Pepsinogen test for the evaluation of precancerous changes in gastric mucosa: a population-based study.

AIMS: The aim of the study was to evaluate the rationale of blood pepsinogen (PG) testing in population based screening settings. METHODS: Participants from a cross-sectional population-based study of cardiovascular risk factors in Latvia were invited to participate in the current study. Pepsinogen I and II were measured in blood samples taken during the initial study and at follow-up; upper gastrointestinal endoscopy was performed. There were three groups of patients: with moderately decreased (PG I< 70 ng/ml and PG I/PG II ratio < 3), with strongly decreased (PG I< 30 ng/ml and PG I/PG II ratio < 2), and with normal PG level. Biopsy with H. pylori detection was performed (updated Sydney system). RESULTS: Results from 259 patients were analyzed. Pepsinogens were decreased in 133 (51.4%), H. pylori was positive in 177 (66.0%) cases. Mean age was significantly lower in patients with normal compared to strongly decreased PG level group (52.8 vs. 64.1 years, p<0.001). Prevalence of severe corpus atrophy was higher in the strongly decreased compared to the normal PG test group: 7.0% vs. 0%; the same tendency was noted in the distribution of OLGA stages III-IV - 10.5% and 0.0%, OLGIM stages III-IV - 3.5% and 0%, and low-grade dysplasia - 15.8% and 2.4% (p<0.05). Two cases of gastric cancer were found; both presented decreased PG levels. A strong association between H. pylori eradication and PG ratio dynamics was found (p<0.05). CONCLUSIONS: All high-risk lesions were found in the decreased PG test groups; two cancer cases were revealed. However, PG demonstrated low specificity and low value of repeated testing. The value of PG as a sole test for gastric cancer risk is limited.

Prevalence estimation of celiac disease in the general adult population of Latvia using serology and HLA genotyping.

BACKGROUND: Prevalence estimates for celiac disease (CD) depend on the method used. The role of deamidated gliadin peptide (DGP) and genetic testing in epidemiological studies and diagnostic settings of celiac disease (CD) has still to be established. OBJECTIVES: The objective of this article is to assess the prevalence of CD in Latvia by combining serological tests with DQ2.5/DQ8 testing. METHODS: A total of 1444 adults from a randomly selected cross-sectional general population sample were tested by ELISA for tTG IgA, DGP IgA and IgG antibodies (QUANTA Lite®, Inova Diagnostics Inc). Samples with tTG IgA ≥20U were tested for EMA IgA by indirect immunofluorescence assay, and all specimens with tTG IgA ≥15U were tested by QUANTA-Flash® chemiluminescent assays (CIA) (Inova Diagnostics Inc) for tTG IgA, DGP IgA and IgG. DQ2.5/8 was detected in individuals with any positive ELISA test and a subgroup of controls. RESULTS: Forty-three individuals (2.98%; 95% CI: 2.10-3.86%) tested positive by at least one ELISA test; 41.86% of the serology-positive individuals (any test above the cutoff) were DQ positive. Six individuals (0.42%; 95% CI: 0.09-0.75%) were triple ELISA positive, and DQ2.5 or DQ8 was positive in all; 0.35% (95% CI: 0.05-0.65%) were tTG IgA and EMA positive. Two tTG IgA-negative cases were both DGP IgG and IgA positive, both being DQ positive; including them in the "serology-positive" group would increase the prevalence to 0.49% (95% CI: 0.13-0.85%). CIA tests revealed 2 tTG IgA-positive and EMA-negative cases with a positive genotype. DQ2.5 or DQ8 genotype was positive in 28.6% of the serology-negative population. CONCLUSIONS: Estimates of the prevalence of CD in Latvia based on the serogenetic testing approach range from 0.35% to 0.49% depending on the criteria used. There is a rationale for combining serological tests and DQ2.5/8 genotyping.

Prevalence of Helicobacter pylori infection and atrophic gastritis in Latvia.

OBJECTIVES: Helicobacter pylori infection and atrophic gastritis are related to an increased risk for gastric cancer. There is a decrease in global H. pylori prevalence. We analyzed the prevalence of H. pylori infection in Latvia by the plasma IgG test and the presence of atrophy by means of pepsinogen testing. METHODS: This subanalysis was carried out on a randomly selected cross-sectional sample of a general population of adults to access cardiovascular risk factors. Plasma samples were screened for H. pylori IgG (cutoff value 24 U/ml), and pepsinogens (Pg) I and II. Pg cutoff values of PgI/PgII ≤ 3 and PgI ≤ 70 ng/ml were used to assess the prevalence of atrophy of any grade and PgI/PgII ≤ 2 and PgI ≤ 30 ng/ml for advanced atrophy. RESULTS: Altogether, 3564 serum samples were available for the study (2346 women, 1218 men; median age 54 years). Of the tested individuals, 79.21% were H. pylori positive, with no difference between sexes. The prevalence increased with age (P<0.001). Atrophy of any grade was identified in 1444 individuals (40.52%) and advanced atrophy in 475 individuals (13.33%). Linear association with age was present in both response types (P<0.001). The prevalence of atrophy of any grade was higher in women (41.73%) than in men (38.18%; P=0.04); this difference was lost for advanced atrophy (women 13.98%, men 12.07%; P=0.1). CONCLUSION: The prevalence of H. pylori infection or atrophy remains high in Latvia. Determining the right cutoff value is critically important for pepsinogen-based atrophy detection in Europe in order to objectively stratify gastric cancer risk.