Patrizia Scalabrini

Spontaneous noncardiac chest pain: Value of ambulatory esophageal pH and motility monitoring

We performed esophageal investigations in 20 patients suffering from noncardiac chest pain in order to assess the diagnostic value of short-versus long-term manometric and pH studies. Patients had baseline esophageal manometry with two provocative tests: a Bernstein test and an intravenous injection of edrophonium. On a separate occasion they had a 24-hr ambulatory esophageal pH and motility recording. The Bernstein test provoked chest pain in two patients, while edrophonium injection did not elicit pain in any of the patients. The ambulatory pH study helped to establish the esophagus as the likely source of pain in one patient, and the ambulatory motility one in another. In our experience, ambulatory pH and motility recordings have a low diagnostic yield in the evaluation of patients with noncardiac chest pain.

Is hepatic ultrasonography a valid alternative tool to liver biopsy? report on 507 cases studied with both techniques

In order to evaluate the diagnostic potential of liver ultrasonography (US), the charts of 23 cases with normal liver, 424 patients with chronic widespread, and 60 patients with focal hepatic diseases, who had undergone both US and liver biopsy, were reviewed. The positive predictive value of US was good in all hepatic disorders (range 86.9–96.5%), while its negative predictive value was very low (range 14.1–42.5%) in the various forms of widespread liver disease and suitable for screening purposes (74%) in focal lesions. Of the 507 cases, 39 with an ultrasonically suspected liver mass also underwent an echo-guided fine-needle aspiration, which showed a high sensitivity (85%) in the 27 biopsy-proved malignant lesions and excluded tumor cells in the remaining 12 cirrhotic cases. As regards US tissue diagnosis, hepatic tumors, fatty infiltration, and fibrosis were detected in 88%, 60%, and 49% of cases, respectively. Fat and fibrous content on biopsy were similarly and significantly correlated with both echo pattern and sound attenuation. Overall results suggest that in the group of widespread hepatic disorders the usefulness of US is greatly reduced by the fact that the patients actual condition is not likely to be negative if US examination is normal and by the impossibility of differentiating fat from fibrosis. In focal lesions, the diagnostic value of US appears high and the method may frequently provide conclusive proof of the tumor if a positive cytodiagnosis on echoguided aspirated material is done.

24-hour study of intragastric acidity in duodenal ulcer patients and normal subjects using continuous intraluminal pH-metry

The circadian pattern of intragastric acidity was assessed in 19 healthy subjects and 37 patients with active, endoscopically proven duodenal ulcer using 24-hr continuous intraluminal pH-metry. The median pH 24-hr profiles showed that ulcer patients had lower postprandial pH elevations and a smaller decline in acidity during the early morning hours when compared with controls. The after-lunch and -dinner area under the curve and maximum pH values were significantly higher in controls compared to ulcer patients. In the nighttime, the median pH values in controls were significantly higher during 9 pm to 12 pm (P=0.02), 12 pm to 4 am P=0.01), and 4 am to 8 am (P=0.0008) compared to the ulcer patients. We conclude that the 24-hr acidity is higher in ulcer patients compared to healthy subjects and that the differences are particularly evident in the postprandial and nocturnal periods.

24-H comparison between pH values of continuous intraluminal recording and simultaneous gastric aspiration.

This study was undertaken to show whether the correlation between pH values indicated by an intraluminal pH electrode and those simultaneously recorded for gastric aspirates is not only linear but also proportional, so that the two measurement techniques can be considered alternative. A 24-h intragastric pH-monitoring with an antimony electrode, to which a nasogastric tube for hourly aspiration of gastric juice was closely attached, was performed on 20 duodenal ulcer patients. Our data show that the slope of the straight line related to 335 pH pairs is virtually equal to 1, whereas the elevation is almost equal to zero, and this result strongly suggests that a proportional relationship exists between intragastric and aspirate pH levels throughout the whole 24-h period. Besides, in the majority of cases (81%) the pH pairs differ by no more than 1 pH unit. It can be concluded that these two pH monitoring methods may be alternative.

Comparison of the Effects of Placebo, Ranitidine, Famotidine and Nizatidine on Intragastric Acidity by Means of Continuous pH Recording

The effects of single daily doses of placebo, nizatidine 300 mg, ranitidine 300 mg and famotidine 40 mg, given at 22.00 h, have been compared in 16 patients with healed duodenal ulcers. Each of them underwent the above treatment on four separate occasions. The three H2 receptor antagonists showed a significantly higher acid inhibition than placebo (p less than 0.003) throughout the whole 24-hour period. Famotidine turned out to be more effective than nizatidine (p less than 0.02) in reducing circadian acidity, while there was no difference between ranitidine and nizatidine. The effects of the three H2 blockers on overnight acidity (from 23.00 to 07.00) were similar to each other, whereas both famotidine (p less than 0.003) and ranitidine (p less than 0.02) produced more anacidity than nizatidine during the morning hours (from 07.00 to 12.00). The time period elapsed in consecutive minutes above 5.0 pH units during drug-related events was significantly longer with both famotidine (p less than 0.01) and ranitidine (p less than 0.01) compared to nizatidine. Therefore in the recommended dosages for clinical use the acid suppression of nizatidine was significantly shorter-lasting than that of both ranitidine and famotidine. The major change is represented by the lack of carryover effect of nizatidine on morning acidity.

Continuous 24-hour intragastric pH monitoring in the evaluation of the effect of a nightly dose of famotidine, ranitidine and placebo on gastric acidity of patients with duodenal ulcer.

In 11 duodenal ulcer patients, the antisecretory effects of bedtime famotidine 40 mg were compared to those obtained with ranitidine 300 mg and placebo by means of continuous 24-hour intragastric pH monitoring. The 24-hour areas under the curve of pH profiles of the two H2 blockers were significantly different from those related to placebo (p approximately 0 for ranitidine and p = 0.00001 for famotidine), but not from each other (p = 0.51). Onset and duration of the famotidine action, however, were respectively earlier and longer lasting (12 vs. about 9 h) than those of ranitidine. Famotidine was also significantly superior (p approximately 0) to ranitidine in keeping intragastric pH at high values (especially those comprised between 6 and 8 pH units), although theoretically equipotent doses of the two H2 antagonists were used.

Once and Twice Daily Doses of H2 Antagonists Revisited, Using Continuous Intragastric pH Monitoring

Eight patients with previous duodenal ulcer in symptomatic remission underwent continuous intraluminal pH monitoring on five separate occasions to compare the effects on 24-h intragastric acidity of placebo, 300 mg ranitidine at night, 150 mg ranitidine twice daily, 40 mg famotidine at night, and 20 mg famotidine twice daily. All H2 blocker treatments were superior to placebo (p congruent to 0), whereas the twice daily doses of both ranitidine and famotidine were significantly better (p congruent to 0 and p = 0.00006, respectively) than the single ones in reducing 24-h intragastric acidity. The higher acid inhibitory effect of the twice daily dose regimens than of the single ones was evident during the daytime, whereas no difference between them was found during the nighttime (from 2200 to 0800 h). These data are at variance with those previously published, and the slight effect of the single nightly doses of H2 blockers on daytime acidity seems to confirm further that the suppression of nocturnal acidity may really be the decisive factor in the success of this dosing schedule in treating duodenal ulcer.

Evaluation of antisecretory activity of misoprostol in duodenal ulcer patients using long-term intragastric pH monitoring

The effect of the new synthetic prostaglandin E1analog, misoprostol, on intragastric acidity was evaluated by means of 24-hr intraluminal pH monitoring of 16 duodenal ulcer patients. They were randomly allocated into two groups: eight received no medication and misoprostol 400 Μg bid and eight received ranitidine 150 mg and misoprostol 400 Μg bid not less than one week apart. The comparison of the 24-hr areas under the curve related to the median pH values showed that no difference existed between misoprostol and untreated patients in the first group, while ranitidine was significantly more effective (P= 0.00003) than misoprostol in the second group. The analysis of arithmetic differences between the 24-hr median pH values showed that misoprostol increased pH values by at least one unit compared to the untreated subgroup for about 3.5 hr, while the antisecretory action of ranitidine was far superior to that of misoprostol throughout the whole 24-hr period. It can be concluded that the effect of twice daily doses of misoprostol 400 Μg on 24-hr intragastric pH is small and not at all comparable to that of the well-known potent H2blocker ranitidine.

Single Bedtime Dose of Famotidine: Assessment of Its Antisecretory Action by 24-Hour Intragastric pH Monitoring

The antisecretory efficacy of a single bedtime dose of famotidine, a new potent H2‐receptor antagonist, was evaluated by means of continuous 24‐hour intragastric pH monitoring. Of 20 patients with duodenal ulcers, ten randomly received famotidine 40 mg at 10 PM and ten were monitored without medication for control. Famotidine regimen led to a remarkable reduction of gastric acidity in patients who were treated for duodenal ulcer and the drug‐induced pH levels were significantly different (P < .0001) from those of untreated controls. The antisecretory action lasted for 12 hours, which comprised the nocturnal period, whereas no important difference was found between the two groups for the most part of the daytime. The drug was able to keep intragastric pH above 4 units during almost 50% of the whole 24‐hour period. These results confirm that famotidine is a powerful and long‐acting H2 blocker that relieves gastric acidity during the night and morning hours when administered as a single bedtime dose of 40 mg.

A comparison of the effects on intragastric acidity of bedtime or dinnertime administration of a once daily dose of famotidine

SummaryIn order to assess whether dinnertime administration of a once daily dose of famotidine is more advantageous than a bedtime dose in suppressing evening and nocturnal gastric acidity, we gave nine patients with a past history of duodenal ulcer in double-blind, randomized fashion either (1) placebo at 6 p.m. and 10 p.m., (2) famotidine 40 mg at 6 p.m. (Fam 6) + placebo at 10 p.m. or (3) placebo at 6 p.m. + famotidine at 10 p.m. (Fam 10) on three separate occasions.Comparison of the 24-h median pH values showed that the two administrations of famotidine were superior to placebo, while Fam 6 was significantly more effective than Fam 10. The gain in acid suppression of Fam 6 with respect to Fam 10 was particularly evident from 6 p.m. to midnight.Although the antisecretory effectiveness of Fam 6 was lower than that of Fam 10 from 4 a.m. to 8 a.m., it remained clearly higher than that of placebo and ensured virtual anacidity (median pH=6.7) even in this time segment.We conclude that a once daily dose of famotidine at 6 p.m. is better than bedtime administration at covering the long period of continuous unbuffered intragastric acidity which extends from after the evening meal to breakfast.