Correlation between basal acid output and daily ranitidine dose required for therapy in Barrett's esophagus

Time series analysis of gastric acid secretion over a 20-year period in normal Japanese men

BACKGROUND

The gastric acid secretion level is an important determinant for the manifestation of the gastroesophageal reflux disease spectrum, finally leading to the development of esophageal adenocarcinoma (EAC). Although the incidence of EAC has remained low in Asia, understanding the recent trend in gastric acid secretion should be helpful in estimating future incidences of EAC in that area. We investigated the latest chronological change (1995-2014) in gastric acid secretion in normal Japanese patients.

METHODS

A total of 307 asymptomatic Japanese men who attended the clinic for annual endoscopic checkups from 1995 to 2014 were enrolled in this analysis. Gastrin-stimulated gastric acid secretion was estimated with the endoscopic gastrin test. The association between gastric acid secretion and chronological period was assessed with a multivariate linear regression analysis.

RESULTS

Overall gastric acid secretion gradually increased over the 20-year period in the entire cohort in the unadjusted analysis (p < 0.05). However, the apparent increase was largely related to the relative decreasing rate of H. pylori infection, which profoundly inhibited gastric acid secretion. Gastric acid secretion did not change over the 20-year period in H. pylori-negative subjects, and it showed only a mild increase during this period in H. pylori-positive subjects.

CONCLUSIONS

Considering that gastric acid secretion remained unchanged in H. pylori-negative Japanese men over a 20-year period at a level much lower than that in Occidental subjects, upper gastrointestinal disease profiles in the Japanese population will differ from those in Western countries in the post-H. pylori era.

Serum gastrin and pepsinogens do not correlate with the different grades of severity of gastro-oesophageal reflux disease: a matched case-control study

BACKGROUND

Gastrin and pepsinogens reflect the functional state of the gastric mucosa.

AIM

To evaluate whether serum gastrin and pepsinogens correlate with the different grades of severity of gastro-oesophageal reflux disease (GERD).

METHODS

In all, 388 patients with heartburn not taking any form of acid suppressive therapy were matched-controlled for age and gender and sub-classified into four groups: group 1 non-erosive reflux disease (NERD); group 2, erosive reflux disease (ERD) Los Angeles (LA) A and B, group 3, ERD LA C and D; group 4 Barrett's oesophagus (BO). Fasting serum was analysed for gastrin 17, pepsinogen I, pepsinogen II und Helicobacter pylori using specific EIA tests (GastroPanel; Biohit, Plc).

STATISTICS

Kruskal-Wallis test and analysis of variance.

RESULTS

There was a significant difference among the four groups with respect for pepsinogen I, but not for pepsinogen II, the pepsinogen I pepsinogen II ratio, H. pylori serology and gastrin levels. Pepsinogen I was the lowest in NERD and the highest in BO (median 91.6, mean +/- standard deviation 106.2 +/- 51.6 vs. median 114.7, mean +/- standard deviation 130.4 +/- 70.6; P = 0.046). Pepsinogen I levels were higher in H. pylori positive subjects. After adjusting for H. pylori status, the differences in pepsinogen I across patient groups were no longer statistically significant (P = 0.298).

CONCLUSIONS

Serum gastrin and pepsinogen I and II do not correlate with the different grades of severity of GERD. The non-invasive GastroPanel is not useful for the differentiation of the various forms of GERD.

The relationship between the control of pH and healing and symptom relief in gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GERD) is generally considered to be the result of a motility disorder which permits the abnormal and prolonged exposure of the lumen of the oesophagus to the acidic gastric contents. This view is supported by experimental data, intra-oesophageal pH measurement, and the dramatic results of symptom relief and healing seen with effective antisecretory treatment. Oesophageal mucosal injury is determined by the pH of the refluxate and duration of acid exposure. Most patients experience meal-stimulated reflux during the day and the more severe cases experience 24-h acid exposure. In contrast to the H2-receptor antagonists (H2RAs), the proton pump inhibitors (PPIs) are more effective at controlling meal-stimulated acid secretion when each is given in standard doses. Therefore, the degree and duration of acid suppression throughout 24 h is greater. Treatments which maintain intra-oesophageal pH > 4 for 96% or more of the 24 h normalize acid exposure and are associated with the highest healing rates. Peptic activity is minimized at or above pH 4. The time above pH 4 is significantly longer with the PPIs than with the H2RAs. Thus, the healing-time curves for GERD (grades II-IV) are shifted to the left for the PPIs which heal a significantly greater proportion of patients earlier than the H2RAs or sucralfate. Symptoms in GERD are related to the degree and duration of oesophageal acid exposure. Symptom relief is more rapid and complete with the PPIs than with the H2RAs or other treatments in standard doses.

Low circulating levels of gastrin-17 in patients with Barrett's esophagus

AIM: To examine whether the fasting levels of serum gastrin-17 (G-17) are lower in Barrett's esophagus (BE) patients than in non-Barrett controls.

METHODS: Nineteen patients with BE (presenting with a tubular segment ≥2 cm long in lower esophagus and intestinal metaplasia of incomplete type ("pecialized columnar epithelium") in endoscopic biopsies from the tubular segment below the squamocolumnar junction were collected prospectively from outpatients referred to diagnostic gastroscopy. The controls comprised 199 prospectively collected dyspeptic outpatients without BE or any endoscopically visible lesions in the upper GI tract. Fasting levels of serum G-17 (G-17fast) were assayed with an EIA test using a Mab highly specific to amidated G-17. None of the patients and controls received therapy with PPIs or other antisecretory agents.

RESULTS: The mean and median levels of G-17fast in serum were significantly lower (P = 0.001) in BE patients than in controls. The positive likelihood ratios (LR+) of low G-17fast to predict BE in the whole study population at G-17fast levels <0.5, <1, or <1.5 pmol/L were 3.5, 3.0, and 2.8, respectively. Among patients and controls with healthy stomach mucosa, the LR+ were 5.6, 3.8, and 2.6, respectively. In the whole study population, serum G-17 was below 2 pmol/L in 15 of 19 BE patients (79%). The corresponding prevalence was 66 of 199 (33%) in controls (P<0.001). The G-17fast was 5 pmol/L or more in only one of the 19 BE patients (5%). In controls, 76 of the 199 patients (38%) had such high serum G-17fast levels (P<0.01).

CONCLUSION: Serum levels of G-17fast tend to be lower in native patients with BE than in healthy controls.

The prevalence of Helicobacter pylori infection and the status of gastric acid secretion in patients with Barrett's esophagus in Japan

OBJECTIVES

The acidity of the refluxate into the esophagus is a key factor for the pathogenesis of gastroesophageal reflux disease. Helicobacter pylori (H. pylori) infection can influence gastric acid secretion. We have reported that H. pylori infection prevents reflux esophagitis by decreasing gastric acid secretion in Japanese patients, but the role of this organism in Barrett's esophagus is unclear. The aim of this study was to investigate the prevalence of H. pylori infection and gastric acid secretion in Japanese patients with reflux esophagitis with or without Barrett's esophagus.

METHODS

We enrolled 112 reflux esophagitis patients who were examined for the status of H. pylori and acid secretion in this study. They were divided into three groups, according to the presence or absence of Barrett's esophagus as follows: reflux esophagitis group without Barrett's esophagus (reflux esophagitis alone) (80 patients); short-segment Barrett's esophagus group (16 patients); and long-segment Barrett's esophagus group (LSBE) (16 patients). Age- and sex-matched control subjects were also assigned to the 80 patients with reflux esophagitis alone. The prevalence of H. pylori infection was determined by histology, rapid urease tests, and serum IgG antibodies. Gastric acid secretion was evaluated by the endoscopic gastrin test (EGT).

RESULTS

The overall prevalence of H. pylori infection in the reflux esophagitis patient group (24.1%) was significantly lower than the control group (71.2%) (odds ratio 0.13, 95% confidence interval 0.07-0.24; p < 0.0001). The prevalence of H. pylori infection in the patients with Barrett's esophagus tended to be lower than that in the patients with reflux esophagitis alone (reflux esophagitis alone; 30.0%, SSBE; 18.7%, LSBE; 0%), especially in the patients with LSBE compared with the reflux esophagitis alone group (p < 0.01). The EGT value of the respective reflux esophagitis patient group was significantly higher than the control group. The EGT value in the patients with Barrett's esophagus tended to be higher than that in the patients with reflux esophagitis alone, but the difference was not statistically significant. When examined in H. pylori-negative subjects, no difference was found in the EGT value between the control subjects and the patients with reflux esophagitis alone, but it was significantly higher in patients with Barrett's esophagus than the control subjects (p < 0.05). On the other hand, when examined in the H. pylori-positive subjects, the EGT value was significantly higher in the patients with reflux esophagitis alone than in the control subjects (p < 0.01).

CONCLUSIONS

H. pylori infection may play a protective role in the development of Barrett's esophagus, especially in the development of LSBE in Japan. Gastric acid hypersecretion may be concerned with the development of Barrett's esophagus in addition to the absence of H. pylori infection.

Barrett's oesophagus: optimal strategies for prevention and treatment

Barrett's oesophagus is a change in the lining of the distal oesophagus recognised at endoscopy and documented to have intestinal metaplasia by biopsy. It is thought that it is an acquired condition resulting from chronic gastro-oesophageal reflux disease (GORD). Barrett's oesophagus has the potential to progress to adenocarcinoma of the oesophagus. Evidence to support the association between Barrett's oesophagus and GORD appears to be strong but circumstantial. The intermediate steps that lead from GORD to Barrett's oesophagus are speculative and the timeline for the development of this condition remains obscure. It has yet to be demonstrated that erosive oesophagitis is a necessary intermediate step for the development of Barrett's oesophagus. In spite of effective therapy, documentation that medical or surgical therapy prevents Barrett's oesophagus is lacking. The goal of screening for Barrett's oesophagus is ultimately to improve the survival of patients with adenocarcinoma of the oesophagus. This goal has not been achieved and the evidence-based criteria for screening remain to be defined. Medical and surgical therapy of Barrett's oesophagus is effective in controlling reflux, although not proven to prevent neoplastic progression of the at risk mucosa. Endoscopic techniques of mucosal injury have been applied as alternatives to oesophagectomy in efforts to prevent progression to cancer. Surveillance endoscopy and biopsy is the currently accepted method aimed at early intervention and improved survival for oesophageal adenocarcinoma. A working surveillance protocol to accomplish this is proposed based on dysplasia grade. If no dysplasia is found and confirmed with subsequent endoscopy and biopsy, a 3-year interval is recommended. If only low grade dysplasia is confirmed, then annual endoscopy until no dysplasia is recognised is recommended. On the basis of defined risk factors, high grade dysplasia can lead to intense surveillance every 3 months or an intervention. Future developments in understanding the biology of Barrett's oesophagus and in therapeutic interventions will provide an opportunity for more effective screening, surveillance and prevention of neoplastic progression.

Meal-stimulated gastric acid secretion and integrated gastric acidity in gastro-oesophageal reflux disease

BACKGROUND

No current methods exist to determine meal-stimulated gastric acid secretion in humans under conditions that approximate those of daily living with the ingestion of breakfast, lunch and dinner.

METHODS

Gastric and oesophageal pH were measured in 26 healthy subjects and in 59 subjects with gastro-oesophageal reflux disease. Meal-stimulated gastric acid secretion was calculated from the buffer capacity of the meals determined in vitro and from the time required for the gastric pH to decrease to pH 2 in vivo following ingestion of the meal.

RESULTS

There was a significant correlation between gastric secretion with each meal and the corresponding post-prandial integrated gastric acidity. There was also a significant correlation between meal-stimulated gastric secretion and integrated gastric acidity from 09.00 to 22.00 h in both subjects with gastro-oesophageal reflux disease and controls. In subjects with gastro-oesophageal reflux disease, gastric secretion and integrated gastric acidity from 09.00 to 22.00 h were significantly higher than those in controls. There was a significant correlation between oesophageal acidity and integrated gastric acidity from 09.00 to 22.00 h in subjects with gastro-oesophageal reflux disease.

CONCLUSIONS

As post-prandial gastric acidity is increased in subjects with gastro-oesophageal reflux disease, it seems likely that increased gastric acidity is an important aetiological factor in this disease.

Cisapride inhibits meal-stimulated gastric acid secretion and post-prandial gastric acidity in subjects with gastro-oesophageal reflux disease

BACKGROUND AND AIMS

KCNQ1 potassium channels in human gastric parietal cells are thought to be involved in gastric acid secretion. As cisapride can inhibit similar channels in other tissues and is an effective treatment for nocturnal heartburn, we examined the effects of cisapride on gastric and oesophageal acidity, gastric emptying and heartburn severity in subjects with gastro-oesophageal reflux disease.

METHODS

Subjects (n = 11) had suffered from heartburn four times or more per week for at least 6 months. Gastric pH and oesophageal pH were measured before, during and after a standard meal ingested over 15 min. Each subject received placebo or 10 mg cisapride orally, 30 min before the beginning of the meal. Meal-stimulated gastric acid secretion was calculated from the amount of HCl required to titrate the homogenized standard meal to pH 2 in vitro and the time required for the pH of the ingested meal to decrease to pH 2 in vivo. Heartburn severity was assessed at 15-min intervals beginning at the end of the meal. Gastric emptying of solids was measured using a [(13)C]-octanoic acid breath test.

RESULTS

Cisapride significantly decreased meal-stimulated gastric acid secretion by 20%, decreased integrated gastric and oesophageal acidity by 50-60% and transiently increased the expiration of (13)CO(2). Cisapride did not significantly alter heartburn severity.

CONCLUSIONS

The cisapride-induced decreases in meal-stimulated gastric acid secretion, gastric acidity and oesophageal acidity in subjects with gastro-oesophageal reflux disease can account for its beneficial clinical effects. These results also raise the possibility that gastric KCNQ1 potassium channels are important in meal-stimulated gastric acid secretion and possibly in the pathophysiology of gastro-oesophageal reflux disease.

Results of the Collis-Nissen gastroplasty to control reflux disease in patients who have Barrett's esophagus

Barrett's esophagus is an end-stage gastroesophageal reflux complication with a potential for malignant transformation. This condition probably is involved in esophageal cancer being perceived today as the most rapidly increasing cancer in Western countries. Numerous observations suggest that standard antireflux operations fail over time because of long-term inflammatory and fibrotic changes in the esophageal wall that cause shortening of the esophagus. The addition of esophageal elongation by gastroplasty provides a reliable repair by creation of a tension-free repair, whereas the durable antireflux effects are provided by the total fundoplication around the neoesophagus. The restored LES tone further helps control the mucosal damage and the chronic inflammatory changes. Complete regression of the abnormal mucosa still does not occur, and persistent irritation of that mucosa still entails the risk for progression toward dysplasia. The natural history of the columnar-lined mucosa in BE may be altered by medical or surgical intervention. It is too early to judge in which settings these interventions will be meaningful.

Synergy between low-dose ranitidine and antacid in decreasing gastric and oesophageal acidity and relieving meal-induced heartburn

BACKGROUND

The pathophysiology of recurrent postprandial heartburn and the basis for the effectiveness of antacids or low doses of histamine H2-receptor antagonists have not been well studied.

METHODS

The selected subjects (n=26) had heartburn more than four times a week for at least 2 months, which was responsive to antacids. Gastric pH and oesophageal pH were measured for 1 h before, during, and 4.5 h after ingestion of a meal over 0.5 h. Heartburn severity was assessed at 15-min intervals beginning at the end of the meal. Each subject randomly received placebo, 75 mg ranitidine, 420 mg calcium carbonate, and ranitidine plus calcium carbonate. Values for pH were converted to acid concentration (mM) and integrated acidity was calculated from the cumulative, time-weighted means of the acid concentrations for every second of the postprandial recording period.

RESULTS

There was a close temporal relationship between heartburn and oesophageal acidity. Most oesophageal acid exposure occurred over a 90-min period that began approximately 45 min after the end of the meal. During this period the gastric acid concentration was less than 5% of maximal. Ranitidine significantly decreased gastric but not oesophageal acidity, whilst antacid significantly decreased oesophageal but not gastric acidity. Ranitidine plus antacid significantly decreased both gastric and oesophageal acidity. Antacid alone and ranitidine plus antacid significantly decreased heartburn severity.

CONCLUSIONS

Determining integrated gastric and oesophageal acidity provides novel information regarding the pathophysiology of meal-induced heartburn as well as the actions of low-dose ranitidine and antacid. For subjects with meal-induced heartburn, treatment with low-dose ranitidine plus antacid is particularly effective in decreasing gastric and oesophageal acidity as well as heartburn severity.

Integrated acidity and the pathophysiology of gastroesophageal reflux disease

OBJECTIVES

The aim of this study was to demonstrate that integrated esophageal and gastric acidity values, calculated from 24-h pH recordings, can provide more precise quantitative temporal data than the conventional pH parameters historically associated with gastroesophageal reflux disease (GERD) investigations.

METHODS

Esophagogastroduodenoscopy results and pH tracings from 20 GERD subjects with > or =10% esophageal acid contact time were studied. Integrated gastric and esophageal acidity were calculated from time-weighted average hydrogen ion concentrations at each second of the 24-h recording period.

RESULTS

Integrated esophageal acidity correlated with grade of esophagitis. Two quite distinct GERD subtypes were identified, with either a monophasic or biphasic pattern of integrated esophageal acidity. "Biphasic" subjects differed from "monophasic" subjects in terms of magnitude and pattern of integrated esophageal acidity. Although both groups had significant integrated nocturnal gastric acidity, only the biphasic GERD subjects had concomitant increases in nocturnal integrated esophageal acidity. Esophagitis grade was correlated with magnitude rather than pattern of integrated esophageal acidity, and it was possible to calculate a reflux coefficient that seems to provide an estimate of the quantitative motor disturbance present in GERD.

CONCLUSIONS

Integrated esophageal and gastric acidity provide quantitative measures of GERD pathophysiology and, compared to conventional pH parameters, should enhance evaluation of therapeutic interventions.

Pathogenesis of gastroesophageal reflux and Barrett esophagus

Barrett esophagus is a metaplastic condition that affects the lower esophagus and is a complication of gastroesophageal reflux disease (GERD). Under normal circumstances, the reflux of gastric contents into the esophagus is prevented by a complex barrier at the esophagogastric junction. Dysfunction of the lower esophageal sphincter and the presence of a hiatal hernia lead to failure of this barrier. Esophageal mucosal damage results from the chronic exposure of the esophageal mucosa to gastroduodenal contents and the lack of an effective mucosal defense. This article is an overview of the dysfunction of the esophagogastric junction that leads to GERD. The role of the contents of the reflux and that of Helicobacter pylori infection in the pathogenesis of Barrett esophagus are also summarized.

Pathogenesis of gastroesophageal reflux and Barrett esophagus

Barrett esophagus is a metaplastic condition that affects the lower esophagus and is a complication of gastroesophageal reflux disease (GERD). Under normal circumstances, the reflux of gastric contents into the esophagus is prevented by a complex barrier at the esophagogastric junction. Dysfunction of the lower esophageal sphincter and the presence of a hiatal hernia lead to failure of this barrier. Esophageal mucosal damage results from the chronic exposure of the esophageal mucosa to gastroduodenal contents and the lack of an effective mucosal defense. This article is an overview of the dysfunction of the esophagogastric junction that leads to GERD. The role of the contents of the reflux and that of Helicobacter pylori infection in the pathogenesis of Barrett esophagus are also summarized.

Failure of oesophageal acid control in candidates for Barrett's oesophagus reversal on a very high dose of proton pump inhibitor

BACKGROUND

Normalization of oesophageal acid exposure using high dose proton pump inhibitors in patients who are candidates for ablation therapy has been suggested to be essential for successful Barrett's reversal. However, the success rate for achieving pH normalization has not been determined.

METHODS

Patients with Barrett's oesophagus (2-6 cm in length) who were found to be eligible for ablation therapy using multipolar electrocoagulation were included in this prospective study. Patients underwent an upper endoscopy to determine Barrett's length and other anatomic characteristics. Biopsies were obtained to rule out dysplasia. Subsequently, patients were treated with omeprazole 40 mg b.d. Twenty-four hour oesophageal pH monitoring was performed after a mean period of 8.4 +/- 0.6 days of therapy.

RESULTS

Twenty-five patients were enrolled into the study. The pH test was abnormal in four (16%) of the study subjects. An additional two (8%) patients had abnormal supine percentage time with pH less than 4. There was no significant difference in oesophageal acid control between patients with long vs. short segment Barrett's oesophagus. Elderly (> 60 years) patients tended to have less acid control than younger (</= 60 years) patients.

CONCLUSIONS

Failure of oesophageal acid control in candidates for Barrett's oesophagus reversal on very high dose of proton pump inhibitor is not uncommon. Our study suggests that ambulatory 24-h oesophageal pH monitoring should be considered in all candidates for Barrett's reversal who are treated with high dose proton pump inhibitor to ensure normalization of oesophageal acid exposure.

Gastroesophageal Reflux Disease

Prior to the advent of proton pump inhibitors, internists recommended antireflux surgery primarily for patients whose gastroesophageal reflux disease (GERD) failed to respond to medical therapy. Although many physicians still cling to the notion that antireflux surgery is a procedure best reserved for "medical failures," today this position is inappropriate. Modern medical treatments for GERD are extraordinarily effective in healing reflux esophagitis. It is uncommon to encounter patients with heartburn or esophagitis due to GERD who do not respond to aggressive antisecretory therapy. Indeed, the very diagnosis of GERD must be questioned for patients whose esophageal signs and symptoms are unaffected by the administration of proton pump inhibitors in high dosages. In the large majority of these so-called refractory patients, protracted esophageal pH monitoring reveals good control of acid reflux by the proton pump inhibitors. This finding indicates that the persistent symptoms usually are not due to acid reflux, but to other problems such as functional bowel disorders. Medical treatment fails in such patients because the diagnosis is mistaken, not because the drugs fail to control acid reflux. Modern antireflux surgery also is highly effective for controlling acid reflux, but fundoplication will not be effective for relieving symptoms in patients whose symptoms are not reflux-induced. Therefore, many patients deemed failures of modern medical therapy would be surgical failures as well. Antireflux surgery is an excellent treatment option for patients with documented GERD who respond well to medical therapy, but who wish to avoid the expense, inconvenience, and theoretical risks associated with lifelong medical treatment. Ironically, surgical therapy for GERD today is best reserved for patients who are medical successes.

Gastric acid and pepsin secretion in patients with Barrett's esophagus and appropriate controls

The objective of this study was to determine whether gastric secretion of acid and pepsin is different in the subset of esophagitis patients who also have Barrett's esophagus. Basal and stimulated gastric secretions were studied for 1 hr in the unstimulated state and 1 hr after pentagastrin 6 microg/kg subcutaneous injection. Because Barrett's patients are predominantly male, the 30 patients were matched with patients who had esophagitis, but not Barrett's, for sex (26 men, 4 women) and age as well as for background gastrointestinal disease (duodenal ulcer in 10, no ulcer disease in 17 and Zollinger-Ellison hypersecretors in 3). Patients with Barrett's weighed more than controls (P < 0.05). Acid and pepsin output in the basal and stimulated state were no different in Barrett's and their appropriately matched controls. Overnight fasting residue--volume, pH, acid and pepsin concentrations, and bile content--were also alike. The severity of esophagitis or prevalence of esophageal ulcer or stricture was not different between those with and without Barrett's and in neither was the grade of esophagitis related to acid or pepsin output. It is concluded that Barrett's esophagus patients do not have gastric secretions different from appropriately matched controls with esophagitis alone. When present, esophagitis due to reflux in Barrett's epithelium should be treated on its merits by appropriate reduction of acid exposure.

Time pattern of gastric acidity in Barrett's esophagus

Increased gastroesophageal acid reflux is frequently found in patients with Barrett's esophagus, and it has been hypothesized that gastric acid hypersecretion could be an important factor aggravating the exposure of esophageal mucosa to acid and then contributing to the development of this disorder. The aim of the present study was to assess whether the circadian pattern of gastric acidity differs between refluxer patients with and without Barrett's esophagus and normal subjects. Continuous 24-hr gastric pH monitoring was performed in 119 healthy volunteers, 20 patients with Barrett's esophagus, 37 patients with moderate and 10 patients with severe reflux esophagitis without Barrett's esophagus. In all these diseases the final diagnosis was ascertained by means of endoscopy plus biopsy. There was no difference in the 24-hr and daytime patterns of gastric pH between healthy subjects and patients with Barrett's esophagus, while nocturnal acidity was significantly lower (P < 0.05) in the latter population. Gastric acidity, in contrast, was higher (P < 0.05) in controls than in patients with both moderate and severe reflux esophagitis without Barrett's esophagus during the whole 24-hr period. There was no difference between refluxer patients with and without Barrett's esophagus in any of the three time intervals we analyzed. Because normal subjects had lower gastric pH than patients with Barrett's esophagus during the night and than patients with reflux esophagitis during the whole 24-hr period, gastric hyperacidity is not a relevant factor in the development of both metaplastic columnar epithelium and inflammatory changes in the distal esophagus, and other pathophysiological mechanisms are involved in these histological alterations.

Ranitidine therapy in patients with idiopathic gastric acid hypersecretion. A prospective study

One hundred twenty-four patients with idiopathic gastric acid hypersecretion (basal acid output greater than 10.0 meq/hr) were prospectively evaluated and treated with ranitidine twice a day. Fifty-four patients (44%) required standard doses of ranitidine 300 mg/day for adequate treatment, and the other 70 patients (56%) required increased doses of ranitidine (mean 994 mg/day, range 600-3000 mg/day). Mean basal acid outputs for these two groups were 14.0 and 16.6 meq/hr, respectively, which were not significantly different. Nevertheless, there was a significant correlation between basal acid output and daily ranitidine dose required for therapy (r = 0.18, P = 0.05). The duration of ranitidine therapy consisted of: < 1 year (N = 46), 1 year (N = 16), 2 years (N = 19), 3 years (N = 22), 4 years (N = 15), 5 years (N = 6). Only five patients required progressive increases in ranitidine during the time of treatment, which consisted of an average of 0.5 dose adjustments per year. No side effects occurred with any of these high doses of ranitidine. These results indicate that, as in Zollinger-Ellison syndrome, ranitidine is effective therapy for patients with idiopathic gastric acid hypersecretion; however, markedly increased doses as large as 3000 mg/day may be required.

Pharmacological management of gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GORD) ranges from episodic symptomatic reflux without oesophagitis to severe oesophageal mucosal damage, such as Barrett's metaplasia or peptic stricture. The multifactorial pathogenesis of GORD prevents medical cure of the disease. GORD is a chronic disease with a high tendency to relapse, requiring a long term treatment strategy in practically all patients. Complete healing of all mucosal lesions is not necessarily the aim of treatment in all patients. In milder forms of reflux disease, symptom relief is the most important goal. Many patients with mild GORD do well on symptomatic self-care with antacids and/or alginate. In addition, lifestyle changes should be advised to all patients: these improve symptoms and enhance the efficacy of therapy. In the acute treatment of GORD the prokinetic drug cisapride has been shown to be effective in relieving symptoms and healing grade I to II oesophagitis. Cisapride decreases symptomatic and endoscopic relapse in patients with mild GORD. Histamine H2-receptor antagonists are effective in relieving reflux symptoms in about 50% of patients, but with regard to healing, H2-antagonists appear to be mainly effective in grades I and II and not in higher grades of oesophagitis. Maintenance treatment with H2-antagonists is mainly symptomatically effective in patients with mild GORD. Proton pump inhibitors (PPIs) provide significantly higher healing rates of reflux oesophagitis than H2-antagonists, even in the more severe cases of oesophagitis and Barrett's ulcers. PPIs are also effective in patients with oesophagitis refractory to treatment with H2-antagonists. PPIs have become the drugs of first choice in healing of all patients with more severe forms of reflux oesophagitis, and increasingly also for patients with milder forms of oesophagitis, certainly those who fail to respond to other drugs. In maintenance treatment of GORD, PPIs are the most effective drugs, offering the possibility of keeping nearly all patients in remission with adjusted doses. Current patient data of up to 5 years indicate the safety of this strategy for this period, but the exact consequences of strong acid inhibition over a longer period still have to be clarified. At present, all but a few patients with GORD can be managed adequately by medical therapy.

Changing patterns in the treatment of carcinoma of the esophagus

BACKGROUND

Decision-making in esophageal carcinoma. Treatment of carcinoma of the esophagus knows a great variety of modalities, ranging from simple palliative endoscopic pertubation to extensive curative operations.

METHODS

Retrospective review.

RESULTS

The three main groups of tumors are squamous cell carcinoma related to alcohol and tobacco abuse; adenocarcinoma in Barrett's esophagus related to long-standing gastroesophageal reflux; and adenocarcinoma of the cardia the origin of which is still unknown. Dysphagia and retrosternal pain are not only the most important symptoms but also the most important factors regarding survival. Diagnosis is made by endoscopy and biopsy. In the pretreatment staging a careful selection of the great variety of available diagnostic tools should be made. The ever-increasing diversity of local palliative procedures: tubing, photoablation, brachytherapy all have their place, but should not be allowed to distract us from the fact that surgery is the only hope for cure in these patients. Surgery should only be performed with curative intent and even then the long-term results are modest, with a 5-year survival of about 40% in node-negative and 18% in node-positive patients.

CONCLUSION

In patients with carcinoma of the esophagus a polydisciplinary treatment approach is mandatory.

Idiopathic gastric acid hypersecretion. Comparison with Zollinger-Ellison syndrome

Many patients with acid-peptic disease have idiopathic gastric acid hypersecretion defined as a basal acid output > 10.0 meq/hr; however, a significant proportion have basal acid outputs > 15.0 meq/hr, which is within the range found in Zollinger-Ellison syndrome. Although idiopathic gastric acid hypersecretion is more common than Zollinger-Ellison syndrome, it is important that these two disorders be differentiated because of differences in treatment and natural history. In the present study, we compared 124 patients with idiopathic gastric acid hypersecretion and 137 patients with Zollinger-Ellison syndrome. There were no significant differences with regard to age at diagnosis, history of upper gastrointestinal hemorrhage, nausea, vomiting, and family history of duodenal ulcer and other acid-peptic disease. However, significant differences were observed between patients with idiopathic gastric acid hypersecretion and patients with Zollinger-Ellison syndrome with regard to percentage of males: 77% compared to 64% (P = 0.008), mean serum gastrin: 60 pg/ml compared to 3679 pg/ml (normal < 100 pg/ml) (P < 0.001), mean basal acid output: 15.4 meq/hr compared to 47.0 meq/hr (P < 0.001), mean age at onset of symptoms: 33 years compared to 41 years (P < 0.001), mean duration of symptoms before diagnosis: 11 years compared to five years (P < 0.001), percentage with abdominal pain: 67% compared to 82% (P = 0.00004), percentage with diarrhea: 12% compared to 75% (P < 0.000001), percentage with pyrosis: 58% compared to 40% (P = 0.003), percentage with duodenal ulcer: 53% compared to 74% (P < 0.000001), and percentage with esophagitis: 31% compared to 42% (P = 0.0004).(ABSTRACT TRUNCATED AT 250 WORDS)

Basal acid output and gastric acid hypersecretion in gastroesophageal reflux disease. Correlation with ranitidine therapy

The purpose of this study was to evaluate possible differences in basal gastric acid secretion with regard to severity of gastroesophageal reflux disease. Basal acid output was determined by nasogastric suction in 228 patients with gastroesophageal reflux disease who received upper gastrointestinal endoscopy and were diagnosed with either pyrosis alone (N = 98), erosive esophagitis with or without pyrosis (N = 87), or Barrett's esophagus (N = 43). Mean basal acid output for the 228 patients with gastroesophageal reflux disease was 6.5 +/- 5.6 meq/hr, which was significantly different from 65 normal subjects with a mean basal acid output of 3.0 +/- 2.7 meq/hr (P < 0.0001). Compared to normal subjects, mean basal acid outputs significantly differed for patients with pyrosis (P < 0.05), esophagitis (P < 0.01), and Barrett's esophagus (P < 0.01). There was also a significant difference in mean basal acid output between the patients with pyrosis and Barrett's esophagus (P < 0.01). Nineteen of the 98 patients with pyrosis (19%), 24 of the 87 patients with esophagitis (28%), and 15 of the 43 patients with Barrett's esophagus (35%) had gastric acid hypersecretion (basal acid output greater than 10.0 meq/hr). One hundred forty-six patients with gastroesophageal reflux disease were treated with ranitidine in doses that resulted in complete healing of esophagitis and disappearance of pyrosis. Ninety-three patients responded to ranitidine 300 mg/day; however, 53 patients required increased dose of ranitidine (mean 1205 mg/day, range 600-3000 mg/day).(ABSTRACT TRUNCATED AT 250 WORDS)

Barrett's esophagus: pathogenesis, epidemiology, functional abnormalities, malignant degeneration, and surgical management

Barrett's esophagus (i.e. columnar epithelial metaplasia in the distal esophagus) is an acquired condition that in most patients results from chronic gastroesophageal reflux. It is a disorder of the white male in the Western world with a prevalence of about 1/400 population. Due to the decreased sensitivity of the columnar epithelium to symptoms, Barrett's esophagus remains undiagnosed in the majority of patients. Gastroesophageal reflux disease in patients with Barrett's esophagus has a more severe character and is more frequently associated with complications as compared with reflux patients without columnar mucosa. This appears to be due to a combination of a mechanically defective lower esophageal sphincter, inefficient esophageal clearance function, and gastric acid hypersecretion. Excessive reflux of alkaline duodenal contents may be responsible for the development of complications (i.e., stricture, ulcer, and dysplasia). Therapy of benign Barrett's esophagus is directed towards treatment of the underlying reflux disease. Barrett's esophagus is associated with a 30- to 125-fold increased risk for adenocarcinoma of the esophagus. The reasons for the dramatic rise in the incidence of esophageal adenocarcinoma, which occurred during the past years, are unknown. High grade dysplasia in a patient with columnar mucosa is an ominous sign for malignant degeneration. Whether an esophagectomy should be performed in patients with high grade dysplasia remains controversial. Complete resection of the tumor and its lymphatic drainage is the procedure of choice in all patients with a resectable carcinoma who are fit for surgery. In patients with tumors located in the distal esophagus, this can be achieved by a transhiatal en-bloc esophagectomy and proximal gastrectomy. Early adenocarcinoma can be cured by this approach. The value of multimodality therapy in patients with advanced tumors needs to be shown in randomized prospective trials.

Comparison of omeprazole and ranitidine in treatment of refractory gastroesophageal reflux disease in patients with gastric acid hypersecretion

Secretion of gastric acid and volume, serum gastrin concentration, and ambulatory 24-hr esophageal pH monitoring were evaluated prospectively in 12 patients with idiopathic gastric acid hypersecretion (basal acid output greater than 10.0 meq/hr) undergoing treatment for refractory chronic long-standing pyrosis. Treatment lasted six months and consisted of three months of ranitidine (mean 2150 mg/day, range 1200-3000 mg/day), followed by three months of omeprazole (mean 33 mg/day, range 20-60 mg/day). Both ranitidine and omeprazole significantly reduced gastric acid output (P less than 0.001) and gastric volume output (P less than 0.001) compared to a basal evaluation and resulted in complete disappearance of pyrosis. Total reflux time (percent 24 hr intraesophageal pH less than 4) was significantly reduced by ranitidine (P less than 0.02) and omeprazole (P less than 0.001) compared to basal evaluation; however, the effects of omeprazole were significantly greater than ranitidine (P less than 0.05). Omeprazole caused a significant increase in serum gastrin concentration compared to both basal and ranitidine (P less than 0.05). Endoscopically documented erosive esophagitis was present in nine of the 12 patients, and seven of the 12 patients had Barrett's epithelium. All 12 patients had complete resolution of pyrosis and healed esophagitis by six months, but no significant endoscopic regression was observed in the extent of Barrett's epithelium. No side effects occurred with these high doses of ranitidine or omeprazole. These results indicate that high-dose ranitidine and omeprazole are effective therapy for refractory gastroesophageal reflux disease. However, with omeprazole, total reflux times are reduced more than with ranitidine, often into the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

Medical therapy for gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) remains a ubiquitous problem, although therapeutic options continue to evolve. Effective therapy calls for understanding the pathogenesis. Key factors associated with GERD include incompetence of the lower esophageal sphincter, esophageal clearance, gastric contents, tissue resistance, and potency of the refluxate. Phase-type directed therapy remains the best treatment approach and histamine (H2)-receptor antagonists are now the cornerstone of therapy for patients not responsive to conservative measures. In a subset of patients with severe esophagitis who do not respond to conventional H2-receptor antagonist therapy, efficacy has been demonstrated with high-dose therapy. The acid suppressant omeprazole, highly effective in erosive esophagitis, is the drug of choice for esophagitis resistant to H2-receptor antagonists. Despite effective forms of therapy, relapse rates are high in patients with severe GERD, and maintenance therapy typically is required. With near uniformity, efficacy end points for these agents have been directed toward relief of heartburn, regurgitation, and dyspepsia. Few data exist correlating relief of GERD and improvement of chest pain. Although therapeutic strategies for treating GERD have improved, empiric treatment of suspected GERD in the patient with noncardiac chest pain does not appear to be the optimal approach and should be reserved for cases where diagnostic testing is limited or unavailable.

Definition for idiopathic gastric acid hypersecretion. A statistical and functional evaluation

Zollinger-Ellison syndrome and other gastric acid hypersecretory states in which a specific etiology is identified are defined as a basal acid output of greater than 15.0 meq/hr. To determine the level of basal acid output that defines idiopathic gastric hypersecretion, basal acid outputs were investigated in normal subjects and patients with duodenal ulcers, and functional and statistical definitions for idiopathic gastric acid hypersecretion were developed. Sixty-five normal subjects were evaluated to define idiopathic gastric acid hypersecretion on a statistical basis, and 22 patients with refractory duodenal ulcers were evaluated to define idiopathic gastric acid hypersecretion on a functional basis. Mean basal acid output for the 65 normal subjects was 3.0 +/- 2.7 meq/hr. Even though the mean basal acid output for the group of 28 normal male subjects was slightly higher than for the group of 37 normal female subjects, the groups were not significantly different. The 95% confidence interval around the mean basal acid output for all normal subjects was 2.4-3.7 meq/hr, with little difference between the male and female groups. The mean basal acid output plus two standard deviations and the mean basal acid output plus three standard deviations for the 65 normal subjects were 8.4 meq/hr and 11.1 meq/hr, respectively. Of 109 patients with active duodenal ulcers treated for eight weeks with standard doses of antisecretory medication, 22 showed no healing as documented by endoscopy.(ABSTRACT TRUNCATED AT 250 WORDS)