The serological diagnosis of human hydatid disease by time-resolved fluoroimmunoassay.

The use of a new immunoassay, time-resolved fluoroimmunoassay (TR-FIA), in the diagnosis of human hydatid disease has been evaluated. This technique, which is based on the labelling of antibodies with europium (Eu), was compared with a well-established method, the enzyme linked immunosorbent assay (ELISA). Of 102 patients with hydatid disease, 97 (95.1%) were positive according to TR-FIA and 83 (81.4%) according to ELISA. The rate of non-specificity for other parasitic infections (n = 206) was 8.7% for TR-FIA and 17.5% for ELISA. It is concluded that TR-FIA is more sensitive and more specific than ELISA in the diagnosis of human hydatid disease.

Anti-TNF-alpha antibodies are not associated with Helicobacter pylori induced gastritis.

Over the past few years, it has been suggested that increased gastric production of some cytokines, including tumor factor-alpha (TNF-alpha), play a crucial role in the pathogenesis of H. pylori associated gastroduodenal diseases. On the other hand, it has been postulated that the presence of autoantibodies directed against several cytokines could represent or a down-regulatory response of the host to limit the damage associated with chronic bacterial infection or a specific cytokine inhibitor. The aim of this study was to evaluate whether serum anti-TNF-alpha antibodies are produced in response to H. pylori infection. The anti-TNF-alpha antibody titer among H. pylori positive and H. pylori negative patients showed no statistically significant difference. Interestingly, after eradication of H. pylori, no significant modification in anti-TNF-alpha antibody levels was found. In H. pylori positive patients, no correlations (either positive or negative) was demonstrated between anti-TNF-alpha antibody and activity of gastritis, nor between these antibodies levels and presence of duodenal ulcer. The lack of correlation between anti-TNF-alpha antibody levels and activity of gastritis indicates that these autoantibodies do not affect the clinical course of the H. pylori associated gastroduodenal diseases. Therefore, the biological and clinical relevance (if any) of anti-TNF-alpha antibodies in H. pylori associated gastritis remains to be better elucidated.

Improvement of intestinal metaplasia six month after misoprostol treatment.

PURPOSE: To establish whether misoprostol (a synthetic prostanoid) is effective in improving intestinal metaplasia of dyspeptic patients. PATIENTS: Of the 206 dyspeptic patients without Helicobacter pylori, 18 (7.1%) had histological evidence of intestinal metaplasia (2 presented mild metaplasia, 9 moderate and 7 severe). They were treated with misoprostol 200 mg twice daily for six months and, after stopping the treatment, they all underwent endoscopic control. RESULTS: There was a statistical significant improvement of intestinal metaplasia (p < 0.001) and of the activity of antral gastritis (p = 0.03). There were no significant changes in antral and body specimens during follow-up. DISCUSSION: Though the small number of the patients and the lack of control group, our results suggest that misoprostol allows regression and/or improvement of histological IM (p < 0.001). It has proved to be effective in prevention of both gastric and duodenal ulcers induced by NSAID therapy, probably related largely to replacement of endogenous prostaglandins inhibited by the use of NSAID and it may also exerts its protective effects through inhibition of gastric acid secretion. Moreover, misoprostol showed to increase the rate of gastric blood flow, inducing a mucosal protective effect against the factors damaging gastric mucosa. It has been also documented that misoprostol regulates inflammatory cytokines and prolonged the survival of transplants, reflecting both its immunosuppressive and anti-inflammatory effect. In conclusion, since intestinal metaplasia increases the risk of gastric cancer, the use of misoprostol, in this pathology, would be of some interest.

[Effects of the triple therapy in the eradication of Helicobacter pylori: comparison of 3 different antibiotics]. / Effetti della tripla terapia nell'eradicazione dell'Helicobacter pylori: confronto tra tre diversi antibiotici.

To compare the effectiveness, in eradicating Helicobacter pylori infection, of three different antibiotics in combination with omeprazole and metronidazole, in order to establish which might be best in clinical practice. One hundred twenty three patients with HP-positivity, assessed by CLO-test and histology were studied. They were randomly assigned to the following therapies: clarithromycin (500 mg thrice daily) for 14 days, amoxycillin (twice daily) for 14 days, azithromycin (500 mg once daily) for 6 days, in combination with omeprazole (twice daily for 20 days and once for one month plus metronidazole (500 mg twice days) for 10 days. The eradication rate, among the three groups, was 97%, 80% and 68% respectively (p = 0.009); no statistical differences were remarked also between the group treated with amoxicyllin and that with clarithromycin, and between the group treated with amoxicyllin and that with azithromycin; there was only a statistical difference between the group treated with azithromycin and that with clarithromycin (p = 0.005). The Authors suggest that all the three antibiotics are effective in curing Helicobacter pylori infection and, that, the various use of the three antimicrobials should be evaluated from time to time on the basis of clinical data of the patients.

[The effects of eradication therapy in patients with chronic atrophic gastritis and seropositivity for anti-HP antibodies and histological negativity for Helicobacter pylori]. / Effetti della terapia eradicante in pazienti affetti da gastrite cronica atrofica con sieropositività per gli anticorpi anti-HP e negatività istologica per l'Helicobacter pylori.

PURPOSE: The present study was undertaken to analyze both whether the elevated Helicobacter pylori levels in patients with atrophic gastritis without histologic evidence of Helicobacter pylori would be a sign of an ongoing infection and the effects of eradication on gastric atrophy. PATIENTS AND METHODS: Twenty patients (10 M e 10 F; mean age 57.25 SD 12.19) with atrophic gastritis and elevated Helicobacter pylori titers without histological evidence for Helicobacter-like organisms were included in the study. Ten patients were randomized into eradication group (Group 1) (amoxicillin at 500 mg twice a day for 14 days, metronidazole at 500 mg twice a day for 10 days and omeprazole at 20 mg twice a day for 20 days) and 10 patients were randomized into the control group (Group 2). For all subjects, serum samples and duplicate biopsy specimens (obtained endoscopically) were collected prior the study period and approximately 6 months after the therapy or the follow-up for serum samples and 8 weeks for biopsy specimens. RESULTS: In the Group 1, the Helicobacter pylori antibody titers dropped significantly in 73.39% of the patients (p < 0.0001), while in the Group 2, the antibody titers declined only in a patient who received antibiotics during the study period (p < 0.00006). In both groups, no significant improvement of atrophic gastritis was observed. CONCLUSIONS: In conclusion, in patients with atrophic gastritis, the only histological evaluation of Helicobacter-like organisms colonization in gastric biopsy specimens, appeared in our study to underestimate the true prevalence of current HP infection and the importance of the bacterium in the pathogenesis and progression of such disease. Since HP infection is often associated with an increase of proliferative index, the eradication of HP could induce a mucosal protective effect against the other carcinogen factors, although it is extremely unlikely that it can promote the regeneration of a normal gastric mucosa.

[Malaria: recent immunological acquisitions and therapeutic prospects]. / La malaria: recenti acquisizioni immunologiche e prospettive terapeutiche.

Malaria remains one of the major health problems in many tropical countries. The asymptomatic carrier status is common and about 100% of the children in highly endemic areas have Plasmodium falciparum parasitaemia at any given time. Consequently a case definition based on the mere presence of parasites in the blood is non-informative in terms of measuring morbidity. Acquired clinical and parasitological immunity develop progressively over several years after repeated exposure to infection. Protection is acquired first again death or severe clinical disease, but protection against infection is never complete, moreover it is still not known why some infections are mild an some fatal. Although virulence markers on the parasite have not been identified with certainty, there are some indications that parasites differ in virulence. The genetic composition of human many also play a role in the defence against the parasite, so the immune mechanisms responsible for the acquired immunity remain uncertain. In fact, an infection by Plasmodium falciparum induces a variety of immune responses, including humoral and cellular, which can be specific or non-specific responses, some of which are protective, but against which the parasite has evolved effective escape measures. Vaccines has proven a most effective measure to control infectious diseases, but no consistently effective vaccine has yet developed against a human parasitic disease. A malaria vaccine aimed at disrupting the parasites life cycle at one or more of the three stages (sporozoite or pre-erythrocytic stage, asexual blood or erythrocytic stage, and sexual or sporogonic stage) might be a long-term solution.