Click here to view next page of this article

 

Peptic Ulcer Disease 

The major advent in peptic ulcer disease in the past decade has been our understanding of Helicobacter pylori. Helicobacter pylori was discovered in 1982. There is now conclusive evidence that 95% of patients with duodenal ulcers and 80% of patients with gastric ulcers are infected with Helicobacter pylori. Although healing of ulcers had previously been attainable with H2 blockers, recurrence rates remained extremely high until successful treatment for Helicobacter pylori was achieved. Epidemiologic studies have revealed that H. pylori infection is widespread affecting over a billion people worldwide. However, only a small fraction of these people develop peptic disease peptic ulcer disease, ulcer, stomach ulcer. Most researchers therefore conclude that H. pylori is a necessary but not sufficient factor for the development of peptic disease and other factors must as well be involved in the pathogenesis of ulcers.

H. pylori is gram-negative spiral-shaped bacterium that colonizes human gastric mucosa and the infection may persist for life. The transmission of infection is person to person, and the infection is usually acquired in childhood. It is not known whether the oral-fecal or oral-oral route is most important in transmission. Risk factors for contracting H. pylori infection include 1) living in a developing country, 2) being of lower socioeconomic status, 3) being African-American or Hispanic, or 4) living in crowded domestic conditions.

Diagnosis Testing:

1) Histology: The gold standard for H. pylori detection is considered biopsy of the antrum using special stains (Warthin-Starry or crestyl violet). The drawback of this method is that endoscopy is required and it is therefore expensive. The test is effective in diagnosing the disorder and is useful in following up patients after treatment.

2) Antral Biopsy with Culture: Although this is 100% specific, the sensitivity rate is lower than on histology, and so this is rarely used as a diagnostic method.

3) Biopsy Urease Test: With this method antral biopsies are taken at the time of endoscopy and put in a urea slant. Because the organism has the ability to split urea, this is easily detected with a calorimetric free agent. This exam is less expensive than histology and its specificity is almost as good. However, it remains somewhat less sensitive. It, too, can be used in followup to look for eradication of the organism.

4) Serologic Testing: Serologic testing for H. pylori is attractive in that it is readily accessible, relatively inexpensive and noninvasive. Techniques to test for antibodies of IgG, IgA and IgM type have been developed. However, only antibodies of the IgG type have been found to correlate with the presence of active infection. Rapid office tests are available for H. pylori antibodies and are sensitive (95%) but appear to be less specific than laboratory based tests. Because of this, rapid office tests are generally used as a screening and if positive, confirmed with laboratory based tests. The serologic tests are good in looking for infection in patients who have been treated; however, since it takes approximately a year for antibody titers to fall, they are not useful in detecting.

Treatment for Helicobacter Pylori

The NIH Consensus Conference on H. pylori recommended treatment of H. pylori infection only in infected patients who had developed gastric or duodenal ulcers. Anti H. pylori treatment was not recommended in patients who are H. pylori positive if ulcer disease was not documented, even in patients with symptomatic dyspepsia. As treatment for these agents improve, these recommendations may change. A large number of antibiotic regimens are available to treat H. pylori infection. Most modern treatment regimens include a proton pump inhibitor such as lansoprazole or omeprazole used in high doses. Additionally, as clarithromycin has been shown in vitro to be the most effective agent, this generally is included in the regimens.

The oldest regimen and the best studied remains the original triple dog regimen (tetracycline 500 mg qid, metronidazole 250 mg PO tid, and bismuth subsalicylate 2 tabs qid for 14 days). This regimen was successful in eradicating infection in 90% of patients. However, it was poorly tolerated by the majority of patients. Later, two drug regimens such as omeprazole and clarithromycin were tried. However, Successful rates dropped to the 70-80% range: One of the more successful regimens being used now is metronidazole 500 mg PO, bid., Biaxin 250 mg PO bid, and omeprazole 20 mg PO bid, for 7-14 days. This regimen is extremely well tolerated by patients, requires only bid, dosing and is effective in eradicating H. pylori in greater than 90% of patients. It must be remembered after the course of H. pylori treatment to complete a six week course of either proton pump inhibitor or H2 blocker to heal the underlying ulcer. It is only felt critical to document H. pylori in patients who have had complications of their peptic disease such as GI bleeding.