GastroPanel® Biomarker Assay: The Most Comprehensive Test for Helicobacter pylori Infection and Its Clinical Sequelae. A Critical Review.

BACKGROUND/AIM: Several clinical conditions seriously hamper the diagnostic accuracy of the commonly used tests for Helicobacter pylori (Hp), 13C-urea breath test (UBT) and stool antigen test (SAT). The present communication is a critical review of the potential limitations of UBT and SAT, and describes the approach on how these can be avoided. Drawbacks of the Hp tests: False-negative results are most often due to low bacterial load in the stomach due to: i) use of proton pump inhibitor medication; ii) use of antibiotics; iii) presence of atrophic gastritis and hypoacid stomach; iv); bleeding peptic ulcer; v) gastric cancer (GC) and vi) mucosal-associated lymphatic tissue lymphoma. The UBT also gives false-positive results when urease-producing bacterial species, other than Hp colonize an acid-free stomach. Importantly, neither UBT nor SAT are capable of diagnosing atrophic gastritis, thus missing the patients at highest risk for GC. GastroPanel® (Biohit Oyj, Finland) circumvents these shortcomings with a serological test consisting of a panel of stomach-specific biomarkers: pepsinogen I, pepsinogen II, gastrin-17 and Hp antibodies. GastroPanel® is a tool for non-invasive examination of i) dyspeptic patients for exclusion or diagnosis of Hp or atrophic gastritis, also disclosing the status of gastric acid output; ii) for screening of asymptomatic individuals at risk of GC; and iii) for comprehensive diagnosis of Hp infection. GastroSoft® application integrates the biomarker profile with the patient's medical information, accurately classifying the biomarker profiles into eight diagnostic categories. CONCLUSION: Given that Hp is the single most important risk factor of GC, the non-invasive diagnosis and screening of Hp should be based on more accurate and more comprehensive testing than UBT or SAT alone. The GastroPanel® is such test, being completely devoid of the known serious shortcomings of UBT and SAT.

Serological biomarker testing helps avoiding unnecessary endoscopies in obese patients before bariatric surgery.

BACKGROUND: To assess the value of serological biomarker testing as a substitute for esophagogastroduodenoscopy (EGDS) in pre-operative assessment of patients referred for bariatric surgery. METHODS: Sixty-five obese patients with a mean age of 43 years (range: 21-65) and a mean body mass index (BMI) of 44 (range: 36-59) were studied. The patients were tested with a four-biomarker panel: pepsinogen I and II, gastrin-17 (basal and stimulated), and Helicobacter pylori (HP) antibodies (GastroPanel®, Biohit Oyj, Finland). On the basis of the biomarker test, the patients were classified into the HS (healthy stomach) group (n = 22) with the normal biomarker profile and the NHS (non-healthy stomach) group (n = 43). The classification of patients into HS and NHS was evaluated against the gold standard, i.e. EGDS with biopsies. RESULTS: The concordance (Cohen's kappa) between the biomarker test and gastric histology was 0.68; 95% CI 0.504-0.854, with an overall agreement of 84.6% (95% CI 73.9-91.4%). In the NHS group, all 43 patients had biopsy-confirmed chronic gastritis: 39 non-atrophic HP-gastritis, 4 atrophic antrum gastritis (AGA) of moderate severity.In the HS group only 6 patients had mild superficial H.pylori negative gastritis. Of the 22 HS subjects with the normal biomarker profile, 20 (31% of all 65) had no complaints either, while the remaining two had reflux symptoms with esophagitis. In the NHS group 10 patients had esophagitis and 8 had also reflux symptoms. CONCLUSIONS: The normal biomarker profile is an excellent surrogate for healthy stomach, implicating that pre-operative EGDS could have been avoided in 31% of our asymptomatic bariatric surgery patients who had the normal biomarker profile.

Plasma levels of gastric biomarkers in patients after bariatric surgery: biomarkers after bariatric surgery.

BACKGROUND/AIMS: To investigate the profile of stomach specific biomarkers in blood plasma after bariatric surgery. METHODOLOGY: The study included 20 laparoscopic gastric bypass (LGBP) and 20 laparoscopic gastric sleeve (LGS) patients operated on average 22 months earlier. The biomarkers were fasting plasma level of pepsinogen I (PGI), pepsinogen II (PGII), PGI/PGII ratio, fasting and stimulated levels of amidated gastrin-17 (G17), and Helicobacter pylori antibodies (IgG). RESULTS: The prevalence of cases with abnormally low PGI (levels < 30 microg/L, seen typically in advanced atrophy of the gastric corpus mucosa, were 80 % and 40% in LGS and the LGBP groups, respectively (p = 0.013). Mean fasting G17 was normal, 3.1 +/- 4.3 pmol/L, in the LGBP patients but high, 13.9 +/- 17.2 pmol/L, in the LGS patients (p = 0.01), the levels exceeding the upper normal cut-off limit (7 pmol/L) in 40% of the LGS patients. The stimulated levels of G17 were normal (> 3 pmol/L after a protein rich drink) in all LGS patients, suggesting that the antral G cells functioned normally. CONCLUSIONS: Plasma PGI tends to be low in patients after bariatric surgery, in particular after LGS. "Sleeve" resection results in impairments in the secretory functions of the gastric corpus and fundus butleaves the antral functions intact.

Deficiency of the complex I of the mitochondrial respiratory chain but improved adenylate control over succinate-dependent respiration are human gastric cancer-specific phenomena.

The purpose of study was to comparatively characterize the oxidative phosphorylation (OXPHOS) and function of respiratory chain in mitochondria in human gastric corpus mucosa undergoing transition from normal to cancer states and in human gastric cancer cell lines, MKN28 and MKN45. The tissue samples taken by endobiopsy and the cells were permeabilized by saponin treatment to assess mitochondrial function in situ by high-resolution oxygraphy. Compared to the control group of endobiopsy samples, the maximal capacity of OXPHOS in the cancer group was almost twice lower. The respiratory chain complex I-dependent respiration, normalized to complex II-dependent respiration, was reduced that suggests deficiency of complex I, but the respiratory control by ADP in the presence of succinate was increased. Similar changes were observed also in mucosa adjacent to cancer tissue. The respiratory capacity of MKN45 cells was higher than that of MKN28 cells, but both types of cells exhibited a deficiency of complex I of the respiratory chain which appears to be an intrinsic property of the cancer cells. In conclusion, human gastric cancer is associated with decreased respiratory capacity, deficiency of the respiratory complex I of mitochondria, and improved coupling of succinate oxidation to phosphorylation in tumor tissue and adjacent atrophic mucosa. Detection of these changes in endobiopsy samples may be of diagnostic value.

Giant peptic ulcer hemorrhages: epidemiology, treatment, and outcome in the teaching hospital of Tartu.

UNLABELLED: The aim of the study was to analyze the management and outcome in the case of giant peptic ulcer hemorrhage (GPUH). MATERIAL AND METHODS: We analyzed the data of all 372 cases of 348 patients treated for acute peptic ulcer hemorrhage during 2005-2007. The source and intensity of hemorrhage was assessed endoscopically according to the Forrest classification: class I+II, persistent hemorrhage or signs of recent hemorrhage; and class III, ulcer without signs of recent hemorrhage. Of the 372 cases, 64 (17%) were GPUH (diameter, ≥2 cm) (group 1) and the remaining 308 (83%) were peptic ulcer hemorrhages of a standard size (SPUH) (diameter, <2 cm), which formed the control group (group 2). RESULTS: Forrest class I+II hemorrhage occurred significantly more frequently in the group 1 as compared with the group 2 (97% [62/64] vs. 77% [238/308]), as well as endoscopic hemostasis, (80% [51/64] vs. 57% [175/308]), repeat hemostasis procedures (22% [11/51] vs 6.3% [11/175]), and operative treatment (27.6% [16/58] vs 1.7% [5/290]) were needed more frequently in the group 1. No postoperative in-hospital deaths occurred in either group. Five patients died: 2 (3.4% [2/58]) in the group 1 and 3 (1.0% [3/290]) in the group 2. CONCLUSIONS: GPUHs were more intensive as compared with SPUHs and needed more endoscopic hemostasis, including repeat procedures and operative treatment. Endoscopic hemostasis and operative treatment allowed reducing mortality due to GPUH to 3.4%.

ß2-microglobulin, a novel biomarker of peripheral arterial disease, independently predicts aortic stiffness in these patients.

Arterial stiffness is a prominent feature of vascular ageing and strongly predicts cardiovascular and total mortality. The ß2-microglobulin, (ß2M) a newly identified biomarker of peripheral arterial disease (PAD), is related to renal insufficiency, inflammatory and neoplastic diseases, but may also play a role in vascular dysfunction. However, the relationship between arterial stiffness and ß2M has not been previously studied in patients with atherosclerosis. In the present study we examined a possible association between ß2M and arterial stiffness in patients with PAD and in healthy subjects. Plasma ß2M levels and parameters of arterial stiffness such as aortic pulse wave velocity (aPWV) and augmentation index (AIx) were measured in 66 patients with PAD and in 66 apparently healthy subjects. Plasma levels of ß2M, aPWV and AIx were significantly increased in patients with PAD compared with controls (1858.1 ± 472.8 vs 1554.5 ± 277.9 µg/L, p < 0.001; 9.9 ± 2.2 m/s vs 7.6 ± 1.6 m/s, p < 0.001; 28 ± 8 vs 14 ± 11%, p < 0.001; respectively). There existed significant correlation between aPWV and ß2M for the patient group (R = 0.47; p < 0.001), but not for the controls (R = 0.14; p = 0.26). In multivariate analysis, ß2M remained independently associated with aPWV, fetuin-A, age and glomerular filtration rate in patients (R(2) = 0.5, p < 0.001). We found no relationship between ß2M and AIx in either group. We demonstrated that among patients with PAD elevated plasma ß2M levels were associated with higher aortic stiffness irrespective of cardiovascular disease risk factors. These data suggest that ß2M may influence the pathogenesis of aortic stiffness in atherosclerosis.

Mitochondria and energetic depression in cell pathophysiology.

Mitochondrial dysfunction is a hallmark of almost all diseases. Acquired or inherited mutations of the mitochondrial genome DNA may give rise to mitochondrial diseases. Another class of disorders, in which mitochondrial impairments are initiated by extramitochondrial factors, includes neurodegenerative diseases and syndromes resulting from typical pathological processes, such as hypoxia/ischemia, inflammation, intoxications, and carcinogenesis. Both classes of diseases lead to cellular energetic depression (CED), which is characterized by decreased cytosolic phosphorylation potential that suppresses the cell's ability to do work and control the intracellular Ca(2+) homeostasis and its redox state. If progressing, CED leads to cell death, whose type is linked to the functional status of the mitochondria. In the case of limited deterioration, when some amounts of ATP can still be generated due to oxidative phosphorylation (OXPHOS), mitochondria launch the apoptotic cell death program by release of cytochrome c. Following pronounced CED, cytoplasmic ATP levels fall below the thresholds required for processing the ATP-dependent apoptotic cascade and the cell dies from necrosis. Both types of death can be grouped together as a mitochondrial cell death (MCD). However, there exist multiple adaptive reactions aimed at protecting cells against CED. In this context, a metabolic shift characterized by suppression of OXPHOS combined with activation of aerobic glycolysis as the main pathway for ATP synthesis (Warburg effect) is of central importance. Whereas this type of adaptation is sufficiently effective to avoid CED and to control the cellular redox state, thereby ensuring the cell survival, it also favors the avoidance of apoptotic cell death. This scenario may underlie uncontrolled cellular proliferation and growth, eventually resulting in carcinogenesis.

Atrophic gastritis: deficient complex I of the respiratory chain in the mitochondria of corpus mucosal cells.

BACKGROUND: Mitochondrial dysfunction is one of the most characteristic properties of the cancer cell. However, it is not known whether oxidative energy metabolism has already become altered in conditions of atrophic gastritis, a precancerous state of gastric disease. The purpose of our study was to comparatively characterize oxidative phosphorylation (OXPHOS) in the atrophic and nonatrophic gastric corpus mucosa. METHODS: Mucosal biopsies were taken from 12 patients with corpus dominant atrophic gastritis and from 12 patients with nonatrophic mucosa (controls). One part of the tissue samples was permeabilized with saponin for analysis of the function of the respiratory chain using high-resolution respirometry, and another part was used for histopathological examination. The serum level of pepsinogen I (S-PGI) was determined with a specific enzyme immunoassay (EIA). RESULTS: Compared to the control group, the maximal capacity of OXPHOS in the atrophy group was almost twofold lower, the respiratory chain complex I-dependent respiration, normalized to complex II-dependent respiration, was reduced, and respiratory control by ADP in the presence of succinate was increased in the atrophic corpus mucosa. In the whole cohort of the patients studied, serum S-PGI level correlated positively with complex I-dependent respiration or complex I-dependent to complex II-dependent respiration ratio. CONCLUSIONS: Corpus dominant atrophic gastritis is characterized by decreased respiratory capacity and relative deficiency of the respiratory complex I of mitochondria in the mucosa, the latter defect probably limiting mitochondrial ATP production and energetic support of the secretory function of the zymogenic mucosal cells.

Persistence of Helicobacter pylori infection in patients with peptic ulcer perforation.

OBJECTIVE: In patients with perforated peptic ulcer (PPU) the convergence between the high eradication rate of Helicobacter pylori infection and low rates of ulcer relapse after treatment has been associated with reinfection by non-virulent strains. The objective of this study was to evaluate the persistence of infection by virulent H. pylori strains and ulcer recurrence in 33 patients with PPU one year after surgery and antimicrobial treatment. MATERIAL AND METHODS: The histological evaluation and molecular detection of H. pylori cagA and ureA genes, vacA allelic types and the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses of the glmM gene products from antral mucosa specimens were performed initially, 2-5 months and 1 year after therapy. RESULTS: The density of H. pylori colonization was temporarily decreased (p<0.05) 2-5 months after therapy. After one year, complete eradication was achieved in only 7 patients (23%) at histological examination and recurrent ulcers were found in 3/33 (9%) patients. The vacA s1a allelic type of cagA-positive strains persisted in 19/33 (58%) PPU patients with identical PCR-RFLP fingerprints in 8/9 (89%) of the patients. CONCLUSIONS: In PPU patients with a low eradication rate of H. pylori infection after surgical and antimicrobial treatment, the frequent recrudescence of the infection is mostly caused by the persisting virulent strains of the cagA and vacA s1a subtypes. In the 1-year follow-up period the recurrent ulceration can be postponed just by the lowered colonization density of H. pylori after eradicative therapy.

Successful rescue therapy with mycophenolate mofetil in kidney transplantation improves the long-term graft survival.

OBJECTIVE: The aim of this study was to compare the graft survival after kidney transplantation in patients treated with azathioprine (AZA) or mycophenolate mofetil (MMF) and analyze the significance of different risk factors for graft survival. MATERIAL AND METHODS: A total of 137 patients, transplanted between January 1996 and June 2001, were retrospectively divided into two groups: patients who received AZA together with cyclosporine A and methylprednisolone (AZA group, n=72) and patients who received MMF either immediately or were switched from AZA to MMF during 3 months (MMF group, n=65). RESULTS: According to Kaplan-Meier analysis, a 1-year graft survival was 79% in the AZA group and 85% in the MMF group; a 6-year graft survival was 51% and 67%, respectively (P=0.046). Multivariate Cox survival model demonstrated that MMF therapy reduced the risk of graft loss by 34% (P=0.028), while delayed graft function increased the risk of graft loss (risk ratio 2.26, P=0.009). A statistically significant difference in total cholesterol level (6.7 vs. 5.7 mmol/L, respectively; P=0.002), mean systolic blood pressure (145 vs. 134 mmHg, P=0.009), and cyclosporine A daily dose (238 vs. 203 mg, P=0.015) between the AZA and MMF groups at 1 year was revealed. CONCLUSION: MMF rescue therapy improves the long-term graft survival compared to AZA despite high early rejection rate and avoids the negative impact of acute rejections on graft survival.

Oxidative phosphorylation and its coupling to mitochondrial creatine and adenylate kinases in human gastric mucosa.

Energy metabolism in gastrobiopsy specimens of the antral and corpus mucosa, treated with saponin to permeabilize the cells, was studied in patients with gastric diseases. The results show twice lower oxidative capacity in the antral mucosa than in the corpus mucosa and the relative deficiency of antral mitochondria in complex I. The mucosal cells expressed mitochondrial and cytosolic isoforms of creatine kinase and adenylate kinase (AK). Creatine (20 mM) and AMP (2 mM) markedly stimulated mitochondrial respiration in the presence of submaximal ADP or ATP concentrations, and creatine reduced apparent Km for ADP in stimulation of respiration, which indicates the functional coupling of mitochondrial kinases to oxidative phosphorylation. Addition of exogenous cytochrome c increased ADP-dependent respiration, and the large-scale cytochrome c effect (>or=20%) was associated with suppressed stimulation of respiration by creatine and AMP in the mucosal preparations. These results point to the impaired mitochondrial outer membrane, probably attributed to the pathogenic effects of Helicobacter pylori. Compared with the corpus mucosa, the antral mucosa exhibited greater sensitivity to such type of injury as the prevalence of the large-scale cytochrome c effect was twice higher among the latter specimens. Active chronic gastritis was associated with decreased respiratory capacity of the corpus mucosa but with its increase in the antral mucosa. In conclusion, human gastric mucosal cells express the mitochondrial and cytosolic isoforms of CK and AK participating in intracellular energy transfer systems. Gastric mucosa disease is associated with the altered functions of these systems and oxidative phosphorylation.

Changes in the histology and function of gastric mucosa and in Helicobacter pylori colonization during a long-term follow-up period after vagotomy in duodenal ulcer patients.

BACKGROUND/AIMS: To investigate changes in the histology and the Helicobacter pylori (H. pylori) prevalence and density of the gastric mucosa, as well as in fasting serum gastrin and serum pepsinogen I, depending on completeness of vagotomy, and in cases of recurrent ulcer, during 14 years after operation in duodenal ulcer patients. METHODOLOGY: 122 vagotomized duodenal ulcer patients were studied twice on average 9 and 14 years after operation. The presence of recurrent ulcer and completeness of vagotomy were assessed simultaneously endoscopically and by endoscopic Congo red test. The histology of the gastric antrum and corpus mucosa was assessed in accordance with the Sydney system. The amount of H. pylori in the specimens was detected by microscopic counting; gastrin and pepsinogen I in serum were determined radioimmunologically. RESULTS: During the 14-year follow-up period, complete vagotomy patients were characterized by a smaller amount of active antrum gastritis and a larger amount of active chronic corpus gastritis involving corpus atrophy in 46% of cases 14 years after operation. Recurrent ulcer patients were characterized by a significantly higher prevalence of high-grade H. pylori colonization and active mucosal inflammation in the antrum as well as by a lower level of active mucosal inflammation and atrophy in the corpus and a higher serum pepsinogen I level compared with complete vagotomy cases. The data of incomplete vagotomy patients without recurrent ulcer became more similar to those recorded for recurrent ulcer patients. CONCLUSIONS: In duodenal ulcer patients, changes in the histology of the gastric antrum and corpus mucosa as well as in H. pylori prevalence and density and in serum pepsinogen I levels are different depending on completeness of vagotomy during 14 years after operation.

Regional differences in semen qualities in the Baltic region.

Recent prospective studies of male reproductive health have shown differences between several European countries. Our objective was to evaluate the current situation in the two Baltic States Estonia and Lithuania. In 1997-99 we investigated semen parameters, levels of reproductive hormones and general health factors of 196 men from the general population in Lithuania; from Estonia, 79 men from the general population and 118 soldiers were investigated. Adjusted for interlaboratory differences and abstinence period, sperm concentration of Lithuanian and Estonian men from the general populations were shown to be 55 and 67 million/mL, respectively. The Estonian soldiers had the highest sperm concentration, 82 million/mL. The frequencies of morphologically normal spermatozoa were 6.2, 7.7 and 9.6%, respectively. In contrast to the semen qualities, highest Inhibin B levels were detected in the Lithuanians (233 pg/mL) followed by Estonian men from the general population (220 pg/mL) and Estonian soldiers (185 pg/mL). The soldiers had also the lowest level of testosterone and oestradiol. The sperm counts of the Estonian and Lithuanian men investigated here are higher than recently shown for Norwegian, Danish, Estonian and Finnish men. Comparisons should be cautiously drawn as the groups are not completely comparable. Still, even within the Baltic region, geographically close and sharing common recent social history, differences in semen quality and levels of reproductive hormones are apparent.

Association of cagA and vacA genotypes of Helicobacter pylori with gastric diseases in Estonia.

Gastric biopsy specimens from 156 adult patients from southern Estonia suffering from chronic gastritis, peptic ulcer disease, and perforated peptic ulcer were analyzed by PCR. The cagA gene was evenly distributed throughout 87% of the specimens from the patients with the different gastric diseases. The presence of the cagA gene correlated with that of vacA signal sequence type s1a (99%). However, no clear differences were found in the distribution of cagA and vacA genotypes among patients in Estonia with severe perforated peptic ulcer, uncomplicated peptic ulcer, or chronic gastritis.