Adult Gastrointestinal Problems

• Learn to diagnose common adult gastrointestinal illnesses, with emphasis on peptic ulcer disease and gastroesophageal reflux disease.
• Learn appropriate indications for radiographic and endoscopic procedures in the work-up of dyspepsia.
• Understand the role of Helicobacter pylori in PUD, chronic gastritis, and gastric carcinomas.
• Learn appropriate empiric and definitive pharmocotherapy for common gastrointestinal illnesses, including treatment for H. pylori.

Complaints related to the digestive system are frequently encountered in an ambulatory clinic setting. The discomfort may be psychogenic or stress or diet related. Local or systemic diseases may manifest as gastrointestinal symptoms. Most problems tend to overlap, with both functional and organic causes. The introduction of modern diagnostic techniques and medicines has altered this field dramatically; however, basic understanding and appreciation of the presenting signs and symptoms remain the most important diagnostic tools available.

Diarrhea is defined as an increase in frequency, fluidity, and volume of bowel movements. Most episodes are brief, self-limiting, and well tolerated without need for medical attention (increased water content of stools = common denominator).

Exudative diarrhea is due to infection and inflammation. Secretory diarrhea is due to enterotoxins, bile acids, oversecretion of gastrointestinal hormones. Osmotic diarrhea is due to unabsorbed solutes in the intestine.

• Clinical presentation - depends on site of involvement:

• small bowel diarrhea - passage of large, loose stool in conjunction with periumbilical or RLQ pain.
• large bowel diarrhea - passage of frequent, small, loose stools in conjunction with crampy, LLQ pain.

• Differential diagnosis (Table 1).
• Acute or traveler's diarrhea:

• thorough history: recent travel? medications? contacts with recent diarrhea? recent food consumption? previous history of diarrhea?

• thorough physical exam:

R/O acute abdomen, appendicitis.

• laboratory studies:

• NO TEST may be indicated if the patient is afebrile and feels well except for frequent loose stools.

• routine blood studies: CBC with diff, platelets, ESR, Astra - abnormalities indicate more severe disease.

• stool:

(a) hemocult - positive = inflammation, infection, neoplasm
(b)stool leukocytes (Wright's stain): if present, inflammatory bowel disease and bacterial infections that invade the mucosa are likely causes; if absent, viral disease, parasites, or irritable bowel syndrome are the most likely causes.
(c) ova, cysts, parasites - must examine at least 3 fresh stool samples.
(d)Gram stain - staphylococcal and candidal overgrowth can be recognized.
(e) culture - bacterial and viral.

• Sigmoidoscopy: do without prepping the bowel with cleansing enemas; take stool samples, scrape and biopsy abnormal mucosa.

• CORRECT PHYSIOLOGIC CHANGES induced by diarrhea, i.e., acid-base, fluid, electrolytes.
• diet:

• clear liquids in frequent amounts (Gatorade, Pedialyte, "flat" 7-Up or Coke, broth) for 24-48 hours, temporarily withholding solid food.
• if no diarrhea after 24-48 hours, may advance to small, frequent feedings of "BRAT" diet (Bananas, unbuttered Rice, Applesauce, and dry Toast).

• antidiarrheal preparations - generally not indicated, as this is self-limited.
• anticholinergics - for acute diarrhea with anxiety (see Irritable Bowel Syndrome).
• antibiotics - should NOT routinely be used for acute bacterial diarrhea. Exceptions: Elderly or debilitated patients who would be endangered by sepsis, or patients with dysentery caused by shigellosis, campylobacter, yersenia, or pseudomembra-nous colitis, where specific antibiotic treatment is indicated, or in symptomatic parasitic infections, where Flagyl is indicated.

• Chronic diarrhea:

Treatment: To be effective, therapy must be etiologic. Simply suppressing symptoms without identifying a cause may delay identification of a serious underlying condition (i.e., colon cancer).

• Indications for admission or referral (most patients can be managed out-patient):

• Inability to maintain oral hydration with subsequent IVVD (requiring parenteral fluid replacement).
• Infants, elderly persons, and those with chronic/debilitating illness are particularly vulnerable to complications of IVVD.
• Inflammatory diarrhea (bloody, purulent diarrhea and fever).
• Referral is indicated for patients with complicated inflammatory bowel disease, undiagnosed chronic diarrhea, or requirement of colonscopy or intestinal biopsy, or patients strongly suspected of having parasitic disease who repeatedly have negative stool samples for OCP and who require small bowel sampling.

Most peptic ulcers arise in the stomach (lesser curvature) and duodenum (bulb), areas exposed to gastric acid and pepsin. The mechanism of ulcer formation is incompletely understood, but appears to involve the interplay of aggressive and defensive factors in the gastroduodenal mucosa. Part of that imbalance is related to infection with Helicobacter pylori, although the mechanism whereby the infection results in peptic ulcer disease is not well understood.

H. pylori causes over 95% of peptic ulcers. It also causes histologic gastritis and most cases of gastritis not associated with a known primary cause (e.g., eosinophilic gastritis), and is being implicated as a cause of gastric carcinoma.

Presentation: Gastric and duodenal peptic ulcers are somewhat similar but rather non-specific. Patients may present with pain, bleeding, or obstruction, or they may be symptom-free.

• Peptic disease: Epigastric pain relieved by antacids, occurring in clusters of daily symptoms for a few weeks, separated by pain-free periods of months.

• Duodenal ulcer pain: Classically relieved by food, absent before breakfast, and responsible for awakening patient at night; it starts 2-3 hours after a meal.

• Gastric ulcer pain: More likely precipitated by food and often radiates from the epigastrium to the back or substernal region.

• Presumptive diagnosis: often made on clinical grounds alone.
• Diagnostic procedures: endoscopy or upper GI series, CBC, stool for occult blood.

  Endoscopy is indicated in patients with refractory symptoms or alarm symptoms. These include:

  • age < 60
  • severe nausea or vomiting
  • weight loss
  • early satiety
  • evidence of GI bleeding
  • dysphagia or odynophygia

H. pylori infection is currently diagnosed by either endoscopic biopsy or serologic titers for a specific immunoglobulin (IgG) antibody. No noninvasive technique to document eradication of infection is presently available, although urea breath tests will soon simplify both diagnosis of infection and documentation of eradication.

Therapy: The major objectives are to speed healing, reduce pain, and prevent complications and recurrences while minimizing the costs and side-effects of therapy.

A 1994 NIH Consensus Development Conference panel recommends that all patients with duodenal or peptic ulcers receive antimicrobial therapy if H. pylori is present (Table 2). Eradication of H. pylori results in faster healing of ulcers, with a markedly decreased rate of ulcer recurrence.
 

Table 2. When to Begin Antimicrobial Treatment of Helicobacter pylori Infection: * Guidelines
Diagnosis	H pylori- negative	H pylori- positive
Asymptomatic (no ulcer) Nonulcer dyspepsia Gastric ulcer Duodenal ulcer	No No No No	No No Yes Yes

Documentation of an ulcer and H. pylori should occur before treatment for H. pylori is considered. Eradication should be attempted in patients with chronic PUD severe enough to prompt consideration of long-term maintenance therapy or elective surgery, and in patients already receiving maintenance therapy.

Tables 3 and 4 list recommended regimes for treating H. pylori. If active disease is present at diagnosis of H. pylori, antisecretory therapy should be administered concurrently.
 
 

Table 3. Antibiotic Doses
Bismuth  Subsalicylate	Tetracycline not Doxycycline	Metronidazole	Clarithromycin	Amoxicillin not Ampicillin	Omeprazole
2 tablets 4  times daily  with meals and at bedtime	500 mg 4 times daily with  meals and at  bedtime	250 mg 4 times daily with  meals and at  bedtime	500 mg 2 or 3 times daily with meals	500 mg 4 times daily with  meals and at  bedtime	20 mg twice daily before meals

Drug Combinations and Helicobacter pylori Cure Rates
Drug Combination (duration)	95% Cls
BMT (1 wk) BMT (2 wks) BMT and Omeprazole (1 wk) BMT (1 wk) BMT (2 wks)	86-90 88-90 94-98 75-81 80-86

 
 

Table 4. Antibiotic Doses
Omeprazole	Metronidazole	Chlarithromycin	Amoxcillin not ampicillin
20 mg twice daily defore meals and loading dose	500 mg twice daily with meals	500 mg twice daily with  meals	1 g twice daily with meals

Drug Combination and Helicobacter pylori Cure Rates
Drug Combination (duration)	95% Cls
MOC (1 wk) AOC (1 wk) MOA (1-2 wks)	87-91 86-91 77-83

 

Maintenance therapy with antisecretory agents should still be used in patients with bleeding ulcers.

• Duodenal ulcer:

• Choice of agent: physician and patient preference. Antacids, histamine H2-receptor antagonists (cimetidine [Tagamet] and ranitidine [Zantac]), sucralfate (Carafate), and proton pump inhibitors (omeprazole [Prilosec]) all speed the healing of duodenal ulcers.

• Duration of therapy: at least 4 weeks; may require maintenance therapy if recurrence in one year, especially if patient continues to smoke.

• Gastric ulcer:

• Choice of agent: Antacids, H2-receptor antagonists (Tagamet or Zantac), omeprazole (Prilosec), or sucralfate (Carafate) all speed the rate of healing.

• Duration of therapy: Healing usually requires longer course of therapy Ñ up to 12 weeks. Maintenance therapy helps to prevent recurrence, however, total suppression of acid production is unnecessary.

• Non-pharmacologic therapy:

• Diet - (+/-) - except coffee and alcohol, which must be excluded.
• Avoidance of agents injurious to the mucosal barrier, e.g., unbuffered aspirin.
• Alleviation of emotional stress.
• Stop smoking.

• Pharmacologic agents:

• Antacids - mainstay of therapy: 30-60 ml po one hour pc and hs.
• Histamine H2-receptor antagonists:

• Cimetidine (Tagamet): 300 mg po qid or 800 mg po hs.
• Ronitidine (Zantac): 150 mg po bid or 300 mg po hs.

• Sucralfate (Carafate): 1 gram po one hour ac and hs with large glass water (forms a barrier on ulcer base, inhibiting pepsin activity and binding bile salts).

• Anticholinergic agents: suppress the parasympathetic muscarinic activity that triggers gastric acid secretion, especially the nocturnal stage.

• Prostaglandin analogues: currently undergoing clinical testing. Misoprostol (Cytotec), a synthetic prostaglandin E analogue, may be used in patients taking NSAIDs (arthritis, etc.)

Refractiveness to therapy is indication for referral. Elective surgery: difficult issue, multiple variables. Consider surgery if major bleeds, gastric outlet obstruction, evidence of malignancy, intractable pain.
 
 

Presentation: Typically associated with substernal burning (heartburn) occurring most often after meals. Aggravated by lying down, bending over, lifting objects (10% have only chest pain). May mimic angina-- initiated by exercise, radiating to the arms and jaw. Relative occurrence: Common and treatable. Always consider coexistence of coronary artery disease with gastroesophageal reflux disease.

Primary Tests and Findings

Test: Barium swallow
Finding: Excessive reflux of barium

Test: Endoscopy
Finding: Exclusion of complications of reflux, such as strictures, ulcers, Barrett's esophagus.

Test: Bernstein test (acid titration)
Finding: Symptoms reproduced with acid

Test: 24-hour esophageal monitoring
Finding: Detection and quantification of reflux
 

Treatment:

• Non-Medical Therapy: Bed blocks (4-6 inch blocks under head of bed), diet (no food before sleep; no coffee, chocolate, alcohol), cigarette smoking avoided.

• Medical Therapy:

• Antacids (for mild and intermittent symptoms)
• H2 receptor blockers (up to 12 weeks may be needed)
• Proton pump inhibitor (omeprazole)(for severe or refractory reflux)
• Metoclopramide (Reglan) in patients refractory to H2 receptor blockers
• Avoid anticholinergics (they increase lower esophageal sphincter pressure)

Definition: Functional disturbance of intestinal motility, strongly influenced by emotional factors.

Presentation: Common presentation is diarrhea alternating with constipation, reflecting the different responses to stress, with bloating, nausea, headaches. Pain typically is achy rather than crampy, often LLQ, often relieved by bowel movement. A distinguishing characteristic of patients who suffer from IBS is their exaggerated emotional response to their bowel symptoms. (female to male ratio is 3:1)
 

Agent	Oral Therapy	Parenteral Therapy
Cimetidine Ranitidine	300 mg qid 150 mg bid	300 mg q 6 hr 50 mg q 8 hr

Work-up: History very suggestive, physical exam usually completely normal. Laboratory (depends on information suggested by history and physical, and chronicity of complaints): SMA, CBC, UGI, BE, sigmoidoscopy, sed rate, stool for occult blood, mucus, OCP - usually normal.

Clinical course: Chronic, relapsing condition; severity of symptoms waxes and wanes, depending on stress factors; no evidence of significant morbidity or mortality.

Management: Patient education, support, diet, and as a last resort, drugs for symptomatic relief.

• The first rule is to take the patient's symptoms seriously and not dismiss them as inconsequential or imaginary. Address patient's underlying concerns (cancer, inflammatory bowel disease). Most important: provide a specific diagnosis, because most patients with IBS will not accept a conclusion that "there is nothing wrong with your bowels."

• Identify and address patient's psychological difficulties-- often anxiety disorders, depression, and/or hysteria:

• Anxiety: Doxepin (antidepressant with anxiolytic properties); must avoid benzediazepines (diazepam), as these agents will worsen depression.
• Depression: Tricyclic antidepressants (amitriptyline 25 to 50 mg po hs).
• Hysteria: Usually best to stop medication and increase supportive therapy.

• Dietary manipulation: Sometimes helpful, but usually unnecessary unless there is a strongly suggestive history of intolerance to a food or substance:

• Bran and high fiber diets (with increased exercise) when constipation is predominant symptom.
• Bulk agents (Metamucil) often helpful with symptoms of diarrhea or constipation.
• Restrict offending foods or substances: "food allergies," "food intolerance," "lactose intolerance," "glutin intolerance," citrus fruits, caffeine, alcohol.

• Drug therapy: Stop all non-essential medicines that may affect bowel function, especially irritant laxatives, at onset of therapy:

• Disabling diarrhea may benefit from short course of Lomotil.

• Severe abdominal pain and distention may benefit from short course of anticholinergic agent (Bentyl 20 mg po qid).

• Avoid sedatives and combinations of preparations of tranquilizers and anticholinergics.

• Lotronex may be helpful in females with IBS with diarrhea as the predominant symptom.

Contraindicated for IBS with constipation symptoms.

• Referral is helpful when there are refractory disabling symptoms, such as uncontrollable diarrhea, or when serious psychopathology is encountered.

• Admission may, in rare circumstances, be appropriate and very beneficial in helping the patient learn new means of coping with stress and providing a respite from an intolerable living situation.

American Society for Gastrointestinal Endoscopy

---

B. Pope, MD
updated 8/30/05

---