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J M Pajares

Publications and source records attributed to J M Pajares.

At least 37 records · Page 2Linked to original sources
PubMed2003

Meta-analysis: proton pump inhibitors vs. H2-receptor antagonists--their efficacy with antibiotics in Helicobacter pylori eradication.

BACKGROUND: It is unknown whether proton pump inhibitors are superior to H2-receptor antagonists in Helicobacter pylori eradication regimens. AIM: To perform a meta-analysis comparing the efficacy of both antisecretors when co-prescribed with antibiotics. METHODS: Randomized clinical trials comparing proton pump inhibitors vs. H2-receptor antagonists with the same antibiotics were selected. Data sources included PubMed, the Cochrane Controlled Trials Register and abstracts from congresses up to January 2002. A meta-analysis was performed by combining the odds ratios. RESULTS: Twenty studies fulfilled the inclusion criteria. In the intention-to-treat analysis, the mean eradication rates with proton pump inhibitors and H2-receptor antagonists plus antibiotics were 74% [95% confidence interval (CI), 71-76%] and 69% (95% CI, 66-71%), respectively. The odds ratio for this comparison was 1.31 (95% CI, 1.09-1.58). The number needed to treat with proton pump inhibitors to achieve eradication success, compared with H2-receptor antagonists, was 25. When studies prescribing very high doses of H2-receptor antagonists (two of the outliers) were excluded, the odds ratio (for proton pump inhibitors vs. H2-receptor antagonists) increased to 1.37, the number needed to treat decreased to 20 and the heterogeneity between the studies decreased. CONCLUSIONS: Overall, proton pump inhibitors are more effective than H2-receptor antagonists when prescribed at usual doses with antibiotics to eradicate H. pylori infection.

Anti-Bacterial Agents↗
PubMed2003

Systematic review: Rabeprazole-based therapies in Helicobacter pylori eradication.

AIM: To perform a systematic review of the efficacy of rabeprazole-based therapies in Helicobacter pylori eradication, and to conduct a meta-analysis comparing the efficacy of rabeprazole and other proton pump inhibitors when co-prescribed with antibiotics. METHODS: Studies evaluating rabeprazole plus antibiotics were considered. Only randomized trials comparing rabeprazole and other proton pump inhibitors with antibiotics, and differing only in the proton pump inhibitor, were included in the meta-analysis. Electronic and manual bibliographic searches were conducted. The percentage (weighted mean) of successful eradication was calculated. Meta-analysis was performed by combining the odds ratios (OR) of the individual studies. RESULTS: The eradication rates were as follows: 14-day rabeprazole-amoxicillin, 73%; rabeprazole-amoxicillin-clarithromycin for 3, 5, 7 and 10 days, 44%, 72%, 78% and 75%, respectively; low-dose rabeprazole (20 mg/day), amoxicillin and clarithromycin for 7 days, 81%; high-dose rabeprazole (40 mg/day), amoxicillin and clarithromycin for 7 days, 75%; 7-day rabeprazole-clarithromycin-nitroimidazole, 85%. Twelve comparative studies were included in the meta-analysis. The eradication rate with rabeprazole plus antibiotics was 79%; it was 77% with other proton pump inhibitors (OR = 1.15; 95% confidence interval, 0.93-1.42). Sub-analysis comparing rabeprazole at low doses (10 mg b.d.) with other proton pump inhibitors at standard doses (omeprazole 20 mg b.d. or lansoprazole 30 mg b.d.) showed no differences. CONCLUSIONS: Rabeprazole achieves similar H. pylori eradication rates to omeprazole and lansoprazole when co-prescribed with antibiotics. Low doses of rabeprazole (10 mg b.d.), when administered with two antibiotics, may be sufficient to eradicate H. pylori infection.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

[Comparison between two 13C-urea breath tests for the diagnosis of Helicobacter pylori infection: isotope ratio mass spectrometer versus infrared spectrometer].

OBJECTIVES: To compare the accuracy of the breath test using the isotope ratio mass spectrometer (IRMS) versus the nondispersive isotope-selective infrared spectrometer (NDIRS) in the diagnosis of Helicobacter pylori infection. METHOD: Multicenter study in 4 Spanish hospitals. One group of dyspeptic patients who had not undergone prior eradication therapy and another group of patients with gastric ulcer or gastrointestinal bleeding due to gastroduodenal ulcer receiving H. pylori eradication therapy were included in the study. A reference standard based on histology and the rapid urease test was used. The breast test (TAU-KIT, Isomed S.L., Madrid, Spain) was performed with citric acid and 100 mg of 13C-urea. Samples of expired air were collected in tubes and bags for reading with the IRMS (ABCA, PDZ, Crewe, Manchester, England) and the NDIRS (UBiT-IR200, Otsuka Electronics, Co, Osaka, Japan), respectively. The endoscopist, pathologist and person responsible for reading the urease test and both breath tests were blinded to the results of the other diagnostic methods. RESULTS: Forty-one patients were included. The prevalence of H. pylori was 26%. No differences were found on comparing the mean values obtained with the IRMS and the NDIRS: 13 (standard deviation) (24) and 14 (25) delta units, respectively. The area under the ROC curve for the IRMS and the NDIRS was 0.96. The diagnostic accuracy for the best cut-off point with the IRMS and the NDIRS was, respectively: sensitivity (90 and 100%), specificity (96 and 89%), positive predictive value (90 and 77%), negative predictive value (96 and 100%), + likelihaod ratio (25 and 9.3) and (0.1 and 0). A close correlation was found between the values of the IRMS and those of the NDIRS (lineal regression equation, Y = 1.1 + 1.004. X; r = 0.97). CONCLUSION: Both the spectrometers used to evaluate the breath test, the IRMS and the NDIRS, offer a high degree of accuracy in the diagnosis of H. pylori infection.

Breath Tests↗
PubMed2003

Review article: is there an optimal therapeutic regimen for antimitochondrial antibody-negative primary biliary cirrhosis (autoimmune cholangitis)?

Testing for antimitochondrial antibodies is the most useful laboratory procedure in the diagnosis of primary biliary cirrhosis; nevertheless, 5-10% of patients with typical features of primary biliary cirrhosis do not have detectable antimitochondrial antibodies, their condition being referred to as antimitochondrial antibody-negative primary biliary cirrhosis or "autoimmune cholangitis". Uncertainty exists whether antimitochondrial antibody-positive and -negative primary biliary cirrhosis represent distinct entities. We reviewed studies that compared: (i) the clinical, laboratory and histological characteristics of antimitochondrial antibody-positive and -negative primary biliary cirrhosis; (ii) the response to treatment of both conditions; and (iii) the response of autoimmune cholangitis to ursodeoxycholic acid and immunosuppressive therapy. Antimitochondrial antibody-positive and -negative primary biliary cirrhosis were characterized by similar clinical, laboratory and histological abnormalities, clinical course and survival. Antimitochondrial antibody status did not seem to affect the response to ursodeoxycholic acid. At present, the efficacy of therapies for autoimmune cholangitis has not been established in controlled trials. Of 52 patients with autoimmune cholangitis treated with ursodeoxycholic acid in 13 uncontrolled studies, 83% had serum biochemical improvement. Also, a favourable effect of immunosuppressive drugs occurred in 57% of 54 patients with autoimmune cholangitis in 17 uncontrolled studies. Each of these trials included very few patients and most evaluated the effects of treatment on surrogate markers of disease only. No marker that consistently distinguished patients who would respond favourably to ursodeoxycholic acid or immunosuppression was apparent. Consequently, treatment is, at present, empirical. However, ursodeoxycholic acid may be given when histology reveals bile duct lesions, whereas immunosuppressive therapy should probably be reserved for patients exhibiting interface hepatitis.

Antibodies↗
PubMed2003

Attitude facing a patient suffering from Helicobacter pylori infection resistant to a triple therapy.

Even with the current most effective treatment regimens, about 10-20% of patients will fail to eradicate H. pylori infection. Therefore, in designing a treatment strategy we should not focus on the results of primary therapy alone, but also on the final (over-all) eradication rate. The choice of a second-line treatment depends on which treatment was used initially, as retreatment with the same regimen is not recommended. In this respect, the first therapy should not be a regimen that combines clarithromycin and metronidazole in the same regimen, because of the problem of resistance against both antibiotics. Therefore, it seems that performing culture after a first eradication failure is not necessary and assessing H. pylori sensitivity to antibiotics only after failure of the second treatment may be suggested in clinical practice. Different possibilities of empirical treatment are suggested. After failure of proton pump inhibitor (PPI)-amoxicillin-clarithromycin, quadruple therapy has been generally used. More recently, replacing the PPI and the bismuth compound by ranitidine bismuth citrate (RBC) has also achieved good results. After PPI-amoxicillin-nitroimidazole failure, retreatment with PPI-amoxicillin-clarithromycin has proved to be effective. Finally, rifabutin-based rescue therapies have shown to constitute an encouraging strategy for eradication failures, as they are effective for H. pylori strains resistant to antibiotics.

Anti-Bacterial Agents↗
PubMed2003

Validation of the 13c-urea breath test for the initial diagnosis of helicobacter pylori infection and to confirm eradication after treatment.

OBJECTIVES: the breath test with 13C-urea (UBT) is a method widely used in Spain, but its diagnostic accuracy has not been evaluated in a clinical trial until now. Our objective was to validate the UBT (TAU-KIT) both as an initial diagnostic method for the detection of H. pylori infection and as a method to confirm eradication. METHODS: a multi-centre study in 7 Spanish hospitals was performed. A group of dyspeptic patients who had not previously received eradication treatment was included, and a second group of patients with gastric ulcer or upper gastrointestinal bleeding due to peptic ulcer was also included (eradication of H. pylori was confirmed 6 to 8 weeks after treatment completion with omeprazole, clarithromycin and amoxycillin). In both groups an endoscopy was performed with biopsies for histology and rapid urease test. Patients were considered infected if both tests yielded positive results, and not infected when both tests were negative. The UBT 13C-urea (TAU-KIT, Isomed S.L., Madrid, Spain) was performed with citric acid and 100 mg of 13C-urea. The pathologist and persons responsible for endoscopy, urease test and UBT were all unaware of the results from the other diagnostic methods. RESULTS: in the pre-treatment group (36 patients) the prevalence of H. pylori was 72%, the area under the ROC curve for the diagnosis of infection with the UBT was 0.99, and the best cut-off point was 5 units, with the following results: sensitivity= 96% (95% CI = 81-99%), specificity= 100% (69-100%), positive predictive value (PPV) = 100% (87-100%), negative predictive value (NPV) = 92% (59-100%), likelihood ratio (LR) + = infinity, and LR- = 0.04. In the post-treatment group (85 patients) the prevalence of H. pylori was 16%, the area under the ROC curve was 0.99, and the best cut point was 4.6, with the following results: sensitivity= 100% (77-100%), specificity = 97% (90-99%), PPV = 88% (62-98%), NPV = 100% (95-100%), LR+ = 35, and LR- = 0. CONCLUSION: UBT provides excellent accuracy both for the initial diagnosis of H. pylori infection and to confirm eradication after treatment.

Adult↗
PubMed2002

[Study of the validity of "rapid" serology in diagnosing Helicobacter pylori infection].

OBJECTIVE: To evaluate prospectively the validity of a < > serology diagnosis method (using capillary blood) in our ambit, taking for reference a combination of standard diagnostic methods. DESIGN: Prospective. The endoscopist, pathologist and those responsible for interpreting the rapid urease test, the breath test and < > serology did not know the results of the other diagnostic methods. SETTING: Gastro-enterology service of a tertiary hospital.Participants. 30 consecutive patients with symptoms attributable to the upper digestive tract and who underwent an oral gastroscopy. Main measurements. Gastric biopsies for histology examination and for the rapid urease test and a breath test with 13C-urea were conducted. For < > serology, the commercial SureStep HP WB test kit was used. A patient was considered infected when at least two of the three validated techniques (rapid urease test, histology, breath test) were positive; and not infected, when all three were negative. RESULTS: 30 patients, 30% male, with a mean age of 51, were included. The reference standard indicated 61% prevalence of infection, with two cases classed as undetermined. < > serology was positive in 8 patients and negative in 22. Sensitivity, specificity, positive predictive value and negative predictive value were, respectively, 41% (95% CI, 18-65), 91% (74-100), 87% (65-100) and 50% (28-72). The positive probability quotient was 4.5; and the negative, 0.65. CONCLUSION: The < > serology used in the current study has deficient diagnostic accuracy. Therefore, it should not be used in clinical practice to identify H. pylori infection.

Antibodies, Bacterial↗
PubMed2002

Review article: Helicobacter pylori infection and gastric outlet obstruction - prevalence of the infection and role of antimicrobial treatment.

The prevalence of Helicobacter pylori infection in peptic ulcer disease complicated by gastric outlet obstruction seems to be, overall, lower than that reported in non-complicated ulcer disease, with a mean value of 69%. However, H. pylori infection rates in various studies range from 33% to 91%, suggesting that differences in variables, such as the number and type of diagnostic methods used or the frequency of non-steroidal anti-inflammatory drug intake, may be responsible for the low prevalence reported in some studies. The resolution of gastric outlet obstruction after the eradication of H. pylori has been demonstrated by several studies. It seems that the beneficial effect of H. pylori eradication on gastric outlet obstruction is observed early, just a few weeks after the administration of antimicrobial treatment. Furthermore, this favourable effect seems to remain during long-term follow-up. Nevertheless, gastric outlet obstruction does not always resolve after H. pylori eradication treatment and an explanation for the failures is not completely clear, non-steroidal anti-inflammatory drug intake perhaps playing a major role in these cases. Treatment should start pharmacologically with the eradication of H. pylori even when stenosis is considered to be fibrotic, or when there is some gastric stasis. In summary, H. pylori eradication therapy should be considered as the first step in the treatment of duodenal or pyloric H. pylori-positive stenosis, whereas dilation or surgery should be reserved for patients who do not respond to such medical therapy.

Anti-Bacterial Agents↗
PubMed2002

Review article: Helicobacter pylori "rescue" regimen when proton pump inhibitor-based triple therapies fail.

Even with the currently most effective treatment regimens, about 10-20% of patients will fail to obtain eradication of Helicobacter pylori infection. Therefore, in designing a treatment strategy, we should not focus on the results of primary therapy alone, but also on the final (overall) eradication rate. The choice of second-line treatment depends on which treatment was used initially, as re-treatment with the same regimen is not recommended. Therefore, it is not necessary to perform culture after the first eradication failure. Assessment of the sensitivity of H. pylori to antibiotics only after failure of the second treatment is suggested in clinical practice. Different possibilities of empirical treatment have been suggested. After failure of proton pump inhibitor-amoxicillin-clarithromycin, quadruple therapy has generally been used. More recently, replacement of the proton pump inhibitor and the bismuth compound by ranitidine bismuth citrate has also achieved good results. After proton pump inhibitor-amoxicillin-nitroimidazole failure, re-treatment with proton pump inhibitor-amoxicillin-clarithromycin has been proven to be effective. Finally, first-line treatment should not combine clarithromycin and metronidazole in the same regimen, because of the problem of resistance to both antibiotics. Recently, rifabutin-based rescue therapies have been shown to constitute an encouraging strategy for eradication failures, as they are effective against H. pylori strains resistant to antibiotics.

Amoxicillin↗
PubMed2001

Helicobacter pylori "test-and-scope" strategy for dyspeptic patients. Is it useful and safe?

AIM: To evaluate outcome of test-and-scope strategy using 13C-urea breath test, Helicobacter pylori IgG serology, and CagA serology. PATIENTS AND METHODS: A series of 100 dyspeptic patients were studied. Biopsies were obtained for histology and rapid urease test (gold standard). Serum samples were obtained for Helicobacter pylori IgG and CagA serology, and 13C-urea breath test was carried out. RESULTS: If endoscopy had not been performed in Helicobacter pylori patients based on 13C-urea breath test, <45 years, without alarm symptoms, and without non-steroidal anti-inflammatory drug use, 15% of endoscopies would have been saved, and one gastric ulcer and two oesophagitis would have been missed. Based on Helicobacter pylori IgG serology, 21% of endoscopies would have been saved. Finally, if endoscopy had been performed only in CagA+ patients, 31% of endoscopies would have been saved, missing one gastric ulcer and two cases of oesophagitis. CONCLUSIONS: In our geographical area, the test-and-scope strategy based on 13C-urea breath test or Helicobacter pylori IgG serology would have saved only 15-20% of endoscopies. Although some relevant pathology would have been missed, it is not of a malignant type. 13C-urea breath test is the preferred non-invasive method to be used in this strategy, while Helicobacter pylori IgG serology is of limited value due to its low accuracy. With the use of CagA serology a larger number of unnecessary endoscopic examinations can be avoided.

Adult↗
PubMed2001

Proton pump inhibitors versus H2-antagonists: a meta-analysis of their efficacy in treating bleeding peptic ulcer.

PURPOSE: To evaluate whether proton pump inhibitors are more effective than H2-antagonists (H2-A) for the treatment of bleeding peptic ulcer. DATA SOURCES: PubMed database until January 2000. STUDY SELECTION: Comparative randomized trials of proton pump inhibitors (omeprazole, lansoprazole, or pantoprazole) vs. H2-A (cimetidine, ranitidine or famotidine). DATA EXTRACTION: Meta-analysis combining the odds ratios (OR) of the individual studies in a global OR (Peto method). OUTCOMES EVALUATED: Persistent or recurrent bleeding, need for surgery, or mortality. DATA SYNTHESIS: Eleven studies fulfilled the inclusion criteria and contained data for at least one of the planned comparisons. Persistent or recurrent bleeding was reported in 6.7% (95% CI: 4.9-8.6%) of the patients treated with proton pump inhibitors, and in 13.4% (95% CI: 10.8-16%) of those treated with H2-A (OR 0.4; 95% CI: 0.27-0.59) (chi2-homogeneity test, 18; P=0.09). Surgery was needed in 5.2% (95% CI: 3.4-6.9%) of the patients treated with proton pump inhibitors, and in 6.9% (95% CI: 4.9-8.9%) of the patients treated with H2-A (OR 0.7; 95% CI: 0.43-1.13). Respective percentages for mortality were 1.6% (95% CI: 0.9-2.9%) and 2.2% (95% CI: 1.3-3.7%) (OR 0.69; 95% CI: 0.31-1.57). SUB-ANALYSIS: Five studies evaluated the effect of both therapies given in bolus injections on persistent or recurrent bleeding rate, which was 6% (95% CI: 3.6-8.3%) and 8.1% (95% CI: 5.3-10.9%), respectively (OR, 0.57; 95% CI: 0.31-1.05). Persistent or recurrent bleeding in high risk patients (Forrest Ia, Ib and IIa) occurred in 13.2% (95% CI: 7.9-8%) of the patients treated with proton pump inhibitors and in 34.5% (27-42%) of those treated with H2-A (OR 0.28; 95% CI: 0.16-0.48). In patients not having endoscopic therapy, persistent or recurrent bleeding was reported, respectively, in 4.3% (95% CI: 2.7-6.7%) and in 12% (95% CI: 8.7-15%) (OR 0.24; 95% CI: 0.13-0.43). Less marked differences were observed in patients having adjunct endoscopic therapy: 10.3% (95% CI: 6.7-13.8%) and 15.2% (11.1-19.3%) (OR 0.59; 95% CI: 0.36-0.97). Moreover, the significance disappeared in this group when a single outlier study was excluded. CONCLUSIONS: Proton pump inhibitors are more effective than H2-A in preventing persistent or recurrent bleeding from peptic ulcer, although this advantage seems to be more evident in patients not having adjunct sclerosis therapy. This beneficial effect seems to be similar or even more marked in patients with Forrest Ia, Ib or IIa ulcers. However, proton pump inhibitors are not more effective than H2-A for reducing surgery or mortality rates. Nevertheless, the data are too scarce and heterogeneous to draw definitive conclusions, and further comparative trials are clearly warranted.

Anti-Ulcer Agents↗