERD). After hearing and assimilating this program, the participant will be better able to:
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 | 1. Distinguish IBS from organic disease, based on signs and symptoms.
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| 2. Choose effective therapy for specific types of IBS, such as IBS with constipation or IBS with alternating diarrhea
and constipation.
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| 3. Prescribe an effective therapeutic regimen for GERD.
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| 4. Review side effects and risks of proton pump inhibitors.
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| 5. Identify candidates for surgery for the treatment of GERD.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose
relevant financial relationships within the past 12 months that might create any personal conflicts of interest.
Any identified conflicts were resolved to ensure that this educational activity promotes quality in health
care and not a proprietary business or commercial interest. For this program, the following has been disclosed:
Dr. Vela is on the Speakers’ Bureau and has received research support from AstraZeneca.
Acknowledgements
Dr. Derezin spoke in Los Angeles, CA, at the 34th Annual UCLA Family Practice Refresher Course, presented May
29 to June 2, 2007, by the David Geffen School of Medicine at the University of California, Los Angeles. Dr.
Vela was recorded in Kiawah Island, SC, at Intensive Review of Family Medicine, presented June 18-23, 2007, by
the Medical University of South Carolina. The Audio-Digest Foundation thanks the speakers and the sponsors
for their cooperation in the production of this program.
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