Marco Ruina

Evaluation of a new enzyme immunoassay for detecting Helicobacter pylori in feces : a prospective pilot study

OBJECTIVES:There is an increasing interest in noninvasive tests for detecting Helicobacter pylori (H. pylori) infection. Unlike serological and urea breath tests, the possibility of searching for H. pylori in feces has been scarcely investigated. The aim of this prospective pilot study was to evaluate the usefulness of a new enzyme immunoassay for detecting H. pylori antigens in feces, as a predictor of H. pylori status in the pre- and posttreatment settings.METHODS:One hundred and fifty-four symptomatic, anti-H. pylori untreated patients (Group A) and 116 anti-H. pylori treated patients (Group B) underwent gastroscopy with biopsies of the antrum and corpus for histology (H) and rapid urease test (RUT). In the anti-H. pylori treated group, a 13C-urea breath test (UBT) was also performed. In Group A, H. pylori status was defined as positive or negative when both H and RUT gave concordant positive or negative results. In Group B, the patients were considered eradicated if all three tests were negative. A stool specimen was collected from all patients the day after gastroscopy, and tested by using an enzyme immunoassay commercial kit for detecting H. pylori antigens in feces (HpSAT).RESULTS:Eighty-five patients in Group A (55%) and 44 in Group B (38%) were H. pylori infected. On the whole, HpSAT showed a sensitivity of 94% and specificity of 86%. In Group A and Group B, sensitivity and specificity were 94%versus 93%, and 90%versus 82%, respectively (p < 0.05).CONCLUSIONS:HpSAT seems to be a reliable method for predicting H. pylori status in anti-H. pylori untreated patients. Conversely, the test appears less suitable to evaluate the outcome of the eradicating treatment. Consequently, it is likely to be accepted for the primary diagnosis of H. pylori status, particularly in dyspeptic young patients.

Helicobacter pylori and chronic bronchitis.

BACKGROUNDnChronic infections such as those caused by Helicobacter pylori, Chlamydia pneumoniae, and cytomegalovirus have been epidemiologically related to coronary heart disease (CHD). Other studies place H. pylori in relation to other extradigestive diseases. We carried out an epidemiologic pilot study to evaluate the prevalence of H. pylori in patients with chronic bronchitis, a respiratory disease characterized by persistent chronic inflammation, in comparison with a matched control group.nnnMETHODSnAn enzyme-linked immunosorbent assay IgG test for H. pylori diagnosis was performed in 60 consecutive patients with chronic bronchitis (15 women and 45 men; age range, 50-89 years; mean age, 70.38 years) and in 69 control subjects, well matched for age and social status (19 women and 50 men: age range, 52-90 years; mean age, 71.3 years).nnnRESULTSnFoty-nine of 60 patients with chronic bronchitis (81.6%) and 40 of 69 subjects in the control group (57.9%) were H. pylori-positive (P = 0.0079). The odds ratio, calculated by simple analysis (3.2) and confirmed by logistic regression analysis (3.399), indicated that H. pylori infection greatly increases the risk of chronic bronchitis.nnnCONCLUSIONSnTo date, CHD is the only convincing association between H. pylori infection and an extradigestive disease. The main conclusion of this pilot study is that H. pylori infection seems to increase the risk of developing of chronic bronchitis. An important step in this field will be to evaluate the possible change in the clinical conditions after successful eradication therapy in H. pylori-positive patients with chronic bronchitis.

Short-term low-dose triple therapy with azithromycin, metronidazole and lansoprazole appears highly effective for the eradication of Helicobacter pylori

Background: Although the OCN (omeprazole, clarithromycin and nitroimidazoles) shortterm low‐dose regimens are regarded as ‘the standard’ in the treatment of Helicobacter pylori infection, azithromycin is a new‐generation, acid‐stable macrolide which may prove particularly useful for a new short‐term low‐dose triple therapy regimen. Objective: To further improve OCN eradication treatments by reducing both the number of pills and the total cost. Methods: A new short‐term low‐dose triple therapy (LAM) using lansoprazole 30mg once a day for 1 week, azithromycin 500 mg once a day for 3 days, and metronidazole 250mg twice a day for the same 3 days, was administrated to 60 patients presenting with H. pylori‐positive gastritis with or without peptic ulcer, and compared with the classic ‘Bazzoli regimen’ (OCT: omeprazole, clarithromycin, tinidazole) in 60 matched patients. H. pylori infection before and after therapy was evaluated by a rapid urease test, conventional histology and toluidine‐stained semi‐thin sections. Three biopsies from the corpus and three from the antrum were taken during endoscopical examination before and 7‐8 weeks after discontinuation of the treatment. Patient compliance, drug tolerance and drug costs were also taken into consideration. Results: H. pylori infection was eradicated 7‐8 weeks after treatment in 56 of the 60 patients in the LAM group (93.3%), and in 52 of the 57 patients in the OCT group who completed the treatment (91.2%), with no statistical difference. When gastric or duodenal ulceration was present, ulcer healing was observed in all cases. Conclusion: The new proposed short‐term low‐dose triple therapy (LAM) appears to be as effective as the OCT for the eradication of H. pylori infection. The new treatment, however, seems to have advantages in terms of drug tolerance, patient compliance and therapy cost.

Helicobacter pylori stool antigen test: clinical evaluation and cost analysis of a new enzyme immunoassay.

Noninvasive tests for Helicobacter pylori areincreasingly used. Recently, an enzyme immunoassay forH. pylori detection in feces has been put on the market.Aim of this multicenter study was to evaluate the usefulness of this novel test as apredictor of H. pylori status in the pretreatmentsetting. Three hundred consecutive patients wereenrolled. None of the patients had received anyeradicating treatment in the last 12 months, and all underwentgastroscopy with biopsies of the antrum and body forhistology (H) and rapid urease test (RUT). H. pyloristatus was defined positive (or negative) if both H and RUT were positive (or negative). When H and RUTgave conflicting results, the patients were classifiedas H. pylori indeterminate. A stool specimen wascollected for each patient and tested by using a novel enzyme immunoassay for H. pylori detection(HpSAT). Sensitivity, specificity, and diagnosticaccuracy of the test were calculated, as was the cost ofeach assay. H. pylori status was positive in 159patients, negative in 131, and indeterminate in 10. HpSATgave evaluable results (positive or negative) in 293patients, and doubtful results in 7 (2.3%). Sensitivity,specificity, and diagnostic accuracy of HpSAT were 96.8%, 89.7%, and 93.6% respectively.Considering the H. pylori-indeterminate patients aspositive, the percentages were 95.8%, 98.7%, and 93.2%respectively. The cost for each assay was about US

Evaluation of a new rapid immunoassay for the detection of Helicobacter pylori in faeces: a prospective pilot study

27. These results suggest that HpSAT is anoninvasive, simple, reliable, fast, and cheap methodfor evaluating H. pylori status in the pretreatmentsetting.

A Four-Day Low Dose Triple Therapy Regimen for the Treatment of Helicobacter pylori Infection

Background :u2002Detection of Helicobacter pylori antigen in faeces is a valid method to diagnose H. pylori infection. Presently available stool tests are performed in the laboratory, and diagnostic report is delayed.

Touch Cytology (A Reliable and Cost-Effective Method for Diagnosis of Helicobacter pylori Infection)

Objective:The current guidelines recommend 1-wk triple therapy regimens for eradicating H. pylori infection. Until now, shorter regimens have scarcely been investigated. Azithromycin is a new generation macrolide antibiotic with unusual and favorable pharmacokinetics, and seems to be a very promising agent for innovative anti-H. pylori regimens. We assessed the efficacy and tolerability of a new 4-day low dose triple therapy in comparison with a well established 1-wk triple therapy in the treatment of Helicobacter pylori infection.Methods:One hundred-sixty consecutive patients with biopsy-proven H. pylori infection were randomized to receive lansoprazole 30 mg b.i.d. on days 1–4, azithromycin 500 mg u.i. on days 2–4, and tinidazole 2000 mg u.i.d. on day 3 (LAT group), or 7 days of triple therapy of omeprazole 20 mg u.i.d. clarithromycin 250 mg b.i.d., and tinidazole 500 mg b.i.d. (OCT group). Patients with gastric or duodenal active ulcer received proton pump inhibitors for an additional 4 wk. H. pylori eradication was defined as negative of both rapid urease test and histology on biopsies taken from the gastric body and antrum at least 1 month after the end of treatment.Results:Seven patients in the LAT group and four in the OCT group were lost to follow-up. No significant difference in either efficacy or tolerability was observed between the two regimens. Active ulcers healed in 97.8% of cases with LAT and in 100% of cases with OCT. The eradication rate was 80.8% in the LAT group and 85.5% in the OCT group, considering the per-protocol results, and 73.3% and 81.2%, respectively, considering the intention-to-treat results. Side effects occurred in one LAzT patient and in two OCT patients; they were mild and did not interfere with compliance.Conclusion:The new proposed ultrashort triple therapy, including lansoprazole, low dose azithromycin for 3 days, and a single dose of tinidazole, appears to be a very effective anti-H. pylori regimen, a simpler, cheaper, well-tolerated, and equally effective alternative to 1-wk triple therapy.

Histologic findings and Helicobacter pylori in duodenal biopsies

A variety of reliable methods are available fordetecting Helicobacter pylori (Hp) during uppergastrointestinal endoscopy. We evaluated the clinicalutility and cost-effectiveness of rapid urease test (RUT), touch cytology (TC), and histology (H).Two hundred thirty-eight consecutive patients (178without previous medical treatment and 60 formerlytreated with anti-Hp therapy) were tested for Hpinfection by RUT, TC, and H (H&E stain). Theinfection status for each patient was established by aconcordance of two test results. The time to carry outthe three tests and their cost were also calculated. Sensitivity of TC (100%) was significantlyhigher than that of RUT (86.8%; P < 0.001), but notthan that of H (94.9%). RUT was significantly morespecific than H (100% vs 95.6%; P < 0.05), but not than TC (96.4%). Hp infection was more frequentin the patients with chronic active gastritis than inthose with chronic nonactive gastritis (P < 0.001).No Hp infection was detected in absence of chronic antral inflammation. RUT resulted the cheapestmethod and H the most expensive; TC is faster andcheaper than H. When additional information about theseverity of mucosal damage or the presence of cell atypias is not necessary, histologicexamination can be omitted, and a cost-effectivestrategy for assessing Hp status might consist in takingtwo antral biopsies, the former for performing RUT andthe latter for preparing a slide by TC, whichshould be stained and examined only when the RUT resultis negative.

Histological findings in gastric mucosa in patients treated with non-steroidal anti-inflammatory drugs.

We have studied the morphologic aspects of the duodenal bulb in relation to Helicobacter pylori infection in a large group of patients with endoscopically assessed duodenitis to learn more about the pathogenesis of nonspecific duodenitis (bulbitis) and to clarify the specific role of H. pylori. Eight duodenal biopsy specimens in the four quadrants of the first part of the bulb and four gastric antral biopsy specimens were taken in 208 patients. Specimens were fixed in formalin, or in glutaraldehyde, then slides were stained with hematoxylin and eosin, periodic acid-Schiff, and Alcian-Giemsa, and with toluidine blue for semithin sections. Duodenal histology revealed inflammation in 155 (74.5%) and H. pylori-like bacterial bodies in 153 (73.5%) of the patients; H. pylori infection in the gastric antrum was diagnosed in 173 (83.1%) of the patients. Distinguishing histologic aspects appeared to be related to the presence of H. pylori infection. We believe that the present histologic grading of duodenitis correlates better with the natural history of H. pylori infection in the duodenal bulb, and better fits the requirements of a modern classification than the classification commonly used in duodenitis. We conclude that the term H. pylori-linked bulbitis should be adopted as the proper term to identify the particular kind of duodenitis predisposing to peptic ulcer.

Ultrastructural patterns of Helicobacter pylori.

AIMS--To identify distinguishing and general histological features related to the use of non-steroidal anti-inflammatory drugs (NSAID). METHODS--Slides from gastric antral biopsies of 50 patients with osteoarthritis taking NSAID were compared with slides from antral biopsies of 50 control cases matched for age, sex, and race. Semithin sections stained with toluidine blue were used. RESULTS--Chronic gastritis was seen in 76% of the patients taking NSAID and in 58% of the control cases; active inflammation was detected in 10% of the NSAID treated patients and in 24% of the control cases, and it appeared closely related with Helicobacter pylori infection. Some histological features common to all slides of patients taking NSAID were recognised. These consisted of focal erosions of the gastric epithelium and macroerosions, and they seemed to represent successive steps of a process of desquamation. CONCLUSIONS--Some distinguishing morphological aspects appeared prominent; it is suggested that these may be related to the pathogenesis of NSAID linked peptic ulceration. On the other hand, epithelial damage due to NSAID appears very different from that due to Helicobacter pylori, another important factor involved in the aetiopathogenesis of peptic disease.