Adult Gastrointestinal Problems



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.

Workup: FIRST determine that it is indeed diarrhea and not simply an occasional loose stool or frequent defecation of formed stools.
Treatment: The vast majority should be managed by maintaining hydration and waiting for the spontaneous resolution of symptoms.
Prophylaxis is the main treatment for traveler's diarrhea. Consider: doxycycline, trimethoprim-sulfa, Pepto-Bismol, or Lomotil. Best prophylactic step = extreme caution in what one eats or drinks while traveling. Workup: Thorough history with complete physical exam may suggest laboratory studies (CBC, differential, platelets, ESR, Astra, serum/urine amylase, liver function tests, serum calcium and glucose, eosinophil count, serum carotene and B12 levels, sigmoidoscopy, multiple stool exams for OCP, Wright's stain, occult blood, viral and bacterial stool cultures, stools for fat, barium enema, UGI.

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).

Peptic Ulcer Disease

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.


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-
H pylori-
Asymptomatic (no ulcer)
Nonulcer dyspepsia
Gastric ulcer
Duodenal ulcer

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
not Doxycycline


not Ampicillin

2 tablets 4 
times daily 
with meals and
at bedtime
500 mg 4 times
daily with 
meals and at 
250 mg 4 times
daily with 
meals and at 
500 mg 2 or 3
times daily
with meals
500 mg 4 times
daily with 
meals and at 
20 mg twice
daily before
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)

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


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

Referral and Admission:

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.

Gastroesophageal Reflux Disease

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

Primary Tests and Findings




Barium swallow
Excessive reflux of barium

Exclusion of complications of reflux, such as strictures, ulcers, Barrett's esophagus

Bernstein test (acid titration)
Symptoms reproduced with acid

24-hour esophageal monitoring
Detection and quantification of reflux


Irritable Bowel Syndrome ("irritable colon syndrome," "mucous colitis," spastic colon"):

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
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.

Indications for referral and admission:


American Society for Gastrointestinal Endoscopy

B. Pope, MD
updated 8/30/05
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