Occurrence, removal and seasonal variation of thermophilic campylobacters and Arcobacter in sewage sludge.

The presence of thermophilic campylobacters and Arcobacter was investigated in four types of sewage sludge taken from the treatment plant in Bologna (Italy): primary, activated, thickened and anaerobically digested sludge. Campylobacter jejuni and Campylobacter coli were more numerous during the March-September period and were found only in primary sludge (22.7%) with mean counts of 278 MPN/g dry matter and 1403 MPN/g dry matter respectively. Arcobacter butzleri were found in all types of sludge with frequencies of 80% in activated and thickened sludges and 41% in digested sludges. They were more numerous in the spring/summer period with peaks in April, May, June and September. They were less sensitive to anerobic digestion than fecal bacteria, probably due to their microaerophilic growth properties. However, since they are found in anaerobically digested sludges at mean values of 7649 MPN/g dry matter the land application of digested sludges may cause high risks infection.

Reversal of fundic atrophy after eradication of Helicobacter pylori.

OBJECTIVES: We sought to evaluate the effect of Helicobacter pylori eradication in patients with fundic atrophic gastritis. METHODS: Acid secretion, gastric emptying, and histology were evaluated in 20 patients with fundic atrophic gastritis and H. pylori infection. After investigation, 10 patients (Group 1) received an eradicating treatment and 10 (Group 2) did not receive any treatment. One year later, the baseline investigations were repeated. Subsequently, patients in Group 2 received the same treatment given to patients in Group 1 and were reevaluated 12 months later. A further follow-up was performed in both groups 36 months after the treatment. RESULTS: At 1-yr follow-up, all the patients in Group 1 were H. pylori negative whereas all the patients in Group 2 were still infected. In Group 1, there was a significant improvement of both fundic atrophy and acid secretion, compared with baseline (p < 0.01). In Group 2, no substantial modification of either histological or functional parameters was observed at the first follow-up; conversely, a significant (p < 0.01) improvement of fundic atrophy and acid secretion was detected in these patients 12 months after eradication of the bacterium. Histological pattern remained unchanged at 36 months of follow-up in both groups. Gastric emptying remained, on the average, unaffected by the treatment; however, three patients with delayed gastric emptying at entry had normal gastric emptying after eradication of H. pylori. CONCLUSIONS: Our data suggest that mucosal atrophy can be reduced or even reversed by the eradication of H. pylori, and this is associated with a recovery of gastric function.

Evaluation of short-term low-dose triple therapy for the eradication of Helicobacter pylori by factorial design in a randomized, double-blind, controlled study.

BACKGROUND: Studies demonstrating the efficacy of short-term low-dose triple therapies including omeprazole (O), clarithromycin (C) and a nitroimidazole (tinidazole, T) for Helicobacter pylori eradication have largely been open and uncontrolled, and have not assessed antibiotic sensitivity. Simpler regimens using the component drugs have not been evaluated. AIM: To evaluate the OCT regimen in a randomized, controlled trial, testing for pre- and post-treatment antibiotic resistance and comparing, in a factorial design, the OCT regimen with simpler combinations of its components. METHODS: One hundred and twenty-eight patients (68 males, 60 females, age 22-80 years, mean 53 years) with H. pylori gastritis were randomly assigned to one of the following four treatment groups: (C) clarithromycin 250 mg b.d.; (OC) omeprazole 20 mg o.d. + clarithromycin 250 mg b.d.; (CT) clarithromycin 250 mg b.d. + tinidazole 500 mg b.d.; (OCT) omeprazole 20 mg q.d.s. + clarithromycin 250 mg b.d. + tinidazole 500 mg b.d. The drugs were administered for 1 week. Medical interview, upper gastrointestinal endoscopy (with four antral and four corpus biopsies) and the 13C-urea breath test were carried out for all patients prior to and 4 weeks after treatment. Biopsy specimens were used for the urease test, histology, and culture and sensitivities. RESULTS: All but one patient completed treatment. Side-effects were rare and mild in all groups. The eradication rate was 93.8% in group OCT, 59.4% in group CT, 31.3% in group OC and 6.3% in group C. Pre-treatment metronidazole resistance was 12.8%, clarithromycin 1.1% and, to both antibiotics, 2.1%. In patients with pre-treatment metronidazole resistance, the eradication rate was 75% in group OCT and 33% in group CT. Post-treatment resistance to clarithromycin was induced in 28.5% of the failures in group C, but in none of group OC. Resistance to both antibiotics occurred in 22.2% of the failures in group CT and in none of group OCT. CONCLUSIONS: (i) The high efficacy of the OCT regimen is proved and each of the individual components of the regimen is essential to the result, possibly via a synergistic effect. (ii) Pre-treatment metronidazole resistance is scarcely relevant to the outcome. (iii) Acquired resistance is essentially nil if omeprazole is part of the regimen.

Detection of serum antibodies to CagA and VacA and of serum neutralizing activity for vacuolating cytotoxin in patients with Helicobacter pylori-induced gastritis.

Thirty patients with dyspepsia, with histological diagnosis of gastritis, and with endoscopic diagnosis of peptic ulcer disease (PUD) (n = 13) or nonulcer dyspepsia (NUD) (n = 17) were admitted to the study. Helicobacter pylori vacuolating cytotoxin-producing strains (Tox+) were isolated from 14 (46.7%) patients, whereas non-cytotoxin-producing (Tox-) H. pylori strains were isolated from the remaining patients. Of 30 patients studied, 20 (66.7%) had serum cytotoxin neutralizing activity in vitro. Fourteen patients with Tox+ H. pylori strains showed serum cytotoxin neutralizing activity and serum immunoglobulin G (IgG) and IgA antibodies reactive with both 87-kDa H. pylori vacuolating cytotoxin (VacA) and 128-kDa cytotoxin-associated gene product (CagA) by immunoblotting using native enriched preparations of VacA and CagA proteins from H. pylori culture supernatants as the antigens. A 94-kDa antigen cross-reacting with the 87-kDa VacA protein could be demonstrated in culture supernatant with immune sera from humans and animals. All patients (n = 10) lacking serum neutralizing activity were also negative for IgG or IgA against VacA antigen, whereas 6 of the 10 patients showed IgG serum antibody responses against CagA antigen. The prevalence of antibodies to VacA and CagA antigens was significantly (P < 0.001) higher in patients with gastritis (20 and 26 patients for VacA and CagA, respectively, of 30 patients) than in H. pylori culture-negative controls (0 of 27 for both VacA and CagA) and in randomly selected blood donors (17 and 21 for VacA and CagA, respectively, of 120 subjects). All patients with PUD had antibodies to CagA, whereas 13 of 17 (76.5%) patients with NUD had anti-CagA antibodies. Serum IgG antibodies to VacA were present in 9 (69.2%) patients with PUD of 13 patients and in 11 (64.7%) patients with NUD of 17 patients. Anti-CagA antibodies seemed to correlate better with PUD than anti-VacA antibodies.

Prevalence of thermophilic Campylobacter and Arcobacter butzleri in food of animal origin.

Thermophilic campylobacters and Arcobacter butzleri were looked for in 57 manually shelled egg samples and 130 raw meat samples. No bacteria were found in the egg samples, but they were, however, found in 16.1% of meat samples with a frequency varying from 2.4% (port sausage) to 37.5% (poultry). A total of 21 strains were identified, one belonging to Arcobacter butzleri (pork) and 20 to Campylobacter. The most common species was C. jejuni (16/20) followed by C. coli (4/20) and in both species biotype I was the most frequently found. Regarding the methods employed for the isolation of bacteria, no substancial difference was seen between the three media (Butzler, CCDA and Preston) although CCDA medium gave better results than Butzler and Preston media. The variable which had the most influence was the incubation temperature. A higher number of strains was obtained at 42 degrees C than at 37 degrees C.

Value of serology (ELISA) for the diagnosis of Helicobacter pylori infection: evaluation in patients attending endoscopy and in those with fundic atrophic gastritis.

In the present study we assessed the diagnostic accuracy of four commercial IgG enzyme-linked immunosorbent assay (ELISA) kits (Autoplate, H.pylori-EIA-Well, Enzygnost, Helori-test) and evaluated the performance of these tests in patients with fundic atrophic gastritis. Serum antibodies to Helicobacter pylori were measured in 70 out-patients attending endoscopy for dyspepsia and 43 patients with non-autoimmune fundic atrophic gastritis. Using the cut-off values recommended by the manufacturers, and comparing serological findings with gastric biopsy results of dyspeptic out-patients attending endoscopy, the four kits showed a sensitivity and specificity, respectively, of 91% and 96%, for Autoplate, 67% and 100% for H.pylori-EIA-Well, 79% and 100% for Enzygnost, and 81% and 96% for Helori-test. Evaluation in patients with atrophic gastritis revealed a high prevalence of antibodies to Helicobacter pylori (84%) and it demonstrated that patients with and those without gastric colonization by this microorganism had a similar rate of seropositivity (76-84% vs 50-78%). In conclusion, our data demonstrate that: a) this assay is a reliable and valid method to detect gastric colonization by Helicobacter pylori; b) positive serum antibody associated with a negative detection of Helicobacter pylori in the gastric mucosa suggests mucosal atrophy; c) patients with fundic atrophic gastritis should be excluded from studies investigating the value of serology in diagnosing Helicobacter pylori infection.

Comparative disinfection of secondary-treated sewage with chlorine dioxide and bromine chloride.

A comparison was made of the inactivation rates of Arcobacter butzleri, coliphages, total coliforms, fecal coliforms, fecal streptococci and heterotrophic plate count in secondary sewage effluent using chlorine dioxide (2 and 4 ppm) and bromine chloride (4 or 8 and 12 ppm) as disinfecting agents. Using these doses the ClO2 gave higher reduction percentages (on average more than 99% at 4 ppm) than those obtained with BrCl. The average values of the fecal indicators are well within the legal limits. Arcobacter butzleri was more sensitive to the disinfectants than other bacteria while fecal streptococci were seen to be more resistant. From the chemical point of view no differences were seen between the two disinfectants except that the action of ClO2 was stronger regarding BOD5 than that of BrCl. With the exception of dichloromethane, the concentration of volatile halogenated compounds showed little variation and values were often lower than detection limits.

Evaluation of two therapeutic regimens for the treatment of Helicobacter pylori infection.

In the present study we evaluated the efficacy and tolerability of two different therapeutic schedules in eradicating Helicobacter pylori. Forty-six consecutive patients (suffering from either peptic ulcer or non-ulcer dyspepsia) with helicobacter pylori infection were randomly allocated to one of the following two groups: group 1 (n = 23) 2 weeks of treatment with bismuth subcitrate tablets (120 mgx4) + amoxycillin capsules (500 mgx4) + metronidazole tablets (250 mgx4); group 2 (n = 23) 2 weeks of treatment with amoxycillin capsules (500 mgx4) + metronidazole tablets (250 mgx4). Endoscopy, histology and bacterial culture were performed at entry, and 30 and 90 days after treatment. Two group 1 patients and one group 2 patient did not complete the treatment. Successful eradication was obtained in 20/21 (95%) patients treated with triple therapy (group 1) and in 17/22 (77%) patients treated with double therapy (group 2) (p = 0.2). Side-effects occurred in 9/21 (43%) patients of group 1 and in 9/22 (41%) patients of group 2 (p = 0.9). These were all self-limiting and required no specific treatment. These data suggest that combined therapy with amoxycillin and metronidazole, with or without bismuth subcitrate, represents a safe and effective therapeutic approach for the treatment of Helicobacter pylori infection. In our series, triple therapy determined a numerically higher eradication rate than double therapy.

One-day therapy for treatment of Helicobacter pylori infection.

The present study evaluated the effect of a one-day high-dose combined therapy on Helicobacter pylori infection. Thirty-two consecutive patients (suffering from either peptic ulcer or nonulcer dyspepsia) with Helicobacter pylori infection received omeprazole (40 mg) + bismuth subcitrate (240 mg x 4) + amoxicillin suspension (2000 mg x 4) + metronidazole (500 mg x 4), for only one day. Endoscopy, histology, culture, and susceptibility studies were done at entry and 30 and 90 days after the treatment day. Successful eradication was obtained in 23/32 (72%) patients and gastritis had resolved in 95% of these. Side effects were induced by the treatment in 6/32 (19%) patients, but these were all self-limiting, short-lasting, and did not require any specific treatment. Development of bacterial resistance to metronidazole occurred in 6/9 (67%) non-eradicated patients. These data suggest that one-day treatment with high doses of amoxicillin, metronidazole, bismuth, and omeprazole represents an effective, safe, and inexpensive therapeutic approach for the treatment of H. pylori infection.

Arcobacter cryaerophilus and thermophilic campylobacters in a sewage treatment plant in Italy: two secondary treatments compared.

Microaerophilic organisms were monitored in sewage effluent undergoing two secondary treatments: air and oxygen-activated sludge. The mean numbers of Arcobacter cryaerophilus and thermophilic campylobacters detected in incoming sewage were 5639/100 ml and 1720/100 ml respectively. Secondary treatment in air tanks reduced the population of A. cryaerophilus by 97.1% and of thermophilic campylobacters by 99.08%, whereas treatment in oxygen tanks reduced the bacteria 97.8% and 99.63% respectively, showing that oxygen-activated sludge treatment was more effective. Subsequent tertiary treatment with 2 p.p.m. chlorine dioxide evidenced the removal of A. cryaerophilus to 99.9% and eliminated thermophilic campylobacters. Campylobacter jejuni and C. coli constituted 54.1% and 45.9% of 74 thermophilic campylobacter strains isolated. In air-activated sludge effluent C. jejuni was found more often, thus appearing more sensitive to oxygen. The most probable number assay used for detection of campylobacters, blood medium for enrichment and blood-free medium for plating, also appeared to be fit for A. cryaerophilus, the high density of which in urban sewage may be due to inflows from slaughterhouses.

Evaluation of Helicobacter pylori sensitivity to amoxycillin and metronidazole in dyspeptic patients.

We evaluated the "in vitro" sensitivity to amoxycillin and metronidazole of 193 Helicobacter pylori strains isolated from the gastric mucosa of dyspeptic patients. Susceptibility was determined by disc diffusion on agar plates. All the isolates were found to be sensitive to amoxycillin. On the contrary, 12% of the strains isolated from patients never treated for Helicobacter pylori infection and 73% of those isolated from patients who had previously received unsuccessful treatment for Helicobacter pylori infection were found to be resistant to metronidazole. Resistance was more common in women (17%) than in men (4%: p < 0.01) and was not correlated with age. The occurrence of Helicobacter pylori resistance to metronidazole is relatively common in Italy. In vitro testing of Helicobacter pylori sensitivity seems to be important before embarking on treatments aimed at eradicating the bacterium.

Occurrence, removal and seasonal variation of "thermophilic" campylobacters in a sewage treatment plant in Italy.

Monitoring of "thermophilic" campylobacters in a sewage treatment plant in Bologna (Italy) has shown that incoming sewage contained a most probable number of 1630 campylobacters/100 ml. The secondary treatment in activated sludge tanks reduced 98.61% of campylobacters, 95.32% of fecal coliforms, 96.46% of fecal streptococci, 93.36% of salmonellas and 93.01% and 88.29% of BOD5 and COD respectively. Subsequent tertiary treatment with 3 ppm of chlorine dioxide for 15 min reduced 100% of campylobacters and salmonellas. Significant correlation coefficients were found in incoming sewage between campylobacters and salmonellas (p < 0.01) and between campylobacters and fecal coliforms (p < 0.02). Campylobacter jejuni and Campylobacter coli constituted 51.3% and 48.7% respectively of the 80 strains isolated. In incoming sewage 66% of the strains isolated were found to be Campylobacter jejuni whereas Campylobacter coli strains were prevalent in activated sludge effluent (69.7%). The greatest frequency of isolation and the higher counts were obtained during the Spring to Summer period with distinct peaks in May, June and July. This seasonability is probably due to the seasonal variation of campylobacter infections in man and animals.

Helicobacter pylori infection and gastric function in patients with chronic idiopathic dyspepsia.

Helicobacter pylori infection, histological features of the gastric mucosa, and gastric motor and secretory functions were evaluated in 45 consecutive patients with chronic idiopathic dyspepsia. H. pylori infection was found in 60% of dyspeptic patients, compared with 33% of 15 healthy controls (P = 0.1). No difference was detected in basal or stimulated gastric acid secretion between dyspeptic patients and healthy controls. Gastric emptying was significantly (P less than 0.01) delayed in dyspeptic patients compared with healthy controls when standardized for age and sex. Delayed gastric emptying was associated with a low frequency of H. pylori infection, female gender, and young age. Epigastric pain or burning and postprandial fullness were, respectively, more severe in patients with H. pylori infection (P less than 0.02) and in those with delayed gastric emptying (P less than 0.01). These findings support the existence of separate subsets of patients with chronic idiopathic dyspepsia. Despite the presence of overlaps, there appear to be partially different functional derangements and clinical features in different subgroups of dyspeptic patients.

Observations made on strains of Campylobacter spp. isolated in 1989 in northern Italy.

Over a 12-month period (1989), 192 thermophilic campylobacters (190 from stool and two from blood specimens) were isolated. All the strains were identified as far as species and biotype was concerned and 89 were also serotyped according to the Lior method. C. jejuni (90.10%) was the species most frequently isolated (mainly biotype I) while the most frequent serogroup was LIO 4. Erythromycin-resistance was found in only 15 strains, but while it was very low for the species C. jejuni (1.16%), it was frequent for C. Coli (68.42%), mainly for biotype I (73.33%). Moreover, eight strains of thermophilic campylobacters resistant to nalidixic acid (three strains of C. jejuni and five strains of C. coli) were found.

Antibodies to Campylobacter pylori in patients with idiopathic dyspepsia.

We used Western Blotting analysis to determine the immune profile to Campylobacter pylori polypeptides in: A) sera from patients with idiopathic dyspepsia and bacteriological evidence of C. pylori gastric colonization, B) sera from patients with the same symptoms but no bacteriological evidence of C. pylori infection and C) healthy subjects. To avoid interference of aspecific reactions due to antigenic cross reactivity with other thermophilic Campylobacter species, antisera were raised in rabbits against C. pylori as well as against C. coli and C. jejuni. Some bands (with an approximate molecular weight of 118, 85, 40, 34, 28, 18 and 12 Kd) which can be considered specific for C. pylori were identified and the IgG reaction to some of them (40, 34, 28 Kd) was shown to be significantly higher in patients with bacteriological evidence of C. pylori infection than in the other two groups. IgM reactivity to two bacterial proteins of molecular weight 118 and 40 Kd was particularly evident in the second group of patients suggesting a possible diagnostic tool to identify C. pylori infection at a very early stage.

A one-year study on thermophilic campylobacters isolated from fecal specimens.

During a 12-month period, a systematic screening for thermophilic campylobacters was done on 5723 stool samples of hospitalized patients and out-patients who required stool culture tests for gastrointestinal disturbances. Campylobacter strains were isolated in 130 samples (2.27%) and Campylobacter jejuni (mainly biotype II) was the species most frequently isolated. No pronounced seasonal pattern was evident and the age at which infection was more often observed was that from 6 to 24 months. Erythromycin-resistance was found in only 8 strains and it was significantly more frequent among Campylobacter coli strains.