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I Luzzi

Publications and source records attributed to I Luzzi.

At least 37 records · Page 2Linked to original sources
PubMed1997

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) short-term 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 30 mg once a day for 1 week, azithromycin 500 mg once a day for 3 days, and metronidazole 250 mg 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.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1997

Helicobacter pylori duodenal colonization in children.

To investigate the prevalence and the significance of Helicobacter pylori duodenal colonization, endoscopic duodenal biopsies were performed in 168 children with chronic abdominal pain, gastroesophageal reflux, gastrointestinal bleeding, and malabsorption syndrome. Helicobacter pylori infection was detected in 68 children (40.4%): in 31 of them H. pylori was present in the gastric antrum, and in 37 in the duodenum also. Duodenitis was observed in 25 children with duodenal H. pylori; gastric metaplasia in 3. Scanning electron microscopy revealed the presence of the micro-organism in 3/13 cases; the bacteria were located in the intercellular spaces and alterations of the epithelial surface were found. In conclusion, H. pylori gastritis in children is often associated with duodenal colonization which can cause duodenitis, and also without gastric metaplasia, which indicates a possible role of the micro-organism in the pathogenesis of the lesions.

Adolescent↗
PubMed1997

Does pretreatment with omeprazole decrease the chance of eradication of Helicobacter pylori in peptic ulcer patients?

OBJECTIVE: It has been reported that pretreatment with omeprazole could decrease the efficacy of Helicobacter pylori eradication. Our aim was to compare the efficacy, safety, and tolerability of the eradicating regimen, omeprazole/amoxicillin/metronidazole. The two antibiotics were scheduled either during the first or during the last 2 wk of omeprazole administration. METHODS: In this prospective controlled study conducted in a single center, 78 symptomatic peptic ulcer patients were treated for 4 wk with omeprazole 40 mg o.m.; the patients were randomly assigned to receive amoxicillin 1 g t.i.d. postprandially and metronidazole 250 mg t.i.d. postprandially, either during the first 2 wk (group A, n = 40) or the last 2 wk of therapy with omeprazole (group B, n = 38). H. pylori status was assessed by culture, histology, urease test, and IgG antibodies. Each patient's course was followed for 1 yr. RESULTS: H. pylori infection was cured in 97.4% of group A (95% CI: 0.84-0.99) and in 89% of group B (95% CI: 0.73-0.96, p = 0.28). Healing was achieved in 80% of the patients in group A (95% CI: 0.63-0.90) and in 75.7% of patients in group B (95% CI: 0.60-0.90, p = 0.60) At 12-month follow-up, 72 patients were evaluated: 37/38 (97%) of patients in group A and 33/33 (100%) in group B were confirmed as cured of the infection (NS). Peptic ulcer healing rate reached 100% in the two groups. Furthermore, between the two groups, there were no significant differences in symptom relief or improvement. Both regimens were well tolerated, and no patient had to be withdrawn from therapy because of an adverse event. Minor side-effects appeared to be similar in the two groups (40% vs. 38%). CONCLUSIONS: This randomized study clearly indicates that omeprazole pretreatment does not significantly reduce the efficacy of eradicating therapy for H. pylori in peptic ulcer patients.

Adult↗
PubMed1996

Detection of a vacuolating cytotoxin in stools from children with diarrhea.

A cytotoxin inducing vacuolation in HEp-2 cells was detected in 19 (3.1%) of 618 stool specimens from children with diarrhea but in none of 135 from control children. Common enteric pathogens were found in only two (10.5%) of the 19 cytotoxin-positive stool specimens. The vacuoles induced by stool filtrates resembled those induced by the vacuolating toxin (VacA) of Helicobacter pylori. The vacuolating toxin was heat-labile and protease-sensitive, and it had an apparent molecular weight of > 100,000 but was not neutralized by an antiserum to H. pylori VacA. Although proper prospective case-control studies are needed to definitely assess the etiologic association between the new vacuolating cytotoxin and diarrhea, the present study suggests that microorganisms of the gastrointestinal tract produce a Helicobacter-like vacuolating toxin and may be responsible for cases of childhood diarrhea whose etiology is currently considered unknown.

Bacterial Proteins↗
PubMed1996

Enteropathogens associated with childhood diarrhea in Italy. The Italian Study Group on Gastrointestinal Infections.

BACKGROUND: Infectious diarrheal diseases remain an important cause of childhood morbidity in industrialized countries. The knowledge of the etiology and epidemiology of childhood diarrhea in a given area is needed to plan any measure designed to prevent or ameliorate diarrheal illness and to develop practice guidelines for the most appropriate stool examination procedures. METHODS: We evaluated 618 children with diarrhea and 135 controls prospectively for viral, bacterial and parasitic enteric pathogens. Diarrheagenic Escherichia coli was identified by gene probes specific to different virulence factors. Stool filtrates were examined for the presence of free bacterial toxins by a cell culture cytotoxicity assay. Clinical and epidemiologic data were recorded and analyzed in relation to microbiologic findings. RESULTS: Enteropathogens were identified in 59% of children with diarrhea and in 10.4% of asymptomatic controls. The agents mainly associated with disease were rotavirus (23.6%), Salmonella (19.2%) and Campylobacter (7.9%). Rotavirus was significantly more frequent among children observed as inpatients whereas Campylobacter was significantly more common in outpatients. Infections with diarrheagenic E. coli, Shigella flexneri, yersinia enterocolitica, Cryptosporidium and Giardia were observed in a limited number of patients. The clinical presentation of children was not sufficiently characteristic to permit presumptive diagnosis of a specific pathogen. conversely the presence of blood and/or leukocytes in stools had a high positive predictive value for Salmonella or Campylobacter infection. CONCLUSION: The results of this study will be useful for planning strategies to prevent and control diarrheal diseases in our country.

Child↗
PubMed1996

Helicobacter pylori infection in families of Helicobacter pylori-positive children.

Relatives of Helicobacter pylori positive patients show a higher incidence of Helicobacter pylori infection than the general population, probably due to relapses and/or reinfections between members of the family. Aim of this study was to evaluate the prevalence of the infection in 121 relatives of 41 children with Helicobacter pylori positive gastritis. Specific IgG antibodies (ELISA) were evaluated, and bacteria on gastric biopsy specimens were investigated by urease-rapid test, culture test and GIEMSA or acridine orange staining. Of the eighty-two relatives, 68% were antibody positive. Thirty-five agreed to undergo endoscopy. With the exception of one brother, all subjects (97%) were found to be infected by Helicobacter pylori. Two symptomatic relatives, with normal antibody titres, were submitted to endoscopy and found to be colonized by Helicobacter pylori. The present data confirm the high prevalence of infection within families and appear to demonstrate the usefulness of endoscopy for all subjects showing positive antibody titres as well as for symptomatic relatives, even if serologically negative, to confirm the presence of any pathological conditions and reduce the risk of relapses within families.

Antibodies, Anti-Idiotypic↗
PubMed1995

Role of Clostridium difficile in childhood diarrhea.

To investigate the etiologic role of Clostridium difficile in childhood acute diarrhea, stool specimens from 618 children with diarrhea and 135 controls without enteric symptoms were examined by cell culture assay for the presence of free toxin B. This toxin was found in 4.2% of the fecal specimens examined without finding a significant difference between cases and controls, suggesting no causal relationship between diarrhea and the presence of free C. difficile toxin B. C. difficile strains isolated from toxin B-positive specimens were characterized by cytotoxin and enterotoxin production and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of EDTA-extracted proteins. All but two isolates produced toxin B and toxin A and the remaining were negative for both toxins. Polyacrylamide gel electrophoresis analysis showed eight electrophoretic types, none of them was clearly related with the cases of diarrhea. The majority of isolates from children with diarrhea did not belong to types previously observed in adults with pseudomembranous colitis or antibiotic-associated diarrhea. This study provides additional evidence that C. difficile is not involved in the etiology of childhood diarrhea.

Bacterial Toxins↗
PubMed1995

Pheno-genotyping of verotoxin 2 (VT2)-producing Escherichia coli causing haemorrhagic colitis and haemolytic uraemic syndrome by direct analysis of patients' stools.

The subtype of verotoxin 2 (VT2) found in 22 VT2-positive stool samples from severely diseased Italian and German children with haemorrhagic colitis or haemolytic uraemic syndrome, or both, and that produced by the corresponding VT-producing Escherichia coli (VTEC) strains isolated from the stools were studied by cytotoxicity seroneutralisation assays and by polymerase chain reaction (PCR) amplification of the VT2 B-subunit gene, followed by restriction fragment length polymorphism (RFLP) analysis. The free faecal toxin was serotyped as the classical VT2 in 21 stool samples, and as the VT2 variant VT2c in one. For all but one of the VTEC isolates, the toxin phenotype was consistent with the type of VT produced in vivo and found in the corresponding stool samples. Genotyping was in agreement with phenotyping for those strains harbouring a single type of VT2 gene. Three O157:H7 isolates carrying both VT2 and VT2c genes had the VT2 phenotype, instead of the expected VT2c phenotype. Direct PCR analysis of stools detected VT genes in only 11 of 20 VT-positive stool samples suggesting that the Vero cell cytotoxicity assay is more sensitive in diagnosing VTEC infection. Immunological and genetic subtyping of VT2 performed directly on stool samples from patients with haemolytic uraemic syndrome could be a useful complementary approach to understanding the role of the different types of VT in this syndrome.

Animals↗
PubMed1995

Ulcerative colitis precipitated by a verocytotoxin-producing Escherichia coli infection.

The aetiology of ulcerative colitis remains unknown, despite extensive research into likely causes, such as infections, diet, environmental factors, immunological or genetic defects, psychomotor disorders, and abnormalities of mucin. We report here a case of ulcerative colitis in which the first episode of the disease was associated with serologic evidence of infection by verocytotoxin (VT)-producing O157 Escherichia coli (VTEC), possibly the trigger factor of a previously silent ulcerative colitis. Although histological reports of ulcerative colitis associated with VTEC infection are sporadically reported, the trigger role of VTEC in precipitating, aggravating or prolonging this pathology should be more fully elucidated.

Adult↗
PubMed1994

Haemolytic-uraemic syndrome in childhood: surveillance and case-control studies in Italy. Italian HUS Study Group.

Seventy-six cases of haemolytic-uraemic syndrome (HUS) were collected over a 4-year period during a surveillance and case-control study. The annual incidence of 0.2 per 100,000 children aged 0-14 years is lower than in other countries; 34% had no prodromal diarrhoea. Evidence for verocytotoxin-producing Escherichia coli (VTEC) infection was found in 72% of patients and 3% of controls; 88% of patients with bloody diarrhoea, 67% with non-bloody diarrhoea and 55% without diarrhoea were VTEC positive. Seventy-three percent of patients had creatinine clearance > or = 80 ml/min per 1.73 m2, normal blood pressure, no proteinuria and haematuria < 2+ after 1 year of follow-up. One patient died and none had non-renal sequelae. VTEC positivity was significantly correlated with a good outcome, while the absence of diarrhoea and a high total white blood cell count at onset were not predictors of a bad outcome. Household contacts of HUS patients had diarrhoea more frequently than those of the control group, supporting the hypothesis of person-to-person transmission of VTEC infection.

Adolescent↗
PubMed1994

A community outbreak of haemolytic-uraemic syndrome in children occurring in a large area of northern Italy over a period of several months.

From March to October 1993, 15 cases of haemolytic-uraemic syndrome (HUS) in children were detected in a large area of northern Italy, where only 8 cases had occurred in the previous 5 years. Analysis of stool and serum specimens obtained from 14 cases showed evidence of Verotoxin-producing Escherichia coli (VTEC) infection in 13. Serum antibodies to the E. coli O157 lipopolysaccharide (LPS) were found in 8 patients and to the O111 LPS in 2. An O86 VTEC was isolated from another patient. Fourteen children needed dialysis, and 1 died. No obvious epidemiologic link was observed among cases, most of whom lived in small townships. A case-control study did not show an association between HUS and food or exposure to cattle, but suggested an association with contact with chicken coops (OR = 6.5, 95% C.I. 1.2-34.9). However, VTEC were not isolated from stool samples obtained from the chicken coops involved. The risk factors for VTEC infection related to living in rural settlements, including the exposure to live poultry, should be considered in outbreak investigations.

Animals↗
PubMed1994

Community-wide outbreak of hemolytic-uremic syndrome associated with non-O157 verocytotoxin-producing Escherichia coli.

From 20 April through 13 May 1992, 9 children were hospitalized with hemolytic-uremic syndrome in Lombardia, Italy, where only 14 cases of this syndrome had occurred in the preceding 4 years. Cases were scattered in a large area encompassing five provinces, and the source of the outbreak was not identified. Eight patients needed dialysis, and there was 1 death. Seven of the 9 cases were examined for evidence of infection by Vero cytotoxin (VT)-producing Escherichia coli (VTEC). Six children had serum antibodies to the lipopolysaccharide of E. coli O111, and a VT-producing E. coli O111:NM was isolated from stool in 1 case. This is the first outbreak of VTEC infection recognized in Italy and the first associated with an E. coli serotype other than O157:H7.

Antibodies, Bacterial↗
PubMed1994

[High incidence of Helicobacter pylori infections in an endoscopic pediatric patient series].

We evaluated in children with abdominal complaints the prevalence of Helicobacter pylori gastric and duodenal colonization and the histological features of gastric and duodenal mucosae. Fifty patients, aged 1-17 years, underwent upper endoscopy for recurrent abdominal pain, vomiting and/or gastrointestinal bleeding. With serological, bacteriological and/or histological methods twenty-eight children were demonstrated to be Helicobacter pylori-positive. No statistically significant differences were observed with regard to age, sex and indication to perform endoscopy. Eighty-two percent of Helicobacter pylori-positive patients had gastritis and/or duodenitis. The Helicobacter pylori-positive children had higher Helicobacter pylori specific IgG levels than the Helicobacter pylori-negative ones (p < 0.001). No statistically significant differences were found between Helicobacter pylori-positive and Helicobacter pylori-negative subjects, for gastrin and pepsinogen I. Since the frequency of Helicobacter pylori infection in children with gastrointestinal complaints is high, in patients undergoing upper endoscopy, the sistematical examination of bioptic samples for bacteriological and histologic procedures is of great importance.

Abdominal Pain↗
PubMed1992

Impaired detection of faecal verocytotoxin in the presence of Clostridium difficile cytotoxin in patients with haemolytic uraemic syndrome.

Three cases of haemolytic uraemic syndrome associated with infection with verocytotoxin producing Escherichia coli are described. The concomitant presence of Clostridium difficile cytotoxin in the patients' stool impaired the detection of free faecal verocytotoxin. Stool specimens containing Clostridium difficile cytotoxin should thus be considered negative for verocytotoxin only after neutralisation of the Clostridium difficile cytotoxin with antitoxin.

Animals↗