Influence of 1-week Helicobacter pylori eradication therapy with rabeprazole, clarithromycin, and metronidazole on 13C-aminopyrine breath test

Relationship between 13C-aminopyrine breath test and the MELD score and its long-term prognostic use in patients with cirrhosis

BACKGROUND

(13)C-Aminopyrine breath test ((13)C-ABT) is a non-invasive, dynamic, quantitative liver function test, and the model for end-stage liver disease (MELD) is a recognised biochemical score used to predict survival in patients with cirrhosis.

AIMS

The purpose of this study was to evaluate the relationship between the (13)C-ABT and MELD score in a cohort of cirrhotic patients and, moreover, to assess the prognostic value of (13)C-ABT results in the same group of patients.

PATIENTS AND METHODS

Forty-six patients with cirrhosis and without hepatocellular carcinoma who underwent (13)C-ABT and who had at least 1-year follow-up were prospectively included in this study. MELD score was calculated at entry into the study in all patients. End-points of the study were 1-year liver-related death or liver transplantation.

RESULTS

(13)C-ABT %dose/h at 30 min (%dose/h30) results showed significant, inverse correlation with MELD scores (r = -0.414, P = 0.004). During 1-year follow-up nine patients died (19.6 %) and two were transplanted (4.3 %). Median (13)C-ABT %dose/h30 results (3.2 vs. 1.8) were significantly higher in patients who survived as compared to those who died or underwent transplantation (P = 0.04). Receiver operating characteristics curves showed that a (13)C-ABT %dose/h30 cut-off of 2.0 had the best accuracy (c-index = 0.717) in assessing 1-year prognosis.

CONCLUSIONS

We observed a correlation between a flow-independent quantitative liver function test and the MELD score, and found that the (13)C-ABT may accurately provide long-term prognostic information in cirrhotic patients.

Dissociative disorder induced by clarithromycin combined with rabeprazole in a patient with gastritis

Clarithromycin and rabeprazole are both valued for their safety profile. Very few cases of adverse side-effects related to these drugs, when given individually, have been reported; serious side-effects of clarithromycin in combination with rabeprazole have never been reported. The present case reports on a 51-year-old woman with gastritis who received clarithromycin combined with rabeprazole for Helicobacter pylori infection. After taking 500 mg clarithromycin and 10 mg rabeprazole orally she displayed acute psychotic symptoms of dissociative disorder, including: impairment of orientation and attention; the feeling of dreaming; disintegration of thinking; stereotyped speech; flattened emotion; amnesia. Routine blood investigations, computed tomography scans and electroencephalography showed no abnormalities. All symptoms disappeared without antipsychotic treatment ≈ 48 h after she had taken the two drugs. Combining clarithromycin with rabeprazole might increase the risk of neurotoxicity, particularly in susceptible individuals. This should be a concern in clinical practice.

Influence of different proton pump inhibitors on activity of cytochrome P450 assessed by [(13)C]-aminopyrine breath test

Aminopyrine is metabolized by cytochrome P450 (CYP) in the liver. The investigators evaluated influences of different PPIs on CYP activity as assessed by the [(13)C]-aminopyrine breath test ([(13)C]-ABT). Subjects were 15 healthy volunteers with different CYP2C19 status (5 rapid metabolizers [RMs], 5 intermediate metabolizers [IMs], and 5 poor metabolizers [PMs]). Breath samples were collected before and every 15 to 30 minutes for 3 hours after oral ingestion of [(13)C]-aminopyrine 100 mg on day 8 of each of the following regimens: control; omeprazole 20 mg and 80 mg, lansoprazole 30 mg, and rabeprazole 20 mg. Changes in carbon isotope ratios in carbon dioxide ((13)CO(2)/(12)CO(2)) in breath samples were measured by infrared spectrometry and expressed as delta-over-baseline (DOB) ratios (‰). Mean areas under the curve of DOB from 0 to 3 h (AUC(0-3h) of DOB) were significantly decreased by omeprazole 20 mg and lansoprazole 30 mg but not by rabeprazole 20 mg. Conversely, higher PPI dose (ie, omeprazole 80 mg) seemed to further decrease AUC(0-3h) of DOB in RMs but increased it in PMs. Omeprazole and lansoprazole at the standard doses inhibit CYP activity but rabeprazole does not, whereas high-dose omeprazole seems to induce CYPs.

Monitoring cytochrome P-450 activity during rabeprazole treatment in patients with gastresophageal reflux disease

Proton pump inhibitors (PPIs) are the cornerstone in the treatment of gastresophageal reflux disease (GORD). PPIs are metabolized by the hepatic cytochrome P-450 enzymes (CYP-450). Rabeprazole is a PPI whose metabolism shows fewer interactions compared to other PPIs. In this study we evaluated the influence of rabeprazole administration on hepatic CYP-450 activity as measured by the (13)C-aminopyrine breath test ((13)C-ABT) in a group of patients with GORD. (13)C-ABT was performed on five GORD patients both before and after 1 week of rabeprazole administration (20 mg, b.i.d.). Pretreatment (13)C-ABT results were compared to posttreatment results. Pre- and posttreatment (13)C-ABT results for patients were compared to those obtained in five controls who did the test twice, with a 1-week interval in between. Before treatment, the (13)C-ABT results for the GORD patients did not significantly differ from those of healthy subjects. After treatment, we observed no significant modification of the (13)C-ABT in GORD patients compared to pretreatment values ((13)C-ABT %dose/hr, 10.56+/-1.31 versus 11.17+/-0.88; (13)C-ABT %cumulative dose, 8.08+/-1.11 versus 8.34+/-0.56). Posttreatment (13)C-ABT results were not significantly different from those obtained in controls at weekly repetition of the test. In patients with GORD, 1-week, full-dose rabeprazole does not display any significant interactions with CYP-450 activity.

Can Helicobacter pylori eradication regimens be shortened in clinical practice? An open-label, randomized, pilot study of 4 and 7-day triple therapy with rabeprazole, high-dose levofloxacin, and tinidazole

BACKGROUND

Rabeprazole is a proton pump inhibitor which is particularly suitable for use in short-term Helicobacter pylori eradication treatment. Levofloxacin-based H. pylori eradication regimens have shown good efficacy and very few side effects. Shorter treatment and absence of significant side effects should improve compliance to therapy and increase the Hp H. pylori eradication rate.

AIMS

To evaluate the effectiveness of 2 rabeprazole-based H. pylori eradication regimens in an open-label, randomized study carried out in a clinical practice setting.

METHODS

One hundred sixty-nine consecutive, treatment-naive patients with H. pylori infection were randomized to receive rabeprazole (20 mg, bid), levofloxacin (500 mg, bid), and tinidazole (500 mg, bid) for either 4 [4-d rabeprazole, levofloxacin, tinidazole (RLT), n=85] or 7 days (7-d RLT, n=84). Before treatment, all patients underwent upper digestive endoscopy. Cure rates were assessed by means of C-urea breath test. and were compared with the eradication rate obtained with standard triple therapy in our Unit (ie, 78%) and average eradication rate reported in the literature (ie, 79%).

RESULTS

The intention-to-treat eradication rates were 94% [87% to 98%, 95% confidence interval (CI)] and 95% (88% to 99%, 95% CI) in the 4-day RLT and 7-day RLT regimens, respectively, whereas per-protocol eradication rates were 95% (88% to 99%, 95% CI) in the 4-day RLT and 96% (90% to 99%, 95% CI) in the 7-day RLT. Both treatment regimens obtained significantly higher eradication rates as compared with standard triple therapy. The 4-day RLT showed significantly fewer side effects.

CONCLUSIONS

In a clinical practice setting, both 4-day and 7-day rabeprazole, high-dose levofloxacin, tinidazole-based regimens achieved relevant H. pylori eradication rates in treatment-naive patients. The lower number of side effects makes the shorter treatment regimen preferable over the conventional 7-day treatment.

A study of 4- and 7-day triple therapy with rabeprazole, high-dose levofloxacin and tinidazole rescue treatment for Helicobacter pylori eradication

BACKGROUND

Helicobacter pylori treatment failure is becoming an emergent problem in clinical practice. Shorter treatment duration should improve compliance to therapy and keep an acceptable H. pylori eradication rate.

AIMS

To evaluate the efficacy of two rabeprazole, high-dose levofloxacin and tinidazole-based regimens as 'rescue' treatment for H. pylori eradication in an open-label, randomized, pilot study carried out in a clinical practice setting.

METHODS

Eighty-five consecutive patients who have previously failed at least one H. pylori eradication attempt were randomized to receive rabeprazole (20 mg, b.d.), levofloxacin (500 mg, b.d.) and tinidazole (500 mg, b.d.) either for 4 (4-day RLT, n = 42) or 7 days (7-day RLT, n = 43). Cure of H. pylori infection was assessed by means of 13C-urea breath test.

RESULTS

The 7-day RLT achieved 84% (95% CI: 69-93%) and 86% (95% CI: 72-95%) eradication rates in intention-to-treat and per-protocol analyses respectively. The shorter treatment obtained an 83% (95% CI: 69-93%) eradication rate in both intention-to-treat and per-protocol analysis. Both regimens were well tolerated, although patients who received the 4-day RLT reported fewer side-effects.

CONCLUSIONS

In patients who have previously failed at least one H. pylori eradication attempt, both 4- and 7-day rabeprazole, high-dose levofloxacin, tinidazole-based regimens are effective in curing the infection in more than 80% of patients.