Prevalence of achlorhydria in an Asian population detected using Congo red staining during routine gastroscopy: 22 years' experience from a single centre.

OBJECTIVE: We aimed to study the prevalence of achlorhydria (AC) in a large Asian population. DESIGN: Medical records of patients who underwent oesophagogastroduodenoscopy (OGD) with Congo red staining method at the Vichaiyut Hospital from January 2010 to December 2019 were retrospectively reviewed. RESULTS: A total of 3597 patients was recruited; 223 were excluded due to concurrent use of proton pump inhibitors. Eighteen from 3374 patients (0.53%) had AC. Seven patients were presented with permanent AC (5F, 2M) (median age=69 years; range 58-92). Among 11 patients with temporary AC (5M, 6F: mean age 73.4 years; SD 13.2 years), all had gastrointestinal Helicobacter pylori bacterial infection and were over 45 years old. After successful treatment for H. pylori, AC was absent among patients with temporary AC. If counting only patients over 45 years of age, the prevalence of AC was 0.68% (18/2614). No adverse events arising from Congo red occurred. CONCLUSION: AC is relatively rare. Permanent and temporary AC were found only when they were over 55 and 45 years old, respectively. Staining Congo red on gastric mucosa can be safely and routinely incorporated into the OGD procedure for early detection of AC. We recommended a low-cost screening test such as serum vitamin B levels for screening only in patients aged 50 and over.

Non-invasive method for the assessment of gastric acid secretion.

Methods for the measure of gastric acid secretion include invasive and non-invasive tests. The gold-standard to measure the acid output is the collection of gastric after in basal condition (Basal Acid Output, B.A.O.) and after an i.m. injection of pentagastrin (Maximal Acid Output, M.A.O.). However, direct measurement of gastric acid production is out of order in clinical practice, but many GI symptoms are claimed to be related with acid disorders and empirically cured. Hypochlorhydria is associated with precancerous conditions such as chronic atrophic gastritis (CAG). Acid measurement with non-invasive methods (pepsinogens) is supported by international guidelines.

Helicobacter pylori, HIV and Gastric Hypochlorhydria in the Malawian Population.

BACKGROUND: HIV and Helicobacter pylori are common chronic infections in sub-Saharan Africa. Both conditions can predispose to gastric hypochlorhydria that may be a risk factor for enteric infections and reduced drug absorption. We have investigated to what extent HIV and H. pylori infections are associated with hypochlorhydria in a Malawian cohort of patients undergoing endoscopy. METHODS: 104 sequential symptomatic adults referred for gastroscopy at Queen Elizabeth Central Hospital, Blantyre, Malawi, had blood taken for rapid HIV testing and fasting serum gastrin analysis. Gastric fluid was aspirated for pH testing, and gastric biopsies were taken. RESULTS: After 9/104 HIV-infected patients who were already established on anti-retroviral therapy were excluded, 17/95 (25.0%) were seropositive for untreated HIV, and 68/95 (71.6%) patients were H. pylori positive by histology. Hypochlorhydria (fasting gastric pH>4.0) was present in 55.8% (53/95) of patients. H. pylori infection was significantly associated with hypochlorhydria (OR 2.91, [1.02-7.75], p=0.046). While single infection with HIV was not significantly independently associated with hypochlorhydria. H. pylori and HIV co-infection was more strongly associated with hypochlorhydria (OR 6.25, [1.33-29.43], p=0.020) than either infection alone, suggesting an additive effect of co-infection. HIV infection was associated with higher serum gastrin levels (91.3 pM vs. 53.1 pM, p=0.040), while H. pylori infection was not (63.1 pM vs. 55.1 pM, p=0.610). Irrespective of H. pylori and HIV status, most patients (>90%) exhibited pangastritis. Only three patients had histological evidence of gastric atrophy, of which only one was HIV-infected. CONCLUSION: H. pylori infection was associated with fasting hypochlorhydria, while HIV was not independently associated. HIV and H. pylori co-infection, however, was more strongly associated with hypochlorhydria than H. pylori infection alone. The mechanism of this apparent additive effect between HIV and H. pylori remains unclear, but appears to be related to chronic pangastritis rather than gastric atrophy, and associated with hypergastrinaemia in HIV-infected individuals.

Helicobacter pylori-associated hypochlorhydria in children, and development of iron deficiency.

AIMS: Acute Helicobacter pylori infection is associated with transient hypochlorhydria. In H pylori-associated atrophy, hypochlorhydria has a role in iron deficiency (ID) through changes in the physiology of iron-complex absorption. The aims were to evaluate the association between H pylori-associated hypochlorhydria and ID in children. METHODS: Symptomatic children (n=123) were prospectively enrolled. Blood, gastric juice and gastric biopsies were taken, respectively, for haematological analyses, pH assessment and H pylori determination, and duodenal biopsies for exclusion of coeliac disease. Stool samples were collected for parasitology/microbiology. Thirteen children were excluded following parasitology and duodenal histopathology, and five due to impaired blood analysis. RESULTS: Ten children were hypochlorhydric (pH>4) and 33 were H pylori positive. In H pylori-positive children with pH>4 (n=6) serum iron and transferrin saturation levels % were significantly lower (p<0.01) than H pylori-positive children with pH≤4. No differences in ferritin, or total iron binding capacity, were observed. In H pylori-negative children with pH>4, iron and transferrin saturation were not significantly different from children with pH≤4. CONCLUSIONS: Low serum iron and transferrin in childhood H pylori infection is associated with hypochlorhydria. In uninfected children, hypochlorhydria was not associated with altered serum iron parameters, indicating a combination of H pylori infection and/or inflammation, and hypochlorhydria has a role in the aetiology of ID. Although H pylori-associated hypochlorhydria is transient during acute gastritis, this alters iron homeostasis with clinical impact in developing countries with a high H pylori prevalence.

Measurement of gastric pH in ambulatory esophageal pH monitoring.

BACKGROUND: Ambulatory esophageal pH monitoring is the method used most widely to quantify gastroesophageal reflux. The degree of gastroesophageal reflux may potentially be underestimated if the resting gastric pH is high. Normal subjects and symptomatic patients undergoing 24-h pH monitoring were studied to determine whether a relationship exists between resting gastric pH and the degree of esophageal acid exposure. METHODS: Normal volunteers (n = 54) and symptomatic patients without prior gastric surgery and off medication (n = 1,582) were studied. Gastric pH was measured by advancing the pH catheter into the stomach before positioning the electrode in the esophagus. The normal range of gastric pH was defined from the normal subjects, and the patients then were classified as having either normal gastric pH or hypochlorhydria. Esophageal acid exposure was compared between the two groups. RESULTS: The normal range for gastric pH was 0.3-2.9. The median age of the 1,582 patients was 51 years, and their median gastric pH was 1.7. Abnormal esophageal acid exposure was found in 797 patients (50.3%). Hypochlorhydria (resting gastric pH >2.9) was detected in 176 patients (11%). There was an inverse relationship between gastric pH and esophageal acid exposure (r = -0.13). For the patients with positive 24-h pH test results, the major effect of gastric pH was that the hypochlorhydric patients tended to have more reflux in the supine position than those with normal gastric pH. CONCLUSION: There is an inverse, dose-dependent relationship between gastric pH and esophageal acid exposure. Negative 24-h esophageal pH test results for a patient with hypochlorhydria may prompt a search for nonacid reflux as the explanation for the patient's symptoms.

Detection of early abnormalities in gastric function in first-degree relatives of patients with pernicious anemia.

BACKGROUND: Pernicious anemia (PA), as many other autoimmune disorders, has a trend to appear in other members of the family of the affected patients. Although this fact has been recognized since some decades ago, less is known about the frequency with which the abnormalities detected in the patients appear also in their relatives, the correlations that exist among these abnormalities and to what extent these markers of the disease relate to serum cobalamin concentration. SUBJECTS AND RESULTS: For these reasons we studied the values of some markers of PA in a group of 79 first-degree relatives and we detected that the most frequent abnormalities are a decrease in serum pepsinogen I (22.7% of cases), an increase in serum gastrin (16.5% of cases) and in parietal cell antibody at a titer >or=40 (23.4% of cases). From a functional point of view, a decrease in hydrogen excretion in a magnesium breath test, indicative of achlorhydria, is also frequent (29.1%). The fall in cobalamin concentration runs in parallel with these abnormalities. The concentration of this vitamin was below normal levels in as much as 15.2% of cases. CONCLUSION: These findings emphasize the need for searching for the presence of occult or latent PA in relatives of patients with this diagnosis, not only to prevent the development of anemia but also to avoid other undesirable consequences of cobalamin deficiency.

Validation of the blood quininium resin test for assessing gastric hypochlorhydria.

Although gastric hypochlorhydria is a risk factor for gastroenteritis and for gastric cancer, no reliable, inexpensive, noninvasive test exists for screening or epidemiologic studies. We aimed to evaluate the sensitivity and specificity of the blood quininium resin test (bQRT) for hypochlorhydria, against pH monitoring. Twelve fasting adult volunteers-seven with and five without H. pylori infection-ingested 80 mg/kg of quininium resin twice, once with and once without acid suppression. Gastric pH was monitored for 75 minutes; serum samples were obtained at times 0 and 75 minutes. The bQRT levels were compared to gastric pH, controlling for omeprazole use and H. pylori infection. Subjects with a median recorded pH > or =3.5 were considered hypochlorhydric. Using a bQRT level of 10 as a cutoff for hypochlorhydria, the sensitivity and specificity of the bQRT were 100% and 37.5%, respectively. The bQRT predicted omeprazole use more accurately than pH monitoring. In conclusions, The bQRT has a high sensitivity for hypochlorhydria, making it potentially useful in populations with a high prevalence of hypochlorhydria. In its current formulation, the bQRT's low specificity makes it less useful in low-risk population.

[Iron deficiency: not always blood losses]. / Ferropenia: no siempre son pérdidas.

UNLABELLED: Iron deficiency may be the only presenting sign of malabsorption due to the presence of intestinal villous atrophy. Once gastrointestinal blood losses have been excluded, intestinal malabsorption should be investigated. OBJECTIVES: To determine the utility of jejunal biopsy in the evaluation of iron deficiency due to a defective absorption and the different diseases that may cause malabsortive iron deficiency. METHODS: Seventy patients with iron deficiency (ferritin<25 ng/ml), referred to the Unitat de Proves Funcionals Digestives to perform a jejunal biopsy were included. Jejunal biopsy was obtained distal to Treitz with a Watson capsule. Histological changes were classified according to the criteria proposed by Marsh. RESULTS: Jejunal biopsy was performed in 66 patients. Histology was normal in 25, unespecific in 1, showed inflammatory infiltrate in 12, hyperplastic changes in 2 and atrophy in 25. In one patient showed intestinal giardiasis. The clinical diagnosis was celiac sprue in 21 patients (32%), aclorhydria in 7 (10.5%), bacterial overgrowth in 1 (1.5%), intestinal giardiasis in 1 (1.5%), menstrual blood loss in 1 (1.5%) and 35(53%) patients remained without a definitive diagnosis. CONCLUSIONS: Jejunal biopsy is useful in the evaluation of iron deficiency due to intestinal malabsorption and reveals intestinal abnormalities in a significant number of cases.

Evaluation of gastric acid secretion at endoscopy with a modified Congo red test.

BACKGROUND: Markedly decreased or absent gastric acid production is associated with a number of clinically significant conditions, and identification of patients with hypo/achlorhydria may be important. However, current methods of assessing impaired acid secretion are unreliable, time-consuming, and/or complex. The aim of this prospective study was to evaluate a modified endoscopic Congo red test for the diagnosis of hypo/achlorhydria by correlation with a standard gastric acid secretory test. METHODS: One hundred six consecutive outpatients with or without dyspeptic symptoms referred for endoscopy were evaluated by using a modified endoscopic Congo red test and a standard test of gastric acid secretion. The modified endoscopic Congo red test suggested hypo/achlorhydria when there was no color shift or a shift of small extent (less than one third of fundic mucosa). Hypo/achlorhydria by the standard gastric acid secretory test was defined as a maximal acid output of less than 6.9 mmol/hour in men and 5.0 mmol/hour in women. RESULTS: The accuracy of the modified endoscopic Congo red test for the diagnosis of hypo/achlorhydria was 0.98 (95% CI [0.93, 0.99]). The sensitivity was 1.0 (95% CI [0.92, 1.00]) and specificity 0.96 (95% CI [0.88, 0.99]). All patients tolerated the modified endoscopic Congo red test well. CONCLUSION: The modified endoscopic Congo red is an accurate, simple, fast, inexpensive, and well-tolerated chromoendoscopic method for identification of patients with hypo/achlorhydria during routine upper endoscopy.

A modification of the quininium resin test for assessing gastric acidity.

BACKGROUND: Gastric acid is an important defence against enteric infection. Studies investigating the relationship between hypochlorhydria and enteric infections or gastric malignancy have been limited by difficulties in the non-invasive measurement of gastric acidity. AIM: To develop a blood test for hypochlorhydria based on the quininium resin test. METHODS: Quininium resin dissociates to liberate free quinine at pH

Acute gastritis with hypochlorhydria: report of 35 cases with long term follow up.

BACKGROUND: Between 1976 and 1987, 35 cases of acute gastritis with hypochlorhydria (AGH) were seen in our research laboratory. The aims of this study were to determine the natural history of AGH and the role of Helicobacter pylori in its pathogenesis. METHODS: Archived serum and gastric biopsy samples obtained from AGH subjects were examined for evidence of H pylori colonisation. Twenty eight of 33 (85%) surviving AGH subjects returned a mean of 12 years after AGH for follow up studies, including determination of H pylori antibodies, basal and peak acid output, endoscopy, and gastric biopsies. A matched control group underwent the same studies. RESULTS: Archived material provided strong evidence of new H pylori acquisition in a total of 14 subjects within two months, in 18 within four months, and in 22 within 12 months of recognition of AGH. Prevalence of H pylori colonisation at follow up was 82% (23 of 28) in AGH subjects, significantly (p<0.05) higher than in matched controls (29%). Basal and peak acid output returned to pre-AGH levels in all but two subjects. CONCLUSIONS: One of several possible initial manifestations of H pylori acquisition in adults may be AGH. While H pylori colonisation usually persists, hypochlorhydria resolves in most subjects.

Helicobacter pylori infection and chronic gastric acid hyposecretion.

BACKGROUND & AIMS: We have identified a subgroup of Helicobacter pylori-infected subjects with low or absent gastric acid output. The aim of this study was to document the morphological and functional abnormalities in these subjects and to assess the effect of eradicating the infection. METHODS: The 16 hypochlorhydric subjects (6 men) had a mean age of 55 years (range, 36-79 years). They underwent a 14C-urea breath test, H. pylori serology, fasting gastrin, gastric autoantibodies, gastroscopy with antral and body biopsies, and measurement of peak acid output to pentagastrin (PAO(PG)). Their histology was compared with that of age- and sex-matched duodenal ulcer and nonulcer dyspepsia patients (16 each). H. pylori infection was eradicated in the hypochlorhydric subjects, and the investigations were repeated 6 months later. RESULTS: Compared with controls, the hypochlorhydric subjects had less dense H. pylori colonization, body-predominant colonization and gastritis, and increased prevalence of body atrophy and intestinal metaplasia. Median PAO(PG) before eradication in the hypochlorhydric subjects was 1.1 mmol/h and increased to 12.6 mmol/h after eradication (P < 0.001), with no significant change in body atrophy or intestinal metaplasia. CONCLUSIONS: In some subjects, chronic H. pylori infection produces a body-predominant gastritis and profound suppression of gastric acid secretion that is partially reversible with eradication therapy.

Bacteria in biopsies of human hypochlorhydric stomach: a scanning electron microscopy study.

A long-lasting condition of hypochloridria leads to a bacterial growth both in the gastric lumen and biopsies of human stomach. Some of these bacteria are probably involved in gastric carcinogenesis, due to their capacity of nitrosation. This study was carried out on biopsies taken during endoscopy from both gastric antrum and the body of patients with or without hypochloridria. Scanning electron microscopy observation shows that bacteria, other than Helicobacter pylori, found in hypochloridria, can be located not only over but also into and under the mucus layer covering the gastric epithelium. In such areas, mechanical and biochemical damage may occur.

Vitamin B12 deficiency: underdiagnosed, overtreated?

Neurologic damage may become permanent when the disorder is mistaken for multiple sclerosis or diabetic neuropathy--hence the need for prompt parenteral B12 in patients with pernicious anemia. The need for B12 injections is questionable for patients with achlorhydria and for those with a marginal or low serum B12 level but no signs or symptoms of deficiency.

Magnesium hydrogen breath test using end expiratory sampling to assess achlorhydria in pernicious anaemia patients.

A modified magnesium hydrogen breath test, using end expiratory breath sampling, is described to investigate achlorhydria. The efficacy of this test in the diagnostic investigation of pernicious anaemia was compared with that of serum pepsinogen I. Twenty one patients with pernicious anaemia--that is, patients with achlorhydria--and 22 with healed duodenal ulcer and normal chlorhydria were studied. Magnesium hydrogen breath test, serum pepsinogen I, serum gastrin, and standard gastric acid secretory tests were performed in all subjects. The mean (SEM) hydrogen peak value was lower in patients with pernicious anaemia than in the duodenal ulcer group (21.7 (1.9) v 71.3 (5.2) ppm; p = 0.00005). The hydrogen peak value had a 95.2% sensitivity and a 100% specificity to detect pentagastrin resistant achlorhydria. Mean serum pepsinogen I concentrations were also significantly lower in patients with pernicious anaemia than in the duodenal ulcer group (10.7 (2.7) v 123.6 (11.8) micrograms/l p = 0.00005). Sensitivity and specificity to detect pernicious anaemia were both 100% for pepsinogen I. It is concluded that this modified magnesium hydrogen breath test is a simple, noninvasive, cost effective, and accurate method to assess achlorhydria and may be useful in the diagnostic investigation of patients with suspected pernicious anaemia.

Low intramucosal pH is associated with failure to acidify the gastric lumen in response to pentagastrin.

OBJECTIVE: To determine if low gastric intramucosal pH is associated with impaired secretion of gastric acid after pentagastrin stimulation. DESIGN: Prospective study. SETTING: Intensive care unit of a university teaching hospital. PATIENTS: 20 patients requiring mechanical ventilation. INTERVENTIONS: All patients with a gastric luminal pH > 4 were given pentagastrin 6 micrograms/kg s.c. to stimulate gastric acid secretion and the response assessed by further measurements of gastric luminal pH. MEASUREMENTS AND RESULTS: Gastric intramucosal pH (pHi) and luminal pH (pHL) were measured. Patients were divided into two groups on the basis of a low or normal pHi (A value of 7.35 was taken as the lower limit of normal). Patients (n = 6) with normal pHi (7.40 +/- 0.05 [mean +/- SD]) and a luminal pH > 4 (5.65 +/- 1.25) all had a decrease in pHL in response to pentagastrin (decrease in pHL 4.02 +/- 1.52). Of the patients (n = 7) with low pHi (7.2 +/- 0.13) and a pHL > 4 (6.51 +/- 0.48) only one responded to pentagastrin (decrease in pHL for this group 0.93 +/- 1.86). Patients with a pHL < 4 (2.4 +/- 0.71) were not given pentagastrin (n = 7). CONCLUSION: Some critically ill patients with low gastric intramucosal pH appear to have an impaired ability to acidify the gastric lumen in response to pentagastrin.

[Potentiating effect of sodium glutamate on gastric secretion and its possible use as a clinical test]. / Potentsiruiushchee deistvie glutamata natriia na zheludochnuiu sekretsiiu i ego vozmozhnoe ispol'zovanie v kachestve klinicheskogo testa.

The authors report a potentiating effect of sodium glutamate on gastric secretion in subjects free of gastrointestinal diseases. Similar effect has been discovered in dogs. In subjects with gastric hyposecretion (chronic gastritis, functional regulatory disturbances) sodium glutamate combined with pentagastrin is a helpful tool in overall evaluation of gastric secretion. In achlorhydria is can be used for determination of a residual capacity of the stomach to secrete the hydrochloric acid in failure of humoral stimulators.