Peptic ulcer pathophysiology

Non-steroidal Anti-inflammatory Drug (NSAID)-, Potassium Supplement-, Bisphosphonate-, and Doxycycline-Mediated Peptic Ulcer Effects: A Narrative Review

Peptic ulcers are a common condition that arises from an imbalance between acid production and gastroduodenal protective factors. Various drugs, including non-steroidal anti-inflammatory drugs (NSAIDs), potassium supplements, bisphosphonates, and doxycycline, can increase the development of peptic ulcers. NSAIDs are one of the most common medications prescribed for pain relief, and they also inhibit the formation of cyclooxygenase-1 (COX-1). COX-1 helps in the production of mucus that lines the stomach, so by inhibiting COX-1, NSAIDs reduce the mucus produced by the stomach and increase the likelihood of gastric ulcer formation. Additionally, NSAIDs are acidic, and increasing the amount of any acid in the stomach can result in promoting ulcer development. Potassium supplements are used to reduce the effects of hypertension, decrease the development of kidney stones, and treat hypokalemia. The various types of transporters and channels used to move potassium across cell membranes increase hydrogen being pumped, increasing gastric acid production and ulcer formation. Bisphosphonates are used to treat a variety of skeletal disorders that require inhibition of osteoclast activity. Nitric oxide (NO) has been shown to have a therapeutic effect on gastric ulcers, and some bisphosphonates have been shown to decrease the production of nitric oxide, resulting in increased damage to the gastric mucosa. Finally, doxycycline is a broad-spectrum tetracycline antibiotic that is typically used to treat anthrax poisoning, skin lesions, and sexually transmitted diseases. A harmful adverse effect of doxycycline is the formation of peptic and gastric ulcers related to the drug being highly acidic once it has dissolved.

Risk Factors for Mortality in Emergently Admitted Patients with Acute Gastric Ulcer: An Analysis of 15,538 Patients in National Inpatient Sample, 2005-2014

Background: Patients admitted emergently with a primary diagnosis of acute gastric ulcer have significant complications including morbidity and mortality. The objective of this study was to assess the risk factors of mortality including the role of surgery in gastric ulcers. Methods: Adult (18−64-year-old) and elderly (≥65-year-old) patients admitted emergently with hemorrhagic and/or perforated gastric ulcers, were analyzed using the National Inpatient Sample database, 2005−2014. Demographics, various clinical data, and associated comorbidities were collected. A stratified analysis was combined with a multivariable logistic regression model to assess predictors of mortality. Results: Our study analyzed a total of 15,538 patients, split independently into two age groups: 6338 adult patients and 9200 elderly patients. The mean age (SD) was 50.42 (10.65) in adult males vs. 51.10 (10.35) in adult females (p < 0.05). The mean age (SD) was 76.72 (7.50) in elderly males vs. 79.03 (7.80) in elderly females (p < 0.001). The percentage of total deceased adults was 1.9% and the percentage of total deceased elderly was 3.7%, a difference by a factor of 1.94. Out of 3283 adult patients who underwent surgery, 32.1% had perforated non-hemorrhagic ulcers vs. 1.8% in the non-surgical counterparts (p < 0.001). In the 4181 elderly surgical patients, 18.1% had perforated non-hemorrhagic ulcers vs. 1.2% in the non-surgical counterparts (p < 0.001). In adult patients managed surgically, 2.6% were deceased, while in elderly patients managed surgically, 5.5% were deceased. The mortality of non-surgical counterparts in both age groups were lower (p < 0.001). The multivariable logistic regression model for adult patients electing surgery found delayed surgery, frailty, and the presence of perforations to be the main risk factors for mortality. In the regression model for elderly surgical patients, delayed surgery, frailty, presence of perforations, the male sex, and age were the main risk factors for mortality. In contrast, the regression model for adult patients with no surgery found hospital length of stay to be the main risk factor for mortality, whereas invasive diagnostic procedures were protective. In elderly non-surgical patients, hospital length of stay, presence of perforations, age, and frailty were the main risk factors for mortality, while invasive diagnostic procedures were protective. The following comorbidities were associated with gastric ulcers: alcohol abuse, deficiency anemias, chronic blood loss, chronic heart failure, chronic pulmonary disease, hypertension, fluid/electrolyte disorders, uncomplicated diabetes, and renal failure. Conclusions: The odds of mortality in emergently admitted geriatric patients with acute gastric ulcer was two times that in adult patients. Surgery was a protective factor for patients admitted emergently with gastric perforated non-hemorrhagic ulcers.

Genetic liability to obesity and peptic ulcer disease: a Mendelian randomization study

BACKGROUND

Epidemiological evidence relating obesity to peptic ulcer disease (PUD) has been mixed. Here we sought to determine the causality in the association of obesity with PUD risk using the Mendelian randomization (MR) approach.

METHODS

This study was based on summary-level data for body mass index (BMI), waist-to-hip ratio (WHR), and PUD derived from large genome-wide association studies (GWASs). Single nucleotide polymorphisms significantly associated with BMI and WHR (P < 5 × 10^-8) were leveraged as instrumental variables. Causal estimates were pooled using several meta-analysis methods. In addition, multivariable MR was employed to account for covariation between BMI and WHR, as well as to explore potential mediators.

RESULTS

Genetically predicted higher BMI has a causal effect on PUD, with an OR of 1.34 per SD increase in BMI (~ 4.8 kg/m²) (P = 9.72 × 10^-16). Likewise, there was a 35% higher risk of PUD (P = 2.35 × 10^-10) for each SD increase in WHR (0.09 ratio). Complementary analyses returned consistent results. Multivariable MR demonstrated that adjustment for WHR largely attenuated the BMI-PUD association. However, the causal association of WHR with PUD risk survived adjustment for BMI. Both the associations remained robust upon adjustment for several traditional risk factors. Replication analyses using different instrumental variants further strengthened the causal inference. Besides, we found no evidence for the causal association in the reverse analyses from PUD to BMI/WHR.

CONCLUSIONS

This MR study revealed that obesity (notably abdominal obesity) is causally associated with higher PUD risk. Programs aimed at weight loss may represent therapeutic opportunities for PUD.

Gastrointestinal comorbidities in patients with psoriatic arthritis

Comorbidities associated with psoriatic arthritis (PsA) include cardiovascular diseases, diabetes mellitus, and obesity. This study evaluated the association between PsA and common gastrointestinal (GI) diseases. A retrospective study was performed in Israel's largest health care provider database between 2002 and 2013. 3161 PsA patients were matched for age and sex with 31610 randomly selected patients. We searched these patients' records for the presence of peptic ulcer disease (PUD), reflux esophagitis, Crohn's disease, ulcerative colitis, irritable bowel syndrome (IBS) and celiac disease. T-test was used to compare continuous variables and a Chi-square test was used for categorical variables. Multivariate logistic regression models were used to assess the association between PsA and GI comorbidities. PsA was associated with Crohn's disease (OR 2.4, 95 %CI: 1.75-3.32, p < 0.0001), ulcerative colitis (OR 2.1, 95 %CI: 1.33-3.26, p = 0.001), reflux esophagitis (OR 1.6, 95 %CI: 1.44-1.78, p < 0.0001), PUD (OR 1.5, 95 %CI: 1.31-1.63, p < 0.0001) and IBS (OR 1.4, 95 %CI: 1.01-1.86, p = 0.045). After controlling for known risk factors, the association remained significant between PsA and Crohn's disease (OR 2.2, 95 %CI: 1.59-3.03, p < 0.0001), ulcerative colitis (OR 1.9, 95 %CI: 1.21-3.00, p = 0.005), reflux esophagitis (OR 1.5, 95 %CI: 1.31-1.63, p < 0.0001), and PUD (OR 1.3, 95 %CI: 1.12-1.47, p < 0.0001). No significant association was found between PsA and celiac disease. In the current study PsA was associated with gastrointestinal morbidities including Crohn's disease, ulcerative colitis, PUD and IBS. Physicians treating patients with PsA should be aware of these associations.

The Influence of Antral Ulcers on Intramural Gastric Nerve Projections Supplying the Pyloric Sphincter in the Pig (Sus scrofa domestica)-Neuronal Tracing Studies

Background

Gastric ulcerations in the region of antrum pylori represent a serious medical problem in humans and animals. Such localization of ulcers can influence the intrinsic descending nerve supply to the pyloric sphincter. The pyloric function is precisely regulated by intrinsic and extrinsic nerves. Impaired neural regulation could result in pyloric sphincter dysfunction and gastric emptying malfunction. The aim of the study was to determine the effect of gastric antral ulcerations on the density and distribution of intramural gastric descending neurons supplying the pyloric sphincter in pigs.

Methodology/Principal Findings

The experiment was performed on 2 groups of pigs: healthy gilts (n=6) and gilts with experimentally induced peptic ulcers in the region of antrum pylori (n=6). Gastric neurons supplying pyloric sphincter were labeled using the retrograde neuronal tracing technique (20μl of Fast Blue tracer injected into the pyloric sphincter muscle). After a week survival period the animals were sacrificed and the stomachs were collected. Then, the stomach wall was cross-cut into 0.5cm thick sections taken in specified intervals (section I - 1.5cm; section II - 3.5cm; section III - 5.5cm; section IV – 7.5cm) starting from the sphincter. Consecutive microscopic slices prepared from each section were analyzed under fluorescent microscope to count traced neurons. Obtained data were statistically analyzed. The total number of FB-positive perikarya observed within all studied sections significantly decreased from 903.3 ± 130.7 in control to 243.8 ± 67.3 in experimental animals. In healthy pigs 76.1 ± 6.7% of labeled neurons were observed within the section I, 23.53 ± 6.5% in section II and only occasional cells in section III. In experimental animals, as many as 93.8 ± 2.1% of labeled cells were observed within the section I and only 6.2 ± 2.2% in section II, while section III was devoid of such neurons. There were no traced perikarya in section IV observed in both groups of pigs.

Conclusions/Significance

Obtained results revealed for the first time significant impact of antral ulcerations on intramural descending nerve pathways supplying the pyloric sphincter in pigs, animals of increasing value in biomedical research and great economic importance.

Quantitative stain-free and continuous multimodal monitoring of wound healing in vitro with digital holographic microscopy

Impaired epithelial wound healing has significant pathophysiological implications in several conditions including gastrointestinal ulcers, anastomotic leakage and venous or diabetic skin ulcers. Promising drug candidates for accelerating wound closure are commonly evaluated in in vitro wound assays. However, staining procedures and discontinuous monitoring are major drawbacks hampering accurate assessment of wound assays. We therefore investigated digital holographic microscopy (DHM) to appropriately monitor wound healing in vitro and secondly, to provide multimodal quantitative information on morphological and functional cell alterations as well as on motility changes upon cytokine stimulation. Wound closure as reflected by proliferation and migration of Caco-2 cells in wound healing assays was studied and assessed in time-lapse series for 40 h in the presence of stimulating epidermal growth factor (EGF) and inhibiting mitomycin c. Therefore, digital holograms were recorded continuously every thirty minutes. Morphological changes including cell thickness, dry mass and tissue density were analyzed by data from quantitative digital holographic phase microscopy. Stimulation of Caco-2 cells with EGF or mitomycin c resulted in significant morphological changes during wound healing compared to control cells. In conclusion, DHM allows accurate, stain-free and continuous multimodal quantitative monitoring of wound healing in vitro and could be a promising new technique for assessment of wound healing.

Murine endoscopy for in vivo multimodal imaging of carcinogenesis and assessment of intestinal wound healing and inflammation

Mouse models are widely used to study pathogenesis of human diseases and to evaluate diagnostic procedures as well as therapeutic interventions preclinically. However, valid assessment of pathological alterations often requires histological analysis, and when performed ex vivo, necessitates death of the animal. Therefore in conventional experimental settings, intra-individual follow-up examinations are rarely possible. Thus, development of murine endoscopy in live mice enables investigators for the first time to both directly visualize the gastrointestinal mucosa and also repeat the procedure to monitor for alterations. Numerous applications for in vivo murine endoscopy exist, including studying intestinal inflammation or wound healing, obtaining mucosal biopsies repeatedly, and to locally administer diagnostic or therapeutic agents using miniature injection catheters. Most recently, molecular imaging has extended diagnostic imaging modalities allowing specific detection of distinct target molecules using specific photoprobes. In conclusion, murine endoscopy has emerged as a novel cutting-edge technology for diagnostic experimental in vivo imaging and may significantly impact on preclinical research in various fields.

Collagen matrix-bound clotting factors (CMBCF) promote healing-associated events independent of factor XIII in an in vitro model

We have previously explored in vitro as well as in vivo models of the biological effects of liquid fibrin glue (FG) containing factor XIII. The fixed combination of a collagen matrix and coagulation factors I and IIa (TachoSil(®) , Nycomed, Linz, Austria) is void of factor XIII. We aimed to determine whether (1) this preparation exerts similar effects to liquid FG on cells in an in vitro system, or (2) this effect is modulated by factor XIII. In an in vitro model, the effect of the fixed combination of collagen matrix and coagulation factors I and IIa (collagen matrix-bound clotting factor [CMBCF]) on the expression and secretion of growth factors (vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factor-2) by gastric epithelial (AGS) and mesenchymal cells (fibroblasts), as well as their proliferative response (WST-test), was compared in the presence and absence of factor XIII. The use of CMBCF compared with collagen type I matrix resulted in an increased proliferation rate of fibroblasts; there was an increased secretion of fibroblast growth factor-2. Gastric epithelial cells secreted more vascular endothelial growth factor and platelet-derived growth factor into the culture supernatant in the presence of CMBCF. All responses remained unaltered by the addition of factor XIII in different concentrations. In conclusion, CMBCF exerted effects similar to liquid FG in an in vitro model of healing. The addition of factor XIII did not alter the response of mesenchymal or epithelial cells, with respect to proliferation and growth factor secretion.

Gastric juice acidity in upper gastrointestinal diseases

AIM: To search the independent factors determining gastric juice acidity and to investigate the acidity of gastric juices in various benign and malignant upper gastrointestinal diseases.

METHODS: Fasting gastric juice acidity of 165 healthy subjects and 346 patients with esophageal ulcer (n = 21), gastric ulcer (n = 136), duodenal ulcer (n = 100) or gastric cancer (n = 89) were measured and compared. Additionally, gastric specimens were taken from the antrum and body for rapid urease test and histological examination.

RESULTS: Multivariate analysis revealed that bile stain of gastric juice, high acute inflammatory score of the corpus, and atrophy of the corpus were independent risk factors for the development of gastric hypoacidity with odds ratios of 3.1 (95% CI: 1.3-7.3), 3.1 (95% CI: 1.2-7.9) and 3.5 (95% CI: 1.3-9.2). Esophageal ulcer and duodenal ulcer patients had a lower pH level (1.9 and 2.1 vs 2.9, both P < 0.05) of gastric juices than healthy subjects. In contrast, gastric ulcer and gastric cancer patients had a higher pH level (3.4 and 6.6 vs 2.9, both P < 0.001) than healthy controls. Hypoacidity existed in 22%, 5%, 29%, 5% and 88% of healthy subjects, esophageal ulcer, gastric ulcer, duodenal ulcer and gastric cancer patients, respectively.

CONCLUSION: Bile reflux, atrophy and dense neutrophil infiltrate of the corpus are three independent factors determining the acidity of gastric juice.

Antacid effects of Chinese herbal prescriptions assessed by a modified artificial stomach model

AIM: To assess the antacid effects of the tonic Chinese herbal prescriptions, Si-Jun-Zi-Tang (SJZT) and Shen-Ling-Bai-Zhu-San (SLBZS).

METHODS: Decoctions of the tonic Chinese herbal prescriptions, SJZT and SLBZS, were prepared according to Chinese original documents. The pH of the prescription decoctions and their neutralizing effects on artificial gastric acids were determined and compared with water and the active controls, sodium bicarbonate and colloidal aluminum phosphate. A modified model of Vatier’s artificial stomach was used to determine the duration of consistent neutralization effect on artificial gastric acids. The neutralization capacity in vitro was determined with the titration method of Fordtran’s model.

RESULTS: The results showed that both SJZT and SLBZS have antacid effects in vitro. Compared with the water group, SJZT and SLBZS were found to possess significant gastric acid neutralizing effects. The duration for consistent neutralization of SLBZS was significantly longer than that of water. Also, SLBZS and SJZT exhibited significant antacid capacities compared to water.

CONCLUSION: SJZT and SLBZS were consistently active in the artificial stomach model and are suggested to have antacid effects similar to the active control drugs.

Nondiarrheal Disorders of the Gastrointestinal Tract in Neonatal Foals

Neonates can have a variety of gastrointestinal disorders, primary and secondary in nature. Important primary disorders include con-genital abnormalities and meconium retention. One of the most important secondary lesions is generalized ileus. Gastric ulceration can occur as a primary or secondary event. This article addresses the pathophysiology, diagnosis, and treatment of gastrointestinal problems commonly observed in neonatal foals.

Review article: relief of symptoms in gastric acid-related diseases--correlation with acid suppression in rabeprazole treatment

Symptom relief is one of the key goals in the management of gastric acid-related disorders such as gastro-oesophageal reflux disease (GERD), including nonerosive reflux disease (NERD), and duodenal and gastric ulcer. Whereas heartburn and regurgitation are classic symptoms of GERD, duodenal and gastric ulcers are associated with epigastric pain. The relationship between gastric acid and the presence of symptoms correlates well in GERD and duodenal ulcer, but not in gastric ulcer and NERD. Nevertheless, in all these disorders, gastric acid is considered a key pathogenic element, and acid suppression remains central to therapy. With their profound, prolonged effect on acid inhibition, proton pump inhibitors are considered the first-choice therapy for these disorders. Rabeprazole is a newer generation proton pump inhibitor that suppresses the gastric proton pump and acid secretion more rapidly than does omeprazole, lansoprazole or pantoprazole. In clinical trial settings, rabeprazole provided fast and sustained symptom relief, which can help ensure patient acceptance of therapy and aid in patient compliance.

Intragastric pH in critically ill neonatal foals and the effect of ranitidine

OBJECTIVE

To characterize intragastric pH profiles in critically ill foals and determine whether administration of ranitidine altered pH profiles.

DESIGN

Prospective observational study.

ANIMALS

23 hospitalized neonatal foals < or = 4 days of age.

PROCEDURE

Intragastric pH was measured continuously for up to 24 hours by use of an indwelling electrode and continuous data recording system. In 21 foals, ranitidine was administered IV.

RESULTS

10 foals had predominantly or exclusively alkaline profiles, 10 had profiles typical of those reported for healthy foals, with periods of acidity (hourly mean pH < 5.0 at least once), and 3 had atypical profiles with periods of acidity. All 10 foals that had intragastric pH profiles typical of healthy foals survived, whereas only 2 foals with alkaline profiles survived, and none of the foals with atypical profiles survived. The effects of ranitidine administration could not be assessed in 13 foals because of a high baseline intragastric pH. In 7 of the remaining 9, ranitidine administration resulted in an alkalinizing response, but this response was often of blunted duration. Ranitidine administration did not appear to alter the intragastric pH profile in the remaining 2 foals.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that hospitalized critically ill foals often have intragastric pH profiles different from those reported for healthy foals and may respond differently to ranitidine administration than do healthy foals. Many critically ill foals have continuously alkaline intragastric pH profiles, questioning the need for prophylactic administration of ranitidine in all critically ill foals.

Clinical and endoscopic aspects in the evolution of patients with bleeding peptic ulcer--a cohort study

BACKGROUND

Bleeding ulcers are a major problem in public health and represent approximately half of all the cases of upper gastrointestinal hemorrhage in the United States. This study aims to determine the prognostic value of factors such as clinical history, laboratory and endoscopic findings in the occurrence of new episodes of bleeding in patients who have upper gastrointestinal hemorrhage caused by gastric or duodenal peptic ulcer.

METHODS

A cohort study with 94 patients was designed to investigate prognostic factors to the occurrence of new episodes of bleeding.

RESULTS

From the 94 patients studied, 88 did not present a new bleeding episode in the 7 days following hospital admission. The incidence of rebleeding was significantly higher in those patients with hemoglobin < 6 g/dL at the admission (P = 0.03, RR = 6.2). The localization of the ulcers in bulb was positively associated to rebleeding (P = 0.003). The rebleeding group needed a greater number of units transfunded (P = 0.03) and the time of hospitalization was longer than the time of the hemostasia group (P = 0.0349).

CONCLUSIONS

The identification of patients with risk of death by bleeding peptic ulcer remains as a challenge, once few factors are capable of predicting the severity of the evolution. The identification of such factors will allow the choice of the better therapeutic conduct improving the diagnosis and decreasing the rate of rebleeding and the mortality.

Immunocytochemical and in situ hybridization studies of gastrin after cisplatin treatment

Cisplatin treatment (9 mg/kg) causes bloating of the stomach, an increase in gastric acid, and ulceration in rats. Gastrin, a gut peptide, plays an important role in regulating gastric acid production. To study the role of gastrin in this increased gastric acid production after cisplatin treatment, male Wistar rats (100-150 g) were treated with cisplatin (9 mg/kg) in five divided doses over 5 consecutive days. The rats were sacrificed 1, 6, 10, or 15 days after the last treatment. As measured by immunocytochemistry, in situ hybridization, Northern blot, and dot-blot techniques, gastrin was found to be below detectable limits just 1 day after cisplatin treatment. However, 10-15 days after the last injection, the levels for both gastrin and its mRNA gradually recovered to normal. Northern blot studies showed that decreased somatostatin mRNA parallels the changes of gastrin and its mRNA. These results suggest that after cisplatin treatment the increased gastric acid production in rat stomach is independent of gastrin. This decrease of gastrin production is not under the influence of somatostatin, which also decreased after cisplatin treatment.

Gastric metaplasia of the duodenum: identification by an endoscopic selective mucosal staining technique

BACKGROUND

To understand the pathophysiology of duodenal ulcer disease, it is important to identify and quantitate gastric metaplasia of the duodenum. Methylene blue dye is absorbed well by intestinal mucosa, but not by gastric mucosa. Our aim was to validate a methylene blue staining technique for measurement of gastric metaplasia in the duodenum.

METHODS

Eight subjects with chronic duodenal ulcer disease and seven subjects with other upper intestinal disorders underwent duodenal methylene blue staining after application of a mucolytic agent. Biopsy specimens were obtained from blue-stained and pale unstained areas and assessed for gastric metaplasia histologically.

RESULTS

Pink or pale unstained duodenal areas had more gastric surface cell metaplasia than blue-stained areas. Unstained duodenum was also more likely to have extensive (more than 25% of the biopsy specimens) gastric metaplasia (60%) than blue-stained areas (9%). Subjects with duodenal ulcer disease had more unstained mucosa than controls.

CONCLUSION

Methylene blue staining of the duodenum is useful to identify and quantitate gastric metaplasia.

Duodenal erosions and ulcers in patients with pancreatobiliary obstruction

In order to determine whether obstructive pancreatobiliary lesions increase the risk of duodenal erosions and ulcers, the duodenal mucosa of patients with these lesions were prospectively examined before endoscopic retrograde cholangiopancreatography (ERCP). During the study period, 133 patients underwent ERCP for various reasons in the Department of Medicine, The Aga Khan University Hospital. One hundred and twenty-three patients were eligible for final analysis. Sixty-five patients with bilirubin > or = 35 mumol/L and alkaline phosphatase > or = 2.5 times normal levels along with radiological evidence of pancreatobiliary obstruction were included in the obstruction group. Fifty-eight patients who did not fulfil these criteria were used in the control group. Acid peptic lesions, which included erosions and ulcers, were seen in 16 patients of the obstruction group and four patients of the control group (P = 0.016, odds ratio (OR) = 4.41). Patients with carcinoma of the pancreas had a greater number of lesions than the rest of the obstruction group (P = 0.001, OR = 8.75). Individual variables like age, sex, serum bilirubin, alanine aminotransferase, alkaline phosphatase, amylase levels, and duration of jaundice did not increase the vulnerability to acid peptic injury. The degree of obstruction multiplied by duration of jaundice (alkaline phosphatase x days) increased the susceptibility for duodenal disease (P = 0.047). From this data it was concluded that patients with obstructive pancreatobiliary lesions are more prone to acid peptic duodenal lesions.

Use of animal models in peptic ulcer disease

Considerable progress has been made in the understanding of the formation of gastric erosions by the use of animals. The role of gastric acid secretion in their pathogenesis has been clarified. Gastric erosions are associated with the presence of acid in the stomach and slow gastric contractions. With several different experimental procedures, the animal's body temperature falls; preventing the fall averts erosions. A fall in body temperature or exposure to cold are associated with the secretion of thyrotropin-releasing hormone (TRH), and both increased and decreased concentration of corticotropin-releasing factor (CRH) in discrete regions of rat brains. Thyrotropin-releasing hormone when injected into specific sites in the brain produces gastric erosions and increases acid secretion and slow contractions, whereas CRH has the opposite effects. One of the major sites of interaction of the two peptides is in the dorsal motor complex of the vagus nerve. Thyrotropin-releasing hormone increases serotonin (5-HT) secretion into the stomach. Serotonin counter-regulates acid secretion and slow contractions. Many other peptides injected into discrete brain sites stimulate or inhibit gastric acid secretion.

Diurnal variation in intragastric pH in children with and without peptic ulcers

Diurnal variation in intragastric pH in children with peptic ulcers has not been previously reported. Therefore, we monitored intragastric pH during a 24-h period in 82 subjects (10 children with gastric ulcers, 9 children with duodenal ulcers, 58 non-ulcer (comparison group) children, and 5 healthy adults) using a monopolar glass pH electrode. The percent of readings below pH 2, 3, 4, and 5 for each subject was calculated and compared between the comparison group and the two ulcer groups using means and slopes (i.e. changes in percent with age for each group) of percent readings for each pH analysis. In the comparison group children, gastric acidity increased with age and reached adult levels by 14 y. Mean readings for all pH analyses in gastric ulcer children were lower than those in age-adjusted comparison children (p < 0.05). The slopes of the relationships between age and the percent time below any pH for the gastric ulcer group were different from those in the comparison group (p < 0.05) and were negative for all pH analyses. The mean time below pH 2 in children with duodenal ulcers was greater than that in age-adjusted comparison children (p = 0.002). The slope of the relationship between age and the percent time below pH 2 in the duodenal ulcer group was different from that in the comparison group (p < 0.05). Gastric acidity in children with primary gastric ulcers was reduced during childhood, but in children with primary duodenal ulcer, gastric acidity was at or above adult levels.

Are tryptase and cathepsin D related to Helicobacter pylori infection and mucosal gastrin in peptic ulcer?

The pathogenesis of peptic ulcer is a complex phenomenon and several factors are thought to be involved in this process. Among others, Helicobacter pylori infection, hypergastrinaemia and some proteases seem to play an essential role in inducing peptic ulceration. We investigated whether tryptase (a serine endoprotease released by mast cells) and cathepsin D (a lysosomal hydrolase which seems able to derange the extracellular matrix) play a part in peptic ulcer disease and whether they are linked to Helicobacter pylori infection and mucosal content of gastrin. We studied 13 controls, 25 patients with gastric ulcer, 47 with duodenal ulcer and 11 with duodenitis. Tryptase and cathepsin D were measured in mucosal biopsy specimens (body and antrum of the stomach and duodenum) using IRMA methods. Gastrin was assayed in the antral mucosa by means of a RIA method. Helicobacter pylori infection was histologically evaluated (Giemsa). Tryptase and cathepsin D levels were higher (25%) in patients with active peptic ulcer, whether gastric or duodenal. The mucosal content of cathepsin D, but not that of tryptase, was associated with Helicobacter pylori infection. Tryptase, on the other hand, was related to gastrin content. No correlation was found between the two enzymes. It is concluded that tryptase and cathepsin D probably reflect different pathophysiological modifications in ulcer disease. Cathepsin D seems to be mainly related to the phlogistic reaction of the mucosa to Helicobacter pylori infection; tryptase may reflect and indirect link between the action of gastrin and the function of mast cells.

Third compartment ulcers in the llama

The diagnosis of third compartment ulcers in the llama and alpaca is largely one of exclusion. Clinical signs may include mild to severe colic, inappetence, decreased fecal output, bruxism, and depression. Abdominocentesis results are usually unremarkable if C3 perforation has not occurred but reflective of a generalized peritonitis if full thickness ulceration has occurred. The H-2 receptor antagonists cimetidine and ranitidine do not suppress C3 acid production for a significant period of time and are of questionable efficacy in the management of C3 ulcers.

Role of Helicobacter pylori in cirrhotic patients with peptic ulcer. A serological study

Helicobacter pylori was found to be a promoter factor of peptic ulcer that has an incidence higher in patients with hepatic cirrhosis. To clarify the role between H. pylori and peptic ulcer in patients with hepatic cirrhosis, a serological test (ELISA test, HEL-p, AMRAD, Australia), was used to measure the presence of H. pylori of patients with hepatic cirrhosis. Within two years, 108 cirrhotic patients who had received a panendoscopic examination were enrolled in this study. There were 79 males and 27 females with a mean age of 53.2 years. Sixty-four cases had positive serum HBsAg and 44 had negative serum. The results showed that the prevalence of Helicobacter pylori in cirrhosis was 43.5% (47/108). There was no difference of HEL-p-positive rate between peptic ulcer and normal gastroduodenal mucosa (45.2% vs 46.1%, P > 0.05). According to this study, there appears to be no relation between peptic ulcer and H. pylori in patients with hepatic cirrhosis. The etiology of peptic ulcer in cirrhotic patients need further study.

Diurnal profile of oxyntomodulin-like immunoreactivity in duodenal ulcer patients

Plasma concentrations of oxyntomodulin-like immunoreactivity, a group of intestinal peptides capable of mediating an enterogastrone signal, were measured during a 24-h period in 6 duodenal ulcer patients and compared with those of 16 age-matched controls. Each subject was submitted to 18 oxyntomodulin-like immunoreactivity determinations. Four standardized meals were given during the test. Furthermore, each patient was evaluated for peak acid output after pentagastrin stimulation. The values of the duodenal ulcer subjects were predominantly within normal acid secretion limits. Fasting levels, meal-induced variations, and nocturnal production of oxyntomodulin-like immunoreactivity were similar in the two groups. A negative correlation was observed between peak acid output and oxyntomodulin-like immunoreactivity evaluated either as nocturnal production or as maximum nyctohemeral concentration. We conclude that, taken as a whole, duodenal ulcer disease is not caused by a defect in oxyntomodulin-like immunoreactivity secretion. However, this study does not rule out the possibility of a selective deficiency of these peptides in some duodenal ulcer subgroups such as hypersecretory patients.

Peptic ulcer disease: an update

Peptic ulcers can develop when there is an imbalance between gastric acid secretion and gastroduodenal mucosal defense. Investigators are looking at the role of Helicobacter pylori in the development of peptic ulcer disease; eradication of the microorganism may reduce recurrence. Approved drug therapy includes H2-receptor antagonists, omeprazole, sucralfate, and antacids. Recommendations for treating and counseling patients are provided.