Replacement of oral proton pump inhibitors with intravenous pantoprazole to effectively control gastric acid hypersecretion in patients with Zollinger-Ellison syndrome

OBJECTIVES: In patients with Zollinger-Ellison syndrome (ZES) or other conditions requiring oral doses of proton pump inhibitors, it frequently becomes necessary to use parenterally administered gastric acid inhibitors. However, i.v. histamine-2 receptor antagonists are not effective at usual doses and lose their effectiveness because of tachyphlaxis. With the approval in the United States of i.v. pantoprazole, a substituted benzimidazole available in i.v. formulation, it will become possible to acutely manage gastric acid secretion in the acute care setting of a hospital. This study was developed to monitor the safety and establish the efficacy of i.v. pantoprazole as an alternative to oral proton pump inhibitors for the control of gastric acid hypersecretion in patients with ZES. METHODS: The efficacy of replacing oral PPI therapy with i.v. pantoprazole was evaluated in 14 ZES patients. After study enrollment, patients taking their current doses of oral PPI (omeprazole or lansoprazole) were switched to pantoprazole i.v. for 6 days during an 8-day inpatient period in the clinical research center. Effective control was defined as an acid output (AO) of < 10 mEq/h (< 5 mEq/h in patients with prior gastric acid-reducing surgery). RESULTS: The mean age of the 14 patients enrolled in the study was 52.4 yr (range = 38-67). Mean basal AO was 0.55 +/- 0.32 mEq/h and mean fasting gastrin was 1089 pg/ml (range = 36-3720). Four patients were also diagnosed with the multiple endocrine neoplasia type I syndrome, nine were male, and two had previously undergone acid-reducing surgery. Before study enrollment, gastric acid hypersecretion was controlled in nine of 14 patients with omeprazole (20-200 mg daily) and five of 14 with lansoprazole (30-210 mg daily). In the oral phase of the study all patients had adequate control of gastric acid secretion, with a mean AO of 0.55 +/- 0.32 mEq/h (mean +/- SEM). Thereafter, 80 mg of i.v. pantoprazole was administered b.i.d. for 7 days by a brief (15 min) infusion and the dose was titrated upward to a predetermined maximum of 240 mg/24 h to control AO. A dose of 80 mg b.i.d. of i.v. pantoprazole controlled AO in 13 of 14 of the patients (93%) for the duration of the study (p > 0.05 compared to baseline values for all timepoints). One sporadic ZES patient (oral control value = 0.65 mEq/h on 100 mg of omeprazole b.i.d. p.o.) was not controlled with 80 mg of i.v. pantoprazole b.i.d. and dosage was titrated upward to 120 mg b.i.d. after day 2. CONCLUSIONS: There were no serious adverse events observed. Intravenous pantoprazole provides gastric acid secretory control that is equivalent to the acid suppression observed with oral proton pump inhibitors. Most ZES patients (93%) maintained effective control of AO previously established with oral PPIs when switched to 80 mg of i.v. pantoprazole b.i.d.; however, for difficult-to-control patients, doses > 80 mg b.i.d. may be required.     

Maintenance oral pantoprazole therapy is effective for patients with Zollinger-Ellison syndrome and idiopathic hypersecretion

OBJECTIVE: Maintenance proton pump inhibitor (PPI) therapy is effective for gastric acid hypersecretory states, although data with pantoprazole are limited. The aim of this study was to evaluate the safety and efficacy of long term p.o. pantoprazole in individuals with hypersecretion. METHODS: All subjects had Zollinger-Ellison syndrome or idiopathic hypersecretion. Baseline acid output was measured in the presence of prior maintenance antisecretory therapy before pantoprazole exposure. The starting dose was 40 mg b.i.d. in most cases, and the dose was adjusted to document control within the first 2 wk of therapy. The maximal allowable dose was 240 mg daily. Acid output was measured on day 28 and then quarterly from month 3. The primary efficacy endpoint was documented control of acid secretion at 6 months, i.e., acid output in the last 1 h before the next dose of therapy of <10 mEq/h (<5 mEq/h in subjects with prior acid-reducing surgery). RESULTS: A total of 26 subjects had Zollinger-Ellison syndrome (six with multiple endocrine neoplasia syndrome type 1) and nine had idiopathic hypersecretion. Pre-enrollment therapy included omeprazole in 27 subjects and lansoprazole in eight, and 82.4% of subjects were controlled on their prior regimens. With upward dose titration, acid output was controlled in all subjects by day 10 and in all but two (6%) at the 6-month time point. Median acid secretion on therapy at 6 months was <2 mEq/h (mean 2.2 mEq/h; range 0-10.5 mEq/h) at a dose of 40 mg b.i.d. for 24 subjects, 80 mg b.i.d. for seven subjects, and 120 mg b.i.d. for two subjects. During the course of the study, five subjects required doses of 240 mg daily. Pantoprazole was generally well tolerated. No cases of anterior optic ischemic neuropathy occurred. Five subjects died during follow-up, all because of events unrelated to the study drug. CONCLUSIONS: Maintenance p.o. pantoprazole therapy at a dose of 80-240 mg/day in divided doses was both effective and generally well tolerated for patients with Zollinger-Ellison syndrome and idiopathic hypersecretion.     

Oral pantoprazole for acid suppression in the treatment of patients with Zollinger-Ellison syndrome.

BACKGROUND: The management of patients with gastric acid hypersecretion due to gastrinoma, usually recognized as Zollinger-Ellison syndrome (ZES), was radically changed 10 years ago by the use of proton pump inhibitors. Surgical treatment now concentrates on tumour excision, and in the majority of patients, gastrectomy is no longer required to prevent complications of acid hypersecretion that can be managed pharmacologically. AIMS: To verify the ability of pantoprazole to control gastric acid hypersecretion and the clinical effects of acid hypersecretion in seven patients with documented ZES. METHODS: Pantoprazole was administered at an initial dose of 80 mg daily for seven days before basal acid output (BAO) was measured at 08:00, ie, 1 h before the next dose of pantoprazole was normally ingested. A lower (40 mg) or higher (120 mg or more) dose of pantoprazole was then used to keep the BAO in the therapeutic range (between 0.1 and 10 mmol/h) and to control clinical symptoms such as acid-related pain or diarrhea. RESULTS: BAO and clinical symptoms were controlled with pantoprazole 40 mg daily in one patient, 80 mg daily in two patients, 120 mg daily in three patients and 160 mg daily in one patient. CONCLUSIONS: Pantoprazole was able to control acid hypersecretion in ZES patients when administered in doses between 40 and 160 mg daily. An initial dose of 120 mg given before further titration of the drug regimen appears to be a reasonable therapeutic strategy.     

Gastric secretion in Zollinger-Ellison syndrome. Correlation with clinical expression, tumor extent and role in diagnosis--a prospective NIH study of 235 patients and a review of 984 cases in the literature

We prospectively studied 235 patients with Zollinger-Ellison syndrome (ZES) (205 without and 30 with prior acid-reducing surgery) and compared the results with 984 patients from 182 reports in the literature. The aims of the study were to evaluate the sensitivity of proposed acid secretory criteria for the diagnosis of ZES, propose new criteria, evaluate the variability and methodology of gastric secretory testing, and correlate the symptoms and signs of ZES, tumor extent, and primary tumor size and location with the degree of gastric acid hypersecretion. Multiple endocrine neoplasia-type 1 (MEN1) occurred in 22% of patients. The mean basal acid output (BAO) in patients without and with prior acid-reducing surgery was 41.2 +/- 1.7 mEq/hr (range, 1.6-118.3 mEq/hr) and 27.6 +/- 3.5 mEq/hr (range 5.9-102.9 mEq/hr), respectively. In patients with MEN1, those with female gender, Hispanic, or Asian race had lower BAOs. Diarrhea, esophageal stricture, and pyloric scarring were associated with a higher BAO. Neither other symptoms nor the tumor extent, primary tumor location, or size correlated with the magnitude of acid hypersecretion. ZES diagnosis was delayed a mean of 5.5 +/- 0.4 yr. Patients who were misdiagnosed as having either Crohn or celiac disease had higher BAOs. The sensitivities from our study and the literature review of the proposed BAO criteria for the diagnosis of ZES in patients without previous gastric acid-reducing surgery were 91% and 90% for BAO > or = 15 mEq/hr, 86% and 82% for BAO > or = 18 mEq/hr, 69% and 67% for BAO > 25 mEq/hr, and < 60% for BAO > 31 mEq/hr, respectively. The specificities of all the proposed BAO criteria were high. Both the criterion of BAO > or = 15 mEq/hr and BAO > or = 18 mEq/hr had good specificities and equal sensitivity. With prior acid-reducing surgery, the sensitivities in our study and from the literature review were 100% and 81% for BAO > or = 5 mEq/hr, 73% and 45% for BAO > 14.4 mEq/hr, and 37% and 31% for BAO > 19.2 mEq/hr, respectively. The reported mean specificity for the criterion of BAO > or = 5 mEq/hr was 85%, while it was 100% for the other 2 criteria. The maximal acid output (MAO) criterion of > 70 mEq/hr had sensitivities in the present National Institutes of Health (NIH) study and the literature review of 39% and 31%, respectively, and the criterion of MAO > 100 mEq/hr had a sensitivity of < 15% in patients with no prior acid-reducing surgery. The proposed criterion of BAO/MAO ratio > 0.6 had a low sensitivity. The proposed criterion of the ratio of basal and maximal acid H+ concentration (BAC/MAC ratio) > or = 0.6 had an excellent sensitivity-- > or = 89% in patients with or without previous acid-reducing surgery. The reported specificity for both the BAO/MAO criterion and the BAC/MAC criterion were similar, but BAC/MAC had a better sensitivity. Combination criteria of BAO generally did not improve sensitivity. The criterion of pH < or = 1 was met by only 27% of patients, and pH < or = 0.96 by 21% of patients with previous acid-reducing surgery. For patients with MEN1 with no prior acid-reducing surgery, the sensitivities were lower compared with patients with the sporadic form of ZES. The mean gastric volume in patients without prior acid-reducing surgery was 314 +/- 10 mL/hr and 247 +/- 25 mL/hr in patients with prior acid-reducing surgery. A basal volume criteria of > 160 mL/hr in patients without prior acid-reducing surgery occurred in > 86% of patients, and > 140 mL/hr in 87% of patients with prior acid-reducing surgery; these, thus, are neglected findings that have good sensitivities. Our analysis shows criteria based on MAO, pH, and BAO/MAO ratio do not have high sensitivities and thus are not useful. In patients without prior acid-reducing surgery, the criteria of BAO > or = 15 mEq/hr, BAC/MAC ratio > or = 0.6, and basal gastric volume > 160 mL/hr are useful for the diagnosis of ZES and have good specificities. In patients with prior acid-reducing surgery, the criteria of BAO > or = 5 mEq/hr, BAC/MAC ratio > or = 0.6, and basal gastric volume > 140 mL/hr have high sensitivities. In patients with sporadic ZES without acid-reducing surgery, the criterion of BAO > or = 18 mEq/hr is recommended as it has a similar sensitivity but higher specificity than the criterion of BAO > or = 15 mEq/hr. Only 1 patient in either data set (NIH or the literature) with or without previous acid-reducing surgery had a basal gastric pH > 2, therefore this finding essentially excludes the diagnosis of ZES. Gastric secretory measurements for 30 minutes, but not 15 minutes, give results comparable to those for a full hour. On the basis of these results, a number of gastric secretory criteria are proposed, including some for the first time, and alterations in methodology are proposed that should prove useful in the diagnosis of ZES.     

Intravenous omeprazole in patients with Zollinger-Ellison syndrome undergoing surgery

Twenty patients with Zollinger-Ellison syndrome who were undergoing surgery were studied prospectively to assess the efficacy and safety of IV omeprazole. During the preoperative period, in 19 of 20 patients, omeprazole 60 mg administered as an IV bolus every 12 hours inhibited acid output to less than 5 mEq/h measured in the last hour before the next dose of drug. In one patient, acid output was 25 mEq/h 12 hours after omeprazole, 60 mg, and increasing the dose to 100 mg every 12 hours reduced acid output to less than 5 mEq/h. During the operative and postoperative periods, IV omeprazole controlled gastric acid hypersecretion in all patients for up to 15 days. During this time, all patients received the dose determined preoperatively. No patient developed any clinical, hematological, or biochemical toxicity that could be attributed to omeprazole therapy during the preoperative or postoperative period. The present study demonstrates that omeprazole administered by IV bolus is safe and effective for controlling gastric acid hypersecretion. In contrast to IV histamine H2-receptor antagonists, IV omeprazole has the advantages of not requiring continuous infusion or postoperative dose adjustments. Intravenous omeprazole will become the drug of choice in patients with Zollinger-Ellison syndrome undergoing surgery.     

Oral and intravenous dosage forms of pantoprazole are equivalent in their ability to suppress gastric acid secretion in patients with gastroesophageal reflux disease

OBJECTIVE: The aim of this study was to assess the ability of pantoprazole to maintain gastric acid suppression in patients with gastroesophageal reflux disease who are switched from an oral (p.o.) to an intravenous (i.v.) dosage form. METHODS: A total of 65 patients with gastroesophageal reflux disease were administered either 40 or 20 mg of p.o. pantoprazole daily for 10 days, then were switched to either a matching dose of i.v. pantoprazole or to placebo for 7 days. Acid output (basal and maximal) was measured at the end of the p.o. treatment period and on the first and last days of i.v. therapy. In the primary efficacy analysis, the acid output values at the end of the p.o. pantoprazole treatment were compared with those at the end of the i.v. treatment. Safety was monitored by periodic vital sign measurements, clinical laboratory evaluations, ophthalmic examinations, electrocardiograms, and reports of adverse events. The data were tested by an analysis of covariance and by Wilcoxon signed rank and t tests. RESULTS: Maximal acid output (mean +/- SD) in the 40 mg and 20 mg pantoprazole group after p.o. treatment was 6.5 +/- 5.6 mEq/h and 14.5 +/- 15.5 mEq/h, respectively; whereas, at the end of the i.v. treatment period, the values were 6.6 +/- 6.3 mEq/h and 11.1 +/- 10.2 mEq/h, respectively. In patients given i.v. placebo, acid output was significantly (p < 0.05) increased to 29.2 +/- 13.0 mEq/h by day 7. Both p.o. and i.v. pantoprazole dosage forms had similar favorable safety and tolerability profiles. CONCLUSIONS: The p.o. and i.v. formulations of pantoprazole (40 and 20 mg) are equivalent in their ability to suppress gastric acid output. The i.v. form of pantoprazole offers an alternative for gastroesophageal reflux disease patients who are unable to take the p.o. formulation.     

Inhibition of pentagastrin-induced gastric acid secretion by intravenous pantoprazole: a dose-response study

OBJECTIVE: The purpose of this study was to compare the gastric acid inhibitory ability of increasing doses of intravenous (i.i.) pantoprazole with that of i.v. famotidine and placebo. Pentagastrin was infused continuously in healthy subjects as a model for patients with Zollinger-Ellison syndrome. METHODS: Pentagastrin (1 microg/kg/h) was infused to stimulate maximum acid output in 39 subjects over a 25-h period. After 60 min of pentagastrin infusion, subjects received a single dose of i.v. pantoprazole (20, 40, 80, or 120 mg), i.v. famotidine (20 mg), or saline placebo. The variables measured were onset of response (time until acid output fell to < 10 mEq/h), duration of response (time acid output remained < 10 mEq/h), and cumulative acid output over 24 h. RESULTS: All doses of i.v. pantoprazole produced a dose-dependent suppression of acid output to < 10 mEq/h. Single i.v. doses of pantoprazole, 80 and 120 mg, suppressed acid output by > 90% in all subjects for < or = 21 h and had an onset of action of < 1 h. CONCLUSIONS: Intravenous pantoprazole has a rapid onset and a clear dose-related effect, with a significantly longer duration of action than that of i.v. famotidine.     

Prospective study of efficacy and safety of lansoprazole in Zollinger-Ellison syndrome

Lansoprazole, a new substituted benzimidazole H⁺, K⁺-ATPase inhibitor, profoundly inhibits gastric acid secretion and has potential use in the management of diseases such as Zollinger-Ellison syndrome (ZES). In the present study we evaluated the efficacy and safety of lansoprazole in controlling acid hypersecretion in 20 patients with ZES. The starting dose was 60 mg once daily. Control of acid hypersecretion was defined as the dose required to reduce acid secretion to <10 meq/hr in the last hour before the next dose. Doses were adjusted upwards until effective control was achieved. Patients not controlled with 120 mg once daily were placed on twice daily lansoprazole. Most patients (90%) required lansoprazole once daily. During long-term follow-up (mean 18.5 months), 25% of patients required upward dose adjustments and 25% of patients required twice daily lansoprazole. Following cessation of therapy, the mean time for gastric acid output to reach half basal acid output was 39.1 hr. Lansoprazole was well-tolerated without side effects. Clinical chemistry and hematological studies were unchanged, and no gastric carcinoids developed. These results demonstrate that lansoprazole is a safe and effective inhibitor of gastric acid hypersecretion in patients with Zollinger-Ellison syndrome. Because it has a long duration of action, lansoprazole can be used to control gastric acid hypersecretion in most patients with Zollinger-Ellison syndrome using a once daily dosing schedule.     

Effect of pantoprazole versus other proton pump inhibitors on 24-hour intragastric pH and basal acid output in Zollinger-Ellison syndrome

AIM: In this open prospective study, the efficacy of pantoprazole in reducing gastric acid secretion in Zollinger-Ellison syndrome patients was compared to that obtained previously with other proton pump inhibitors.METHODS: Eleven male patients previously treated with omeprazole (n=7, mean dosage: 63 mg/day; range: 20-100 mg/day) or lansoprazole (n=4, mean dosage: 75 mg/day; range: 30-120 mg/day) were included. These patients underwent a 24-hour intragastric pH-metry, measurement of basal acid output and of serum gastrin first while receiving their usual therapy and second after 7 to 10 days of pantoprazole treatment at a mean dosage of 116 mg/day (range: 40-200 mg/day). Basal acid output was evaluated after each intragastric pH-metry, one hour before the next intake of proton pump inhibitor and a serum gastrin curve was determined according to 9 fixed time points.RESULTS: One patient dropped out before the second intragastric pH-metry due to an adverse event (varicella) unrelated to pantoprazole and was reinvestigated thereafter. The median 24-h intragastric pH with pantoprazole was not significantly different than that with the other proton pump inhibitors (5.3 versus 4.6, respectively; P=0.90). Neither the median basal acid output values nor the median serum gastrin levels were significantly different between pantoprazole and the other proton pump inhibitors.CONCLUSION: In these patients with the Zollinger-Ellison syndrome, pantoprazole was well tolerated and equally effective to the other proton pump inhibitors in terms of antisecretory potency.     

Effects of esomeprazole on acid output in patients with Zollinger-Ellison syndrome or idiopathic gastric acid hypersecretion

OBJECTIVES: To evaluate the efficacy and safety of oral esomeprazole in the control of gastric acid hypersecretion in patients with hypersecretory states. METHODS: In this 12-month, open-label, multicenter study, acid output (AO) was evaluated at baseline, day 10, and months 3, 6, and 12. The starting dose of esomeprazole was 40 mg or 80 mg twice daily. On day 10, patients with controlled AO were maintained on the same dose, while those with uncontrolled AO had their doses increased (maximum dose 240 mg/day) until control was attained. Esophagogastroduodenoscopy (EGD) was performed at baseline and at 6 and 12 months. Safety and tolerability were assessed throughout the study by EGD, gastric analysis, and adverse events. RESULTS: Twenty-one patients (19 with Zollinger-Ellison syndrome [ZES], 2 with idiopathic gastric acid hypersecretion [IGH]) completed the study. Of the 20 patients with controlled AO at day 10, 18 (90%) had sustained AO control for the rest of the study. At 12 months, AO was controlled in 14 of 16 patients receiving esomeprazole 40 mg twice daily, in all 4 patients receiving esomeprazole 80 mg twice daily, and in the 1 patient receiving esomeprazole 80 mg 3 times daily. At 6 and 12 months, no patient had endoscopic evidence of mucosal disease. Esomeprazole was well tolerated; 1 patient had a serious adverse event (hypomagnesemia) attributed to treatment that resolved with magnesium supplementation during continued treatment. CONCLUSION: Esomeprazole in appropriately titrated doses controls AO over 12 months in patients with hypersecretory states and is well tolerated.     

Salivary and gastric epidermal growth factor in patients with Zollinger-Ellison syndrome: its protective potential

OBJECTIVE: Evidence is accumulating that epidermal growth factor (EGF) is a major molecule contributing to the maintenance of the integrity of the upper alimentary tract mucosa before and after injury by acid and pepsin. Patients with Zollinger-Ellison Syndrome (ZES) typically have hypersecretion of acid and pepsin; however, the concentration and rate of secretion of salivary and gastric EGF that could counteract these potentially aggressive factors are unknown. Accordingly, this study was conducted to determine whether EGF affords mucosal protection in ZES patients. METHODS: The concentration and output of salivary (sEGF) and gastric epidermal growth factor (gEGF) were measured in eight patients with ZES and the results compared to those in 17 patients with nonulcer dyspepsia (NUD), serving as a control group. All patients had normal esophageal and gastric mucosa as determined by endoscopy. Total saliva was collected during 1-h parafilm- and 1-h pentagastrin/parafilm-stimulated conditions, as well as basal and pentagastrin-stimulated gastric juice. The concentration and output of EGF were determined by radioimmunoassay. RESULTS: The concentration of EGF in saliva collected from ZES patients after parafilm chewing was significantly higher compared to that in NUD patients (4.61 +/- 0.59 vs 2.75 +/- 0.50 ng/ml, p < 0.05). The concentration of EGF in saliva collected after pentagastrin stimulation in ZES patients was also significantly higher than in NUD patients (4.37 +/- 0.73 vs 2.22 +/- 0.37 ng/ml, p < 0.05). Salivary EGF output during parafilm chewing in ZES and NUD were similar (68 +/- 6.4 vs 109 +/- 25.2 ng/h). Salivary EGF output after administration of pentagastrin in ZES and NUD was also similar (66 +/- 6.1 vs 132 +/- 45.4 ng/h). Basal EGF output in the gastric juice of patients with ZES was 3-fold higher than in patients with NUD (801 +/- 73 vs 271 +/- 32 ng/h, p < 0.01). Pentagastrin-stimulated EGF output was similar in both groups (705 +/- 92 vs 675 +/- 168 ng/h). CONCLUSIONS: Patients with ZES have a significantly higher EGF concentration in saliva and EGF output in basal gastric juice. This elevated content of salivary and gastric EGF in ZES patients may play a protective role in preventing the development of reflux esophagitis and gastric ulcer under the impact of gastric acid and pepsin hypersecretion.     

Basophilic leukemia and the hypersecretion of gastric acid and pepsin

A 48-yr-old man with chronic myelogenous leukemia and basophilia developed a duodenal ulcer and hemorrhage. Gastric analysis revealed basal hyper-secretion of acid (33.1 mEq/h) and pepsin (44.5 x 10(-4) peptic units/h). Blood, serum, and urine histamine was elevated and serum gastrin was normal. Although acid output was markedly suppressed with ranitidine (50 mg i.v.), pepsin secretion was only inhibited 63% and had returned to basal levels by the sixth hour. Maximal acid output does not suggest a trophic effect of histamine in this patient. The previously reported cases of basophilic leukemia and gastric hypersecretion or duodenal ulcer disease are reviewed.     

Hypersecretory duodenal ulcer and Helicobacter pylori infection: a four-year follow-up study.

BACKGROUND: About 10% of duodenal ulcer patients are characterized by gastric acid hypersecretion with normal gastrin values. Relapsing duodenal ulcer after Helicobacter pylori cure has been related to high acid output and maintenance antisecretory therapy has been suggested in hypersecretory duodenal ulcer patients. The role of Helicobacter pylori infection and the effects of Helicobacter pylori cure in hypersecretory duodenal ulcer patients still remain to be fully studied. AIM: To study: a) whether gastric acid hypersecretion "per se" is a risk factor for duodenal ulcer recurrence; b) whether maintenance antisecretory therapy is necessary after eradication in hypersecretory duodenal ulcer patients. PATIENTS: The study population comprised 8 hypersecretory duodenal ulcer patients, selected from a population of 79 Helicobacter pylori-positive duodenal ulcer patients. METHODS: Hypersecretory duodenal ulcer patients were followed-up for at least 4 years after eradication. Gastric acid secretion was measured again 12 months after Helicobacter pylori eradication. Gastroscopy with histology was performed 3, 6, 12 and 36 months after treatment, 13C-urea breath test after 42 months; clinical questionnaires were completed every 6 months. RESULTS: After eradication, despite a not significantly reduced high acid output (median value of basal acid output and pentagastrin-stimulated acid output, respectively, 23.1 mEq/h and 64.1 mEq/h before treatment vs 16 mEq/h and 49.7 mEq/h 12 months after treatment), all patients were free from symptoms, none of them had duodenal ulcer relapse or complications (7/8 before treatment), or needed antisecretory maintenance therapy, except for one patient taking non-steroidal anti-inflammatory drugs. CONCLUSIONS: These findings, obtained in a selected population of hypersecretory duodenal ulcer patients with long-term follow-up, suggest that after successful Helicobacter pylori eradication gastric acid hypersecretion "per se" is not able to determine the recurrence of duodenal ulcer.     

Gastric acid hypersecretion in refractory gastroesophageal reflux disease

We prospectively evaluated gastric acid output (mEq/h), gastric volume output (ml/h), ambulatory 24-h esophageal pH monitoring, and the endoscopic appearance of the esophagus in 23 patients undergoing treatment of chronic long-standing pyrosis. Twelve of these 23 individuals (52%) remained symptomatic after 3 mo of standard antisecretory treatment with ranitidine, 150 mg twice daily. When compared with initial responders, those patients who did not experience complete symptomatic relief on therapy had significantly higher basal acid output (p less than 0.001), basal volume output (p less than 0.02), and basal upright (but not supine) reflux time (p less than 0.05). Nine of the 12 patients who did not respond to initial treatment had gastric acid hypersecretion (basal acid output greater than 10 mEq/h), and 10 of the 12 had Barrett's epithelium compared with only 1 patient in the initial-responder group (p less than 0.001). All 12 nonresponders were treated for an additional 3 mo with increased doses of ranitidine (mean, 1280 mg/day; range, 600-1800 mg/day), and complete disappearance of pyrosis occurred in 10 of the 12, although no significant endoscopic regression was observed in the extent of the underlying columnar mucosa in those with Barrett's esophagus over the 6-mo duration of the study. A significant correlation was shown between the daily ranitidine dose required to eliminate symptoms and the pretreatment basal acid output (r = 0.81, p less than 0.001); gastric acid output had to be almost totally suppressed (i.e., less than 1 mEq/h) for pyrosis to disappear completely. No side effects occurred with any of these high doses of ranitidine. We conclude that a subgroup of patients with long-standing symptomatic gastroesophageal reflux disease who do not respond to standard ulcer-healing doses of histamine2-receptor antagonists are hypersecretors of basal gastric acid and require increased acid-suppressive therapy. Many of these individuals also have underlying Barrett's epithelium.     

Gastrointestinal dysfunction in systemic mastocytosis. A prospective study

In 16 consecutive patients with systemic mastocytosis, we prospectively evaluated a variety of gastrointestinal functions and examined how they relate to the occurrence of gastrointestinal symptoms. Nine patients had either a duodenal ulcer or duodenitis. Hypersecretion of gastric acid was present in 6 patients, and in these patients the mean basal acid output was 20.7 +/- 4.1 mEq/h (range 14-39 mEq/h). Impaired small intestinal absorption occurred in 5 patients, although this was usually mild. The mean fractional emptying rate of liquids for all patients (14.7% +/- 2.3% per minute) did not differ from that for controls (10.7% +/- 0.6% per minute). Mean mouth-to-cecum transit time measured by breath hydrogen testing was the same among patients (87.7 +/- 6.7 min) and controls (86.7 +/- 8.0 min). Plasma histamine concentrations were increased in all patients (mean 1886 pg/ml, range 480-7450) and correlated with the basal acid output (r = 0.64, p less than 0.02) but not maximal acid output or the presence or absence of pain or diarrhea. Mean fasting plasma concentrations of motilin, substance P, and neurotensin from 6 patients did not differ significantly from controls, whereas gastrin and vasoactive intestinal peptide were significantly less than in controls (p less than 0.01). Gastrointestinal symptoms, consisting of abdominal pain or diarrhea, occurred in 80% of patients. Abdominal pain classified as dyspeptic was usually associated with acid-peptic disease of the duodenum and hypersecretion of gastric acid, whereas abdominal pain of a nondyspeptic character was not. Only in those cases of diarrhea consisting of greater than 200 g stool/day was gastric acid hypersecretion frequently found. Neither fecal urgency nor nondyspeptic pain could be accounted for by alterations of gastrointestinal transit. These results demonstrate that gastrointestinal symptoms, peptic disease, and mild malabsorption are much more common than described previously in patients with systemic mastocytosis. Furthermore, the results provide no evidence for the contention that altered gastrointestinal transit is involved in the pathogenesis of these symptoms.     

Sleep patterns and gastric acid secretion in duodenal ucler disease.

Five normal volunteers and five patients with duodenal ulcer (DU) disease were studied for five consecutive nights. All subjects underwent placement of a nasogastric tube, continuous collection of gastric juice, and continuous electroencephalographic monitoring of sleep. Gastric juice was collected in 20-minute samples by remote suction (Gomco). Blood samples were drawn every 20 minutes on the third night via an indwelling venous needle. Results showed no significant correlations between the sleep variables and the gastric acid secretion measures or between the sleep variables and serum gastrin levels. Acid secretion decreased from hour 1 to hour 2 in controls and in patients with inactive DU disease, while it increased in patients with active DU disease. Each subject had at least one night of recording in which continuous gastric secretion was less than 0.1 mEq per 20-minute sample. It appears unlikely that the gastric discomfort of DU patients can be attributed to acid hypersecretion triggered by rapid eye movement sleep.     

Histopathology of the gastric oxyntic mucosa in two different patient groups during long-term treatment with omeprazole

OBJECTIVES: Hypochlorhydria, hypergastrinaemia, inflammation and Helicobacter pylori infection, dose and duration of omeprazole treatment may separately, or in combination, influence the proliferation of enterochromaffin-like (ECL) cells and parietal cell changes in gastric mucosa. To assess the effects of these variables comparisons were carried out in patients with the acid related Zollinger-Ellison syndrome (ZES) versus patients with progressive systemic sclerosis (PSS) and gastro-oesophageal reflux disease. METHODS: Twenty-five patients with PSS and 16 patients with ZES were included and received continuous omeprazole treatment for a mean of 7.5 and 9 years. The patients were investigated every 6-12 months with endoscopy, biopsies and histology, and plasma gastrin measurements. PSS patients were titrated by 24 h pH-metry to oesophageal pH>4, and all ZES patients were titrated to a basal acid output of zero H+. RESULTS: Changes towards diffuse and linear ECL cell hyperplasia were observed in 41% of the PSS patients. Micronodular hyperplasia and neoplasia were not seen. In the ZES patients changes towards linear and micronodular hyperplasia were observed in all patients. Two patients developed ECL cell carcinoids; one of these had MEN-1 syndrome. Also parietal cell changes were more pronounced in the ZES group than in the PSS group. CONCLUSIONS: In patients without intrinsic acid hypersecretion and hypergastrinaemia significant proliferation of ECL cells is not an issue irrespective of gastric mucosal inflammation, omeprazole dose, duration of treatment and acid inhibition. The level of gastrin secretion and high plasma gastrin appear to accelerate ECL cell proliferation and parietal cell changes possibly influenced by chronic gastritis and H. pylori infection.     

Parenteral antisecretory drug therapy in patients with Zollinger-Ellison syndrome

Forty-six patients with Zollinger-Ellison syndrome were studied prospectively to determine a safe and effective method and criterion for controlling gastric acid hypersecretion during periods when oral antisecretory agents could not be used. In each patient it was possible to reduce acid secretion to less than or equal to 10 mEq/h after an i.v. bolus of 150 or 300 mg of cimetidine and a stepwise titration of cimetidine given by continuous infusion. The mean dose given by i.v. infusion was 2.9 mg/kg body wt.h but there was a wide range (0.5-7.0 mg/kg body wt.h) and the minimal dose had to be determined individually for each patient. The minimal i.v. cimetidine dose did not correlate with basal or maximal acid output or fasting gastrin concentration, but correlated closely with either the previous oral dose of cimetidine (r = 0.96, p less than 0.001) or the previous oral dose of ranitidine or famotidine (r = 0.95, p less than 0.001). To study the efficacy and safety of an i.v. infusion of cimetidine, 34 patients undergoing surgery were maintained on i.v. cimetidine for a mean of 12 days (range 1-83 days). One-half of the patients did not require dose adjustment, whereas the remainder required an average of 2 adjustments, usually in the first 3 postoperative days. No patient developed complications attributable to gastric acid hypersecretion in the postoperative period, and there was no detectable neurologic, hematologic, or hepatic toxicity. This study demonstrates that a continuous i.v. infusion of cimetidine adequately inhibits gastric acid hypersecretion in patients with Zollinger-Ellison syndrome. However, high doses were frequently required, the dose had to be determined in a stepwise fashion individually for each patient, and the i.v. dose correlated with the previous oral dose. Reducing acid secretion to less than or equal to 10 mEq/h was a safe criterion during surgery and continuous i.v. cimetidine was safe and effective in achieving this degree of control for up to 83 days.     

Long-term efficacy and safety of omeprazole in patients with Zollinger-Ellison syndrome: a prospective study

To determine the long-term efficacy, safety, and toxicity of omeprazole, we studied 40 patients with Zollinger-Ellison syndrome given omeprazole for 6-51 mo (median 29). The mean daily dose of omeprazole required to control gastric acid secretion was 82 +/- 31 mg. Thirty-one patients required omeprazole once per day. In 9 patients acid output was not controlled by 120 mg once per day, but was controlled by 60 mg every 12 h. The daily dose of omeprazole correlated with the previous dose of histamine H2-receptor antagonist (r = 0.89, p less than 0.001), basal acid output (r = 0.43, p less than 0.01), and maximal acid output (r = 0.39, p less than 0.02) but not with serum concentration of gastrin (r = -0.32). Increases in the dose of omeprazole were required in 9 patients. Twenty-nine patients had mild peptic symptoms with acid outputs less than 10 mEq/h while taking histamine H2-receptor antagonists. Symptoms resolved completely in 23 patients and partially in 3 when taking omeprazole. Omeprazole prevented mucosal disease in all patients including 17 in whom histamine H2-receptor antagonists had produced only partial resolution despite acid output being less than 10 mEq/h and in those with symptoms during omeprazole therapy. Omeprazole therapy was not associated with any significant side effects, nor with any evidence of hematologic or biochemical toxicity. Serum concentrations of gastrin did not change significantly during therapy. In 6 patients treated with omeprazole for 1 yr there was no change in basal or maximal acid output. In all patients, gastric morphology and histopathology demonstrated no evidence of gastric carcinoid formation. These results demonstrate that with long-term treatment of up to 4 yr, omeprazole is safe, with no evidence of hematologic, biochemical, or gastric toxicity. Furthermore, omeprazole remained effective, with only 23% of patients requiring an increase in dose, and continued to control symptoms in patients who had not been entirely symptom-free despite high doses of histamine H2-receptor antagonists. Omeprazole is now the drug of choice in patients with Zollinger-Ellison syndrome.     

Intravenous Pantoprazole as Initial Treatment in Patients With Gastroesophageal Reflux Disease and a History of Erosive Esophagitis: A Randomized Clinical Trial

We sought to evaluate safety and efficacy of IV pantoprazole when used as initial therapy in patients with gastroesophageal reflux disease (GERD) and a history of erosive esophagitis (EE) in a double-blind, placebo-controlled, randomized, parallel-group study. Patients were randomized to 7 days of once-daily IV or oral pantoprazole (40 mg) or placebo. Efficacy variables included maximal acid output, basal acid output, and changes from baseline in frequency/severity of GERD symptoms, and frequency of antacid usage. Seventy-eight patients were randomized (n=26/27/25 [IV/oral/placebo]). Mean maximal acid output was 8.4, 6.3, and 20.9 mEq/h for IV or oral pantoprazole, and placebo, respectively. For pantoprazole versus placebo, maximal and basal acid output were significantly lower (P<.001) and there was a numerical trend toward improved GERD and antacid usage. Both treatments were well tolerated. In conclusion, IV/oral pantoprazole were similarly effective in suppressing basal and pentagastrin-stimulated gastric acid secretion in GERD patients with a history of EE.