Gastric Acid Hypersecretion Research Articles

Long-term Outcome of Helicobacter pylori–Negative Idiopathic Bleeding Ulcers: A Prospective Cohort Study

Helicobacter pylori-negative idiopathic ulcers are increasingly recognized. The secular trend and long-term outcome of this condition are unknown. We prospectively studied consecutive patients with bleeding gastroduodenal ulcers from January to December 2000. The incidence and etiology of ulcers during this period were compared with that between September 1997 and August 1998. H. pylori-negative idiopathic ulcers were defined as negative tests for H. pylori, no exposure to analgesics within 4 weeks, and absence of other risk factors for ulcers. After the ulcers had healed, patients with H. pylori-negative idiopathic ulcers and patients with H. pylori ulcers who received eradication therapy were followed up for 12 months without anti-ulcer drugs. Six hundred thirty-eight patients had bleeding ulcers: 213 (33.4%) were H. pylori ulcers, and 120 (18.8%) were H. pylori-negative idiopathic ulcers (vs 480 [50.3%] H. pylori ulcers and 40 [4.2%] H. pylori-negative idiopathic ulcers in 1997-1998; P < .001). H. pylori-negative idiopathic ulcers accounted for 16.1% of patients who were admitted for bleeding and 42.4% of patients who bled while in the hospital (P < .0001); 28.3% of patients with H. pylori-negative idiopathic ulcers had histologic evidence of past H. pylori infection. The probability of recurrent ulcer complications in 12 months was 13.4% (95% CI: 7.3%-19.5%) in patients with H. pylori-negative idiopathic ulcers and 2.5% (95% CI: 0.4%-4.6%) in patients with H. pylori ulcers who received eradication therapy (P = .0002). The incidence of H. pylori-negative idiopathic bleeding ulcers is rising. These ulcers are prone to recurrent complications.

A Follow-up Study of Patients With Zollinger-Ellison Syndrome in the Period 1966-2002

To evaluate the clinical history of a series of patients with Zollinger-Ellison syndrome (ZES) in the period 1966 to 2002, before and after the introduction of the current antisecretive H2 receptor antagonists and proton pump inhibitors into clinical practice. The study involved 18 ZES patients (9 males; mean age, 43 years; range, 12-70 years), 8 with Type 1 multiple endocrine neoplasia (MEN-1), diagnosed on the basis of standard criteria. We considered the type, number and effectiveness of surgical interventions before and after appropriate treatment, the localization of the gastrinoma, the presence of associated diseases, the causes of death, and the duration of survival. Total gastrectomy (but not antrectomy and vagotomy) and full compliance to antisecretory treatment reduced the number of operations from 29 to 9. One patient was cured (5.5%), whereas relapsing gastrinomas occurred in 4 patients and associated diseases or complications in ten. Death was related to ZES in 5 patients and to other causes in 4. Curing gastrinoma or appropriately inhibiting gastric acid hypersecretion in ZES patients prevent death and favors long-term survival, regardless of gastrin levels and the size or number of tumors.

Idiopathic gastric acid hypersecretion presenting as a diarrheal disorder and mimicking both Zollinger???Ellison syndrome and Crohn??s disease

Many gastric acid hypersecretory states (basal acid output of greater than 15.0 mEq/h) exist for which the etiology is known, such as Zollinger-Ellison syndrome, systemic mastocytosis, antral exclusion, antral predominant Helicobacter pylori gastritis (antral G cell hyperplasia), chronic gastric outlet obstruction, short gut syndrome and basophilic leukemias. However, many hypersecretory patients have no identified etiology for their acid hypersecretion and are designated as idiopathic gastric acid hypersecretors with a basal acid output of greater than 10 mEq/h and a normal serum gastrin level. Because of the gastric acid hypersecretion these patients also commonly have an increased frequency of stools. Idiopathic gastric acid hypersecretion represents a known cause of gastric acid hypersecretion that is far more common than Zollinger-Ellison syndrome and it has a markedly different treatment regimen and natural history. We report a case of a patient with idiopathic gastric acid hypersecretion previously misdiagnosed as having Crohn's disease because of a presenting complaint of diarrhea and mimicking Zollinger-Ellison syndrome because her fasting serum gastrin level was elevated when incorrectly measured in the presence of antisecretory treatment.

Definitions and classification of dyspepsia: pH, Helicobacter pylori, non‐steroidal anti‐inflammatory drugs – should we include gastro‐oesophageal reflux disease?

The aetiology of dyspepsia (defined as pain/discomfort inthe upper abdomen) may be organic or functional.Organic causes include luminal gastrointestinal tractdisorders, medication use, pancreatobiliary disease andsystemic disorders. Functional dyspepsia may be due toheightened visceral sensitivity, abnormal gastroduode-nal motility, gastric acid hypersecretion, Helicobacterpylori-associated gastritis or psychosocial factors. Inves-tigation of the pathogenesis of dyspepsia may revealpeptic ulcer disease, gastro-oesophageal reflux or malig-nancy. In the absence of structural or biochemicalcauses, the cause of the symptoms is related tofunctional dyspepsia.

Zollinger–Ellison Phenotype in the Absence of Hypergastrinemia and Islet-Cell Tumor

Patients with the Zollinger-Ellison syndrome are characterized by islet-cell tumors, striking gastric acid hypersecretion, and peptic ulcer disease. They often experience severe abdominal pain, diarrhea, and gastrointestinal bleeding with potentially life-threatening consequences. It is a rare syndrome caused by non-beta cell islet-cell tumors (gastrinomas) located in or in proximity to the pancreas. These tumors freely secrete gastrin, a peptide hormone that serves as a powerful stimulant of gastric acid secretion. Exuberant secretion of gastrin from the gastrinomas produces severe gastric acid hypersecretion that often leads to impressive peptic ulcer disease and the constellation of symptoms listed above. We describe a patient presenting with clinical manifestations characteristic of the ZES with strikingly elevated gastric acid secretion,multiple ulcers in the first and second portions of the duodenum and diarrhea, but in absence of islet-cell tumor and/or hypergastrinemia.

Clinical outcome using lansoprazole in acid hypersecretors with and without Zollinger-Ellison syndrome: A 13-year prospective study

Unremitting gastric acid and pepsin hypersecretion causes serious persistent and relapsing lesions, but the natural history with medical treatment alone has not been well-defined. The aims of this study were to heal and prevent relapse of acid/peptic lesions during acid suppression and to analyze benefits and risks during long-term lansoprazole treatment. Sixty-seven patients (49 with Zollinger-Ellison syndrome [ZES], 18 without), with basal acid output (BAO) >15 mmol/h or >5 mmol/h if post-antrectomy (n = 9, all ZES), were treated with individually optimized doses of lansoprazole (7.5-450 mg/day; median, 75 mg/day) to reduce BAO to <5 mmol/h or <1 mmol/h post-antrectomy and underwent endoscopy every 3-6 months for up to 13 years (median, 6.25 years). Before treatment, 94% had duodenal ulcer, 64% had esophagitis, 60% had 1 or more bleeding episodes, 13% had perforated ulcers, 90% had pain, 60% had heartburn, and 40%-48% had diarrhea, vomiting, and/or weight loss. Forty-seven patients (70%) remained symptom- and lesion-free, whereas 13 (20%) had mild, transient relapses, and 7 (10%) had more complicated relapses. Overall, symptoms were reduced 90+%; ulcer or esophagitis relapsed in 4.8% of patients/year, unrelated to Helicobacter pylori , whereas complications declined to <2%/y. Post-antrectomy ZES patients had 3.6-fold higher relapse rates than unoperated ZES patients (67% vs 18%, respectively). With BAO >5 mmol/h in intact patients, relative risk of relapse was 4.1, confidence interval 2.1-8.1, P < .001. Twenty patients died, 3 as a result of ZES (2 metastatic gastrinomas). With individually optimized medical suppression of acid secretion, 90% of patients had good to excellent long-term outcomes without surgery, with an annualized total relapse rate of <5%.

Zollinger-Ellison syndrome revisited: Diagnosis, biologic markers, associated inherited disorders, and acid hypersecretion

Despite general awareness of Zollinger-Ellison syndrome (ZES) by most physicians and more than 3000 articles written about it since 1955, the diagnosis of ZES is still delayed for a mean of 5 years. Recent studies show it is being delayed even more with the widespread use of proton pump inhibitors. A number of tumor markers, in addition to assessing serum gastrin, such as chromogranin A, neuron-specific enolase, and subunits of chorionic gonadotropin, have been proposed for use in either the diagnosis of pancreatic endocrine tumors, such as gastrinomas, or for assessment of tumor extent and growth. In this article important recent insights into the diagnosis of ZES as well as the clinical usefulness of assessing tumor markers for diagnosis and determination of disease extent and growth are discussed. Approximately 25% of ZES cases are due to multiple endocrine neoplasia type 1 (MEN1). A number of important studies in this group of patients are also reviewed. Finally, almost every patient with ZES has marked gastric acid hypersecretion, and its current treatment as well as the long-term possible side effects are reviewed briefly.

ZOLLINGER-ELLISON SYNDROME WITH NORMAL SERUM GASTRIN LEVEL

Introduction: Zollinger-Ellison syndrome is characterized by gastric acid hypersecretion leading to refractory/recurrent peptic ulceration due to non-beta islet cell tumor. Diagnosis of Zollinger-Ellison syndrome is made by elevated serum gastrin levels or secretin stimulation test in appropriate clinical setting. We describe a case of Zollinger-Ellison that had near normal serum gastrin levels. Diagnosis was made with endoscopic ultrasound and confirmed by octreotide receptor scintigraphy and histopathology. Case Report: 53-year-old white male with history of 40 lbs weight loss over four months and peptic stricture was referred for evaluation of abdominal pain, diarrhea and symptoms of gastroesophageal reflux despite being on omeprazole 40 mg twice daily. Abdominal exam did not show any evidence of fluid or masses. The patient underwent an esophageal gastroduodenoscopy, which showed diffuse ulceration of esophagus, erosions in the stomach, ulceration in the duodenal bulb and second part of the duodenum. Liver enzymes were elevated and a trans abdominal ultrasound showed dilated pancreatic duct. A CT scan obtained at the same time did not reveal any abnormalities. Serum gastrin level initially was 37 pg/ml and later rose to 161 pg/ml; normal (40–200 pg/ml). Patient refused secretin stimulation test because of fear of symptoms off proton pump inhibitors. An endoscopic ultrasound (EUS) was performed which showed a 25 mm × 30 mm mass in the head of the pancreas. Fine needle aspirate of that mass suggested endocrine tumor. Octerotide scan showed high uptake in the mid epigastric area consistent with gastrinoma. The patient underwent a Whipple procedure and resection of low grade neuroendocrine tumor of the pancreas which stained positive for chromogranin, synaptophysin and pancytokeratin consistent with gastrinoma. The patient was discharged home after one week stay in the hospital. Currently patient is doing well without any complaints of gastroesophageal reflux, one-month post surgery. Discussion: Our case illustrates the fact that normal serum gastrin levels do not rule out the diagnosis of Zollinger-Ellison syndrome. When clinical suspicion of Zollinger- Ellison syndrome is high additional testing i.e. secretin stimulation test (which shows a paradoxical rise in the gastrin levels) or EUS should be done to confirm or refute the diagnosis. A EUS can be very helpful in such situations by not only establishing the diagnosis but also localizing the tumor for surgery.

Images of interest. Gastrointestinal: multiple endocrine neoplasia type I and duodenal gastrinomas.

Multiple endocrine neoplasia type I (MEN I) syndrome is an autosomal dominant disorder characterized by tumors in the pituitary gland, parathyroid glands and upper gastrointestinal tract. While almost all patients have pituitary and parathyroid tumors, only approximately 60% develop islet cells tumors that secrete gastrin (gastrinomas). The presence of gastrinomas causes the Zollinger–Ellison syndrome, a syndrome characterized by hypersecretion of gastric acid and aggressive peptic ulceration. However, only a minority of patients with the Zollinger–Ellison syndrome have MEN I; the majority (70%) have ‘sporadic’ tumors without MEN I. Most gastrinomas occur in the ‘gastrinoma triangle’ that includes the first, second and third parts of the duodenum and the head of the pancreas. However, tumors can occur elsewhere in the pancreas, in peripancreatic lymph nodes and, rarely, in distant sites such as the ovary. Whether tumors in peripancreatic lymph nodes are primary tumors or a site of local spread from a tiny focus in the pancreas remains unclear. Typical gastrinomas occur with similar frequency in the duodenum and pancreas. However, in contrast to ‘sporadic’ gastrinomas, gastrinomas associated with MEN I are more likely to be located in the duodenum, more likely to be small and multiple and more likely to be associated with gastric carcinoid tumors. In addition, gastrinomas associated with MEN I have a lower metastatic potential and a greater longer-term survival (90% at 20 years). Because of the multifocal nature of gastrinomas in MEN I, cure by surgery is less frequent and the majority of patients are managed medically with proton pump inhibitor drugs. Figures 1 and 2 show the endoscopic appearances of multiple polypoid gastrinomas in a patient with MEN I. The diagnosis was confirmed by endoscopic biopsies.

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

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. 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). 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). 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.

Effect of Helicobacter pylori infection on gastric acid secretion and meal-stimulated serum gastrin in children.

Comparative studies of gastric acid secretion in children related to Helicobacter pylori infection are lacking. The purpose of this study was to compare acid secretion and meal-stimulated gastrin in relation to H. pylori infection among pediatric patients. Thirty-six children aged 10-17 years (17 with H. pylori infection) undergoing diagnostic endoscopy participated in the study. Diagnoses included gastritis only (n = 23), duodenal ulcer (n = 5) and normal histology (n = 8). Gastric acid output was studied using the endoscopic gastric secretion test before and 2-3 months after H. pylori eradication. Meal-stimulated serum gastrin response was assessed before and 12 months after eradication. H. pylori gastritis was typically antrum-predominant. Acid secretion was greater in H. pylori-positive patients with duodenal ulcer than in gastritis-only patients or controls [mean +/- standard error (SE): 6.56 +/- 1.4, 3.11 +/- 0.4 and 2.65 +/- 0.2 mEq/10 minutes, respectively; p <.001]. Stimulated acid secretion was higher in H. pylori-positive boys than girls (5.0 +/- 0.8 vs. 2.51 +/- 0.4 mEq/10 minutes, respectively; p <.05). Stimulated acid secretion pre- and post-H. pylori eradication was similar (5.47 +/- 0.8 vs. 4.67 +/- 0.9 mEq/10 minutes, respectively; p =.21). Increased basal and meal-stimulated gastrin release reversed following H. pylori eradication (e.g. basal from 134 to 46 pg/ml, p <.001 and peak from 544 to 133 pg/ml, p <.05). H. pylori infection in children is associated with a marked but reversible increase in meal-stimulated serum gastrin release. Gastric acid hypersecretion in duodenal ulcer remains after H. pylori eradication, suggesting that the host factor plays a critical role in outcome of the infection.

Current surgical management of Zollinger-Ellison syndrome (ZES) in patients without multiple endocrine neoplasia-type 1 (MEN1).

The role of surgery in the management of patients with sporadic (not part of multiple endocrine neoplasia type 1) Zollinger-Ellison syndrome (ZES) is controversial. In this setting, 60-90% of gastrinomas are malignant and medical therapy can control the gastric acid hypersecretion in virtually every patient. Therefore, the progression of tumor is the major determinant of survival. Surgery will cure approximately one-third of patients with sporadic ZES. It will decrease the development of liver metastases and may improve survival. Somatostatin receptor scintigraphy is the best preoperative localization study. Its results are as good as all other imaging studies combined. Operative techniques should always include duodenotomy (opening the duodenum) and meticulous dissection of lymph nodes in the gastrinoma triangle, because duodenal primary tumors are often missed and lymph node primary tumors or metastases are common. Postoperative evaluation should include secretin test because it is the most sensitive method to document cure and detect tumor recurrence.

Zollinger-Ellison Syndrome.

Zollinger-Ellison syndrome (ZES) is caused by a gastrin-producing tumor called a gastrinoma, which results in gastric acid hypersecretion. Gastrin stimulates the parietal cell to secrete acid directly and indirectly by releasing histamine from enterochromaffin-like (ECL) cells, and induces hyperplasia of parietal and ECL cells. ZES should be suspected in patients with severe erosive or ulcerative esophagitis, multiple peptic ulcers, peptic ulcers in unusual locations, refractory peptic ulcers, complicated peptic ulcers, peptic ulcers associated with diarrhea, and a family history of multiple endocrine neoplasia type 1 (MEN-1) or any of the endocrinopathies associated with MEN-1. The initial diagnostic test for ZES should be a fasting serum gastrin level when antisecretory medications are discontinued. If the gastrin level is elevated, gastric acidity should be assessed through pH or gastric analysis. It should be noted that hypochlorhydria causes feedback stimulation of antral gastrin secretion. In suspected cases of ZES with mild hypergastrinemia, the secretin stimulation test may be useful. Initial treatment for ZES should be oral high-dose proton pump inhibitors. If parenteral therapy is needed, intermittent bolus injection of pantoprazole is recommended. Total gastrectomy and antisecretory surgery is rarely required. Somatostatin receptor scintigraphy (SRS) is the initial localization study of choice. Endoscopic ultrasound (EUS) may have a similar sensitivity for identifying primary tumors. A combination of SRS and EUS detects greater than 90% of gastrinomas. In patients without metastasis and without MEN-1, surgical cure is possible in 30%. It has been suggested that patients with gastrinomas larger than 2.5 cm, irrespective of whether they have MEN-1, should undergo surgical resection in an effort to decrease the risk for metastasis.

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.

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

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. 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). 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. 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.

Optimal treatment of Zollinger-Ellison syndrome and related conditions in elderly patients.

Zollinger-Ellison syndrome is characterised by refractory peptic ulcer disease, severe diarrhoea and gastric acid hypersecretion associated with an islet-cell tumour of the pancreas (gastrinoma). The true incidence and prevalence of this rare disease is unknown; in the US, the frequency is one per one million people and the age at presentation varies from 7 to 90 years. Zollinger-Ellison syndrome is sporadic in 62-80% of cases and in 20-38% of cases is associated with multiple endocrine neoplasia type 1 (MEN 1). The diagnosis of Zollinger-Ellison syndrome is certain when the plasma gastrin is >1000 pg/mL and the basal acid output is >15 mEq/h in patients with an intact stomach, >5 mEq/h in gastrectomised patients, or when this hypergastrinemia is associated with a pH <2. The treatment is based on control of gastric acid hypersecretion and of the malignant tumour and its possible metastases. Proton pump inhibitors are the most effective antisecretory drugs and can be administered in the elderly at high dosages without drug-related adverse effects. As an initial therapy, daily dosages of omeprazole 80-100 mg or pantoprazole 40-160 mg are employed. In long-term treatment the doses can be greatly reduced once effective control of the gastric output has been established. Intravenous proton pump inhibitors may be administered when patients cannot take oral therapy, particularly in acute conditions. All sporadic localised gastrinomas should be excised if possible. When liver metastases are also present, their debulking may improve symptoms and survival, and facilitate medical treatment. There is some controversy as to the surgical approach for gastrinomas associated with MEN 1. Somatostatin analogues can be useful in reducing gastric acid hypersecretion, serum gastrin and gastric enterochromaffin-like (ECL) cells and can thus contribute to treating the disease more effectively. Their antiproliferative effect can be used in treating liver metastases. Chemotherapy is not the therapy of choice in patients with gastrinomas and is indicated only in those with malignant progressive disease; interferon alpha, embolisation and chemoembolisation are not advisable for the elderly. The treatment of elderly Zollinger-Ellison syndrome patients, similarly to all elderly oncological patients, should be based on the use of comprehensive geriatric assessment. This will enable the clinician to define the functional status of the elderly person, to decide whether the patient can tolerate surgery and/or the stress of antineoplastic therapy, and finally, to determine whether this patient can tolerate an aggressive treatment for Zollinger-Ellison syndrome or whether the only possible choice is palliative relief of symptoms.

Nutritional support in short bowel syndrome

Short bowel syndrome most commonly result after bowel resection for necrosis of the bowel. It may be caused by arterial or venous thrombosis, volvolus and in children, necrotizing enterocolitis. The other causes are Crohn's disease, intestinal atresia. The factors influencing the risk on short bowel syndrome are the remaining length of the small bowel, the age of onset, the length of the colon, the presence or absence of the ileo-coecal valve and the time after resection. Besides nutritional deficiencies there some other consequences of extensive resections of the small intestine (gastric acid hypersecretion, d-lactic acidosis, nephrolithiasis, cholelithiasis), which must be diagnosed, treated, and if possible, prevented. With current therapy, most patients with short bowel have normal body mass index and good quality of life.

Research agenda for pediatric gastroenterology, hepatology and nutrition: acid-peptic diseases. Report of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition for the Children's Digestive Health and Nutrition Foundation.

Research agenda for pediatric gastroenterology, hepatology and nutrition: acid-peptic diseases. Report of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition for the Children's Digestive Health and Nutrition Foundation.

Nutritional management of short bowel syndrome in adults.

Short bowel syndrome (SBS) comprises the sequelae of nutrient, fluid, and weight loss that occurs subsequent to greatly reduced functional surface area of the small intestine. Signs and symptoms of SBS include electrolyte disturbances; deficiencies of calcium, magnesium, zinc, iron, vitamin B12, or fat-soluble vitamin deficiency; malabsorption of carbohydrates, lactose, and protein; metabolic acidosis, gastric acid hypersecretion; formation of cholesterol biliary calculi and renal oxalate calculi; and dehydration, steatorrhea, diarrhea, and weight loss. Thorough nutritional management is the key factor in achieving an optimal outcome in SBS. Total parenteral nutrition is necessary in the early stages, as is replacement of excess fluid and electrolyte losses. Nutritional management of SBS has traditionally been divided into three phases: an acute phase when total parenteral nutrition is usually begun, an adaptation phase, and a maintenance phase. Recommendations regarding the need for parenteral nutrition vary depending on the presence or absence of certain factors: the ileocecal valve, jejunum, and functional colon. Patients with residual small bowel length of 100 cm or less usually require the administration of parenteral nutrition at home with good results. The total parenteral nutrition diet should consist of a majority of calories from fat, followed by protein, and the remaining as carbohydrates. Vitamins, minerals, and trace elements should also be added accordingly. Although total parenteral nutrition is initially necessary, treatment goals should focus on early transition to enteral nutrition followed by oral feeds. Other recent advances in the medical management of SBS include pharmacologic treatment and the use of specific nutrients and growth factors to stimulate intestinal absorption and adaptation. Both animal studies and clinical trials in humans have shown much promise in supplementation with growth factors and hormones. This strategy is likely to play a greater role in the treatment of SBS in the future.

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

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. 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). 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. 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.