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Biomedical subjects

F Perri

Publications and source records attributed to F Perri.

At least 37 records · Page 2Linked to original sources
PubMed1998

The 13C-urea breath test as a predictor of intragastric bacterial load and severity of Helicobacter pylori gastritis.

BACKGROUND: The urea breath test (UBT) has been proposed as the most accurate test for diagnosing Helicobacter pylori infection. The aim of this work was to evaluate the accuracy of the UBT and to compare the results with histologic and endoscopic findings in H. pylori infected patients. METHODS: One-hundred-and-seventy-two consecutive dyspeptic outpatients were studied by means of endoscopy (with histology and culture), UBT (75 mg 13C-urea), and serology. Gastritis was classified in accordance with the Sydney criteria. In H. pylori positive patients, the bacterial load was assessed semiquantitatively, the number of bacteria in histologic specimens being counted. UBT results were expressed either as percentage cumulative dose of 13CO2 excreted at 1 h (CD60) or delta over baseline at 30' (DOB30). RESULTS: Of 172 patients, 126 (73%) were H. pylori positive on histology or culture. Using a cut-off value of 3.3/1000 for DOB30, the sensitivity, specificity and accuracy of the UBT were 96%, 93.5%, and 95.3%, respectively. A significant correlation was observed between DOB30 values and intragastric bacterial load (r = 0.32). Moreover, a significant difference in DOB30 values was found between patients sorted by the depth of inflammation (chi(2) = 4.36, p = 0.036). No correlation was observed between DOB30 and endoscopic findings in H. pylori positive subjects. CONCLUSIONS: The UBT is an accurate non-invasive diagnostic tool and can be used to predict both the intragastric bacterial load and the severity of related gastritis.

Adult↗
PubMed1998

Genome search in celiac disease.

Celiac disease (CD), a malabsorption disorder of the small intestine, results from ingestion of gluten. The HLA risk factors involved in CD are well known but do not explain the entire genetic susceptibility. To determine the localization of other genetic risk factors, a systematic screening of the genome has been undertaken. The typing information of 281 markers on 110 affected sib pairs and their parents was used to test linkage. Systematic linkage analysis was first performed on 39 pairs in which both sibs had a symptomatic form of CD. Replication of the regions of interest was then carried out on 71 pairs in which one sib had a symptomatic form and the other a silent form of CD. In addition to the HLA loci, our study suggests that a risk factor in 5qter is involved in both forms of CD (symptomatic and silent). Furthermore, a factor on 11qter possibly differentiates the two forms. In contrast, none of the regions recently published was confirmed by the present screening.

Celiac Disease↗
PubMed1998

Helicobacter pylori infection may undergo spontaneous eradication in children: a 2-year follow-up study.

BACKGROUND: Helicobacter pylori infection is generally acquired early in life. However, it is still unknown whether a spontaneous eradication can occur. The purpose of this study was to evaluate whether H. pylori infection can undergo spontaneous eradication in children. METHODS: Three hundred and four Italian children (age range, 4.5 to 18.5 years) were tested for H. pylori by means of 13C-urea breath test. Infected children were followed up every 6 months for as long as 2 years. Parents were instructed to record consumption of antibiotics. At each visit, children underwent a repeat 13C-urea breath test. RESULTS: Eighty-five out of 304 (27.9%) children were H. pylori infected. Forty-eight out of 85 infected children (56.4%) participated in the follow-up study. After 2 years, 8 (16.6%) infected children had negative results on 13C-urea breath tests; 2 of them were given antibiotics for concomitant infections. One child was negative at 6 months but became positive again at the next 6-month 13C-urea breath test. Forty children remained persistently positive; of them, 10 were treated with a short course of antibiotics. CONCLUSIONS: Our findings support the hypothesis that, at least during childhood, H. pylori infection may be a fluctuating disease with spontaneous eradication and possible recurrence.

Adolescent↗
PubMed1998

Intraduodenal lipase activity in celiac disease assessed by means of 13C mixed-triglyceride breath test.

BACKGROUND: In patients with celiac disease, the occurrence of exocrine pancreatic insufficiency has been related to an impairment of the gut-mediated stimulatory effect of the meal on the pancreas. The purpose of this study was to assess the intraduodenal lipase activity in patients with celiac disease by means of the 13C mixed-triglyceride breath test and to monitor pancreatic function after the institution of a gluten-free diet. METHODS: Seventeen untreated patients with celiac disease (mean age, 17.4 +/- 10.5 years) were studied. After an overnight fast, patients were given a standard test meal consisting of 100 g of white bread and 0.25 g of butter per kilogram of body weight, to which 16 mg di-stearyl-13C-octanoyl-glyceride (mixed triglyceride) had been added. Breath samples were taken twice at baseline and at 30-minute intervals for 6 hours after the meal. 13C enrichment in breath was determined by means of Isotope Ratio Mass Spectrometer (IRMS) (ANCA-NT; Europa Scientific, Crewe, UK). Results were expressed as the maximum percentage of 13C recovery per hour at any time, the time to reach peak excretion of 13C, and the percentage of 13C cumulative dose over 6 hours. RESULTS: Mixed-triglyceride breath test results were pathologic in three patients and at the lower limit of the normal range in another patient. In the remaining 13 patients, the results were within normal values. At the 6- and 12-month follow-ups, all patients showed normal intraduodenal lipase activity. CONCLUSIONS: In approximately 24% of patients with celiac disease, the intraduodenal pancreatic lipolytic activity is impaired. The mixed-triglyceride breath test could be used to assess fat maldigestion and to monitor the need for enzyme replacement therapy in such patients.

Adolescent↗
PubMed1998

Patterns of symptoms in functional dyspepsia: role of Helicobacter pylori infection and delayed gastric emptying.

OBJECTIVE: Functional dyspepsia (FD) is a syndrome in which several causes are probably involved. Our aim was to investigate the association between specific dyspeptic symptoms and Helicobacter pylori infection or delayed gastric emptying. METHODS: Nine hundred thirty-five consecutive outpatients with unexplained dyspepsia were studied. After appropriate investigation, 304 patients were diagnosed as affected by chronic FD and were tested for H. pylori infection and gastric emptying of solids by means of 13C-urea and 13C-octanoic acid breath tests. Four dyspeptic symptoms (epigastric pain or burning, postprandial fullness, nausea, and vomiting) were scored as absent, mild, moderate, or severe (0-3) according to their influence on the patients' activities. Symptoms of irritable bowel syndrome and gastroesophageal reflux disease were also assessed. On the basis of symptom scores, three groups were identified: "prevalent pain" (10.5%), "prevalent discomfort" (32.6 %), and "unclassifiable" dyspepsia (56.9%). RESULTS: Of the 304 patients with FD, 208 (68.4 %) were H. pylori-positive on urea breath test. Gastric emptying was delayed in 99 subjects (32.6%). Patients with "prevalent pain" were infected significantly more often (81.2% vs 59.6%; p = 0.026) and less frequently had delayed gastric emptying (6.2% vs 40.4%; p = 0.0001) than those with "prevalent discomfort." H. pylori infection was independently associated with age > or =40 yr and epigastric pain or burning > or =2 (odds ratio [OR] and 95% confidence interval [CI] 4.09 [2.39-7.00] and 1.70 [1.04-2.77], respectively). Delayed gastric emptying was independently associated with a cumulative score > or =6 for postprandial fullness, nausea, and vomiting (OR [95% CI]: 3.13 [1.06-9.18]). H. pylori status had no influence on gastric emptying. Logistic regression analysis showed that delayed gastric emptying, female sex, and concomitant symptoms of inflammatory bowel syndrome were independently associated with a cumulative score > or =6 for postprandial fullness, nausea, and vomiting (p = 0.0281, p = 0.0387, and p = 0.0316, respectively). Moreover, concomitant symptoms of gastroesophageal reflux disease, female sex, and H. pylori infection were independently associated with epigastric pain or burning > or =2 (p = 0.002, p = 0.0001, and p = 0.0875, respectively). CONCLUSIONS: Two subsets of FD patients have been identified on the basis of symptoms. One subgroup is mainly characterized by "prevalent pain," H. pylori infection, and normal gastric emptying; the other one demonstrates "prevalent discomfort" and delayed gastric emptying. These findings shed some light on possible etiopathogenetic mechanisms of FD.

Adult↗
PubMed1998

Methodological problems and pitfalls of urea breath test.

Although several papers on the urea breath test have been published, some methodological questions are still unsolved: the dose of 13C-urea, the test meal composition, the breath sampling, the fasting or fed condition, the postural settings, and the cut-off points. Moreover, special conditions, such as those occurring in paediatric and uraemic patients or subjects with previous gastric surgery should be borne in mind when evaluating the 13C-urea breath test results. This review focuses on methodological problems and potential pitfalls which can affect the accuracy of the 13C-urea breath test.

Adult↗
PubMed1998

HLA antigens and pANCA define ulcerative colitis as a genetically heterogeneous disorder.

BACKGROUND: Several genetic and subclinical markers have been associated with ulcerative colitis. AIM: To determine whether a significant association with HLA class I and II antigens was present in Italian ulcerative colitis patients considered as a whole population or stratified according to their anti-neutrophil cytoplasmatic antibodies. METHODS: HLA class I and II antigens were studied by serological typing techniques and related to the presence of anti-neutrophil cytoplasmatic antibodies detected by means of indirect immunofluorescence. RESULTS: Patients with ulcerative colitis (n = 45) had a significantly increased frequency of DQ6 (p = 0.04) and DQ7 (p = 0.003) and a decreased frequency of DQ5 (p = 0.03) and DQ8 (p = 0.02) when compared with ethnically matched healthy controls (n = 252 for HLA class I and 173 for HLA class II). No significant difference in HLA I- and DR-antigens was observed. Anti-neutrophil cytoplasmatic antibodies were found in 27/45 (60%) ulcerative colitis patients and in 0/252 controls (p < 0.001). After stratifying ulcerative colitis patients according to their anti-neutrophil cytoplasmatic antibodies status, anti-neutrophil cytoplasmatic antibodies +ve patients had an increased frequency of A19 (p = 0.007), DR2 (p = 0.03), and DR15 (p = 0.006), and a decreased frequency of A1 (p = 0.004) compared with anti-neutrophil cytoplasmatic antibodies -ve ones. CONCLUSIONS: We suggest that specific HLA-class II loci play an important role in the susceptibility to ulcerative colitis in Italy. A subset of ulcerative colitis patients is characterised by the presence of a specific subclinical marker (anti-neutrophil cytoplasmatic antibodies) which seems to be genetically determined as shown by the increased frequencies of HLA-A19 and DR2 observed in anti-neutrophil cytoplasmatic antibodies +ve ulcerative colitis.

Adult↗
PubMed1998

Relationship between the results of pre-treatment urea breath test and efficacy of eradication of Helicobacter pylori infection.

AIMS: This study was carried out to evaluate whether the 13C-urea breath test could assess the intragastric Helicobacter pylori load and predict the outcome of infected subjects undergoing short-term triple therapy. METHODS: A total of 108 infected patients underwent upper endoscopy with antral biopsies and histological grading of Helicobacter pylori density. These patients received omeprazole 20 mg b.i.d., clarithromycin 500 mg b.i.d., and amoxycillin 1000 mg b.i.d. or tinidazole 500 mg b.i.d. for one week. 13C-urea breath test (75 mg 13C-urea; results expressed as Delta Over Baseline values at 30') was performed before and after therapy. According to pre-treatment Delta Over Baseline at 30' values, patients were assigned to low (< 16/1000), intermediate (16-35/1000) and high (> 35/1000) Delta Over Baseline at 30' groups. RESULTS: A significant correlation was found between pre-treatment Delta Over Baseline at 30' values and the density of Helicobacter pylori (rs = 0.76). The eradication rates were 82%, 67%, and 17% in the low, intermediate, and high Delta Over Baseline at 30' groups, respectively (p = 0.0001). When classified according to the outcome of therapy, the median pre-treatment Delta Over Baseline at 30' value was 15.7 in eradicated subjects vs 21.6 in non eradicated patients (p = 0.002). In patients who failed eradication, a significant difference was also observed between pre- and post-treatment Delta Over Baseline at 30' values (21.6 vs 15.6, p = 0.019). CONCLUSIONS: The 13C-urea breath test can be used to evaluate the intragastric bacterial load and to predict the outcome of standard eradication treatment.

Adult↗
PubMed1998

13C-octanoic acid breath test: a reliable tool for measuring gastric emptying.

Non-invasive evaluation of gastric emptying is generally performed by scintigraphy which is, however, not always applicable and is not suitable for children and child-bearing women. Recently, a new method based on stable isotope breath testing has been introduced in clinical practice i.e., the 13C-octanoic acid breath test. An overview is made here of the current knowledge on this technique with special emphasis on the principle of the test, the mathematics used to analyse the results, and the physiological, pathological, and pharmacological aspects of gastric emptying studied with this new method. Possible pitfalls of the test are also reported.

Breath Tests↗
PubMed1997

Helicobacter pylori infection and growth delay in older children.

It is thought that Helicobacter pylori infection may influence growth rate in children. The aim of this study was to evaluate the prevalence of H pylori infection in healthy Italian children, and to look for differences in height between infected and non-infected subjects. Two hundred and sixteen children, aged 3 to 14 years, were tested for H pylori infection by 13C-urea breath test. Centile values for height were calculated. Composite indices for socioeconomic class and household crowding were also determined. Forty nine of 216 children (22.7%) were H pylori positive. The prevalence of infection increased with age. Eight of 49 H pylori positive children (16.3%) were below the 25th centile for height, compared with 13 of 167 H pylori negative children (7.8%). This difference became significant in children aged 8.5 to 14 years; in this group (n = 127), eight of 31 infected children (25.8%) were below the 25th centile for height, compared with eight of 96 non-infected children (8.3%). A significant correlation was found between socioeconomic conditions, household crowding, and H pylori status. By using stepwise logistic regression, only the centile value for height was significantly related to H pylori status in older children. Thus H pylori infection was associated with growth delay in older children, poor socioeconomic conditions, and household overcrowding. This finding is consistent with the hypothesis that H pylori infection is one of the environmental factors capable of affecting growth.

Adolescent↗
PubMed1997

Quality control study of H2 breath testing for the diagnosis of carbohydrate malabsorption in Italy. The "Tenue Club" Group.

BACKGROUND AND AIMS: H2 breath testing is increasingly used in Italy. The aim of this multicenter study was to assess the accuracy of this technique in the diagnosis of carbohydrate malabsorption. METHODS: An anonymous questionnaire was used to collect information about H2 breath testing methods and to design the quality control study. Fifteen out of 23 laboratories responded to the questionnaire and 12/23 completed the entire study. RESULTS: The survey revealed that a large variety of H2 testing methods are employed in Italy, but none have been previously tested for accuracy. This prospective study showed that these tests fail to identify > 20% of patients with malabsorption. In contrast, a new method based on single H2 breath measurement at 6 hours after lactulose ingestion and a cutoff value of greater than 5 ppm, had a sensitivity of 92% +/- 4% and a specificity of 94% +/- 0.5%. Increasing the cut-off to 10 ppm resulted in a sensitivity of 88% +/- 9% and a specificity of 100%. This improved accuracy was obtained with a much simpler testing procedure in which only one breath sample is analyzed, in contrast to the baseline and multiple subsequent samples that are analyzed using the currently employed techniques. CONCLUSIONS: A great improvement in the accuracy of the H2 breath test, as well as a considerable saving in terms of time and costs, may be possible through the use of a new, simplified H2 breath test followed by careful H2 analysis.

Breath Tests↗
PubMed1996

Gastric emptying and Helicobacter pylori infection in duodenal ulcer disease.

The pathogenetic link between Helicobacter pylori gastritis and duodenal ulcer is still unknown. Fast gastric emptying of liquids might be important in the pathogenesis of gastric metaplasia of the duodenum and duodenal ulcer through an increased exposure of the duodenum to gastric acid. In H. pylori-infected subjects, an abnormal gastric emptying could affect urea breath test results and correlate with histological gastritis. This study was performed to evaluate the gastric emptying of liquids in duodenal ulcer patients with H. pylori infection and the possible relation between the bacterial load, gastric emptying, and urea breath test results. Seventeen duodenal ulcer patients with H. pylori gastritis and 15 healthy volunteers were studied by a [14C]octanoic acid and [13C]urea breath test to evaluate gastric emptying rate and H. pylori status simultaneously. Endoscopy with antral biopsies were performed in all duodenal ulcer patients. Duodenal ulcer patients with H. pylori infection have a normal liquid gastric emptying that is unrelated with histological severity of gastritis. The urea breath test results and the gastric emptying parameters do not correlate with histology. A significant correlation between the gastric emptying and the urea hydrolysis rate is found. It is concluded that H. pylori infection and duodenal ulcer disease is not associated with abnormally fast liquid gastric emptying, and this finding should be taken into account when a casual link between H. pylori infection and duodenal ulcer disease is searched for. The correlation between gastric emptying and urea hydrolysis rate explains why no conclusions on intragastric bacterial load can be drawn from the urea breath test results.

Adult↗
PubMed1996

Controlled trial of botulinum toxin injection versus placebo and pneumatic dilation in achalasia.

BACKGROUND & AIMS: Intrasphincteric injection of botulinum toxin has been suggested as an alternative treatment modality in esophageal achalasia. A controlled trial comparing botulinum toxin, placebo, and pneumatic dilation is reported. METHODS: Sixteen patients received random intrasphincteric injections of either botulinum toxin or saline. The efficacy of treatment was assessed by symptom score, esophageal manometry, and scintigraphy. In case of failure, pneumatic dilation was performed. RESULTS: One month after injection, symptoms had improved in all patients treated with botulinum toxin (symptom score, 0.9 +/- 0.6 vs. 5.5 +/- 1.4; P < 0.02). In the placebo group, symptoms were unchanged in all patients, who were all dilated. Lower esophageal sphincter pressure decreased by 49% after treatment with botulinum toxin (P < 0.03) and by 72% after dilation (P < 0.01). Similarly, esophageal retention decreased by 47% after treatment with botulinum toxin (P < 0.02) and by 59% after dilation (P < 0.02). No significant difference in symptom score and esophageal function test results was found between patients treated with botulinum toxin injections and those undergoing dilation. However, 7 of the 8 patients in the botulinum toxin group required a second injection because of recurrent dysphagia. CONCLUSIONS: Treatment of achalasia with botulinum toxin was as effective as pneumatic dilation in relieving symptoms and improving esophageal function. The effect of the first injection was temporary, but the effect of the second injection lasted longer.

Adult↗