Helicobacter pylori infection and low serum pepsinogen I level as risk factors for gastric carcinoma

AIM: To study whether examination of CagA antibodies could increase the odds ratio for gastric cancer in a casecontrol study, and how often other serum markers of gastric cancer risk could be found in Helicobacter pylorinegative patients.METHODS: H pylori CagA and parietal cell antibodies(PCAs), and serum pepsinogen Ⅰ (SPGI) levels were compared between patients with gastric cancer and controls who received endoscopic examination due to reasons other than gastrointestinal malignancy.RESULTS: The odds ratio (OR) for gastric cancer was2.9 (95% CI 1.4-5.8) in H pylori+ patients, and 2.4 (95%CI 1.2-4.9) in CagA+ patients. When results of H pylori and CagA antibodies were combined, OR increased to5.0 (95% CI 2.5-10.0). Furthermore, if cardia cancer patients were excluded, the OR increased to 6.8 (95% CI3.1-14.8). Among patients with a low SPGI level, the OR was 12.0 (95% CI 4.1-35.3). However, the risk was significant only in the older age group. The number of patients with low SPGI was significantly higher in H pylori-/CagA+ patients as compared to other cancer patients.CONCLUSION: Examination of both H pylori and CagA antibodies increases the OR for gastric cancer in our casecontrol study. CagA antibodies are important in detecting previous H pylori infection in advanced atrophic gastritis or cancer when spontaneous decline of H pylori antibodies occurs. SPGI may be helpful in screening elderly gastric cancer patients.

Milk protein IgG and IgA:The association with milk-induced gastrointestinal symptoms in adults

AIM:To study the association between serum levels of milk protein IgG and IgA antibodies and milk-related gastrointestinal symptoms in adults.METHODS:Milk protein IgG and IgA antibodies were determined in serum samples of 400 subjects from five outpatient clinics in Southern Finland.Subjects were randomly selected from a total of 1900 adults undergoing laboratory investigations in primary care.All 400 participants had completed a questionnaire on abdominal symptoms and dairy consumption while waiting for the laboratory visit.The questionnaire covered the nature and frequency of gastrointestinal problems,the provoking food items,family history and allergies.Twelve serum samples were disqualifi ed due to insuff icient amount of sera.The levels of specif ic milk protein IgG and IgA were measured by using the ELISA technique.The association of the milk protein-specific antibody level was studied in relation to the milk-related gastrointestinal symptoms and dairy consumption.RESULTS:Subjects drinking milk(n=265) had higher levels of milk protein IgG in their sera than non-milk drinkers(n=123,P<0.001).Subjects with gastrointestinal problems related to milk drinking(n=119) consumed less milk but had higher milk protein IgG levels than those with no milk-related gastrointestinal symptoms(n=198,P=0.02).Among the symptomatic subjects,those reporting dyspeptic symptoms had lower milk protein IgG levels than non-dyspeptics(P<0.05).However,dyspepsia was not associated with milk drinking(P=0.5).The association of high milk protein IgG levels with constipation was close to the level of statistical signif icance.Diarrhea had no association with milk protein IgG level(P=0.5).With regard to minor symptoms,flatulence and bloating(P=0.8),were not associated with milk protein IgG level.Milk protein IgA levels did not show any association with milk drinking or abdominal symptoms.The levels of milk protein IgA and IgG declined as the age of the subjects increased(P<0.004).CONCLUSION:Milk protein IgG but not milk IgA seems to be associated with self-reported milk-induced gastrointestinal symptoms.

Association of Helicobacter pylori IgA antibodies with the risk of peptic ulcer disease and gastric cancer

AIM: To compare the prevalence of Helicobacter pylori (Hpylori) IgG and IgA antibodies between adult subjects,with defined gastric diseases, nondefined gastric disorders and those representing the population.METHODS: Data on H pylori IgG and IgA antibodies,determined by enzyme immunoassay, were analyzed in 3 252 subjects with DGD including 482 patients with gastric ulcer, 882 patients with duodenal ulcer, 1 525patients with chronic gastritis only and 363 subjects with subsequent gastric cancer, 19 145 patients with NoDg and4 854 POPUL subjects. The age-adjusted prevalences were calculated for 1- and 20-year age cohorts.RESULTS: The prevalences of IgG antibodies were equally high (89-96%) in all 20-year age cohorts of the DGD groups, whereas the prevalences of IgG antibodies were lower and increased by age in the POPUL and NoDg groups. The prevalences of IgA antibodies were also higher in the DGD groups; among them CA (84-89%) and GU groups (78-91%) showed significantly higher prevalences than DU (68-77%) and CG patients (59-74%) (OR 2.49, 95%CI 1.86-3.34 between the GU and DU groups). In the CA, GU, and DU groups, the IgA prevalences showed only minor variation according to age, while they increased by age in the CG, POPUL, and NoDg groups (P≤0.0001). The IgA response, but not the IgG response, was associated with an increased risk of CA (OR 2.41, 95%CI 1.79-3.53) and GU (OR 2.57,95%CI 1.95-3.39) in comparison with CG patients.CONCLUSION: An IgA antibody response during H pylori infection is significantly more common in CA and GU patients as compared with CG patients.

Stool antigen tests in the diagnosis of Helicobacter pylori infection before and after eradication therapy

Aim: To evaluate two enzyme immunoassay-based stool antigen tests, Premier Platinum HpSA and Amplified IDEIA HpStAR, and one rapid test, ImmunoCard STAT! HpSA, in the primary diagnosis of Helicobacter pylori (H pylori) infection and after eradication therapy.METHODS: Altogether 1 574 adult subjects were screened with a whole-blood H pylori antibody test and positive results were confirmed with locally validated serology and 13C-urea breath test. All 185 subjects,confirmed to be H pylori positive, and 97 H pylorinegative individuals, randomly selected from the screened study population and with negative results in serology and UBT, were enrolled. After eradication therapy the results of 182 subjects were assessed.RESULTS: At baseline, the sensitivity of HpSA and HpStAR was 91.9% and 96.2%, respectively, and specificity was 95.9% for both tests. ImmunoCard had sensitivity of 93.0% but specificity of only 88.7%. After eradication therapy, HpSA and HpStAR had sernsitivity of 81.3% and 100%, and specificity of 97.0% and 97.6%,respectively. ImmunoCard had sensitivity of 93.8% and specificity of 97.0%. HpSA, HpStAR, and ImmunoCard had PPV 77%, 80%, and 75%, and NPV 98%, 100%,and 99%, respectively.CONCLUSION: In primary diagnosis, the EIA-based tests performed well. After eradication therapy, negative results were highly accurate for all the three tests.HpStAR had the best overall performance.