Fecal concentration of intravenous vancomycin preparation after oral administration in an experimental model: preclinical assay.

INTRODUCTION: Clostridioides difficile (C. difficile) infection is the main cause of nosocomial diarrhea. First-line treatment is oral vancomycin, but that presentation is not commercially available in Latin America. Our aim was to determine the fecal concentration of the oral administration of the conventional dose of an intravenous vancomycin preparation (VCM), in an experimental model. METHODS: A preclinical trial was conducted on 18 male mice (Balb/c strain), in three batches. The following doses of VCM were administered: 125 mg in batch A; 500 mg in batch B; and VCM-placebo in batch C. After receiving the doses, the mice were placed in metabolic cages, by batch. Feces were collected and the fecal concentration of VCM was analyzed through high pressure liquid chromatography 2, 4 and 6 h after drug administration. RESULTS: The 125 mg dose of VCM reached the minimum inhibitory concentration (MIC) for C. difficile, without reaching the minimum bactericidal concentration (MBC90), at 2, 4, and 6 h (521, 688, and 280 mg/L, respectively). Likewise, the 500 mg dose of VCM reached the MIC at 2 h, increased gradually, and reached MBC90 between 4 and 6 h, in feces (1,062 and 1,779 mg/L, respectively), ANOVA, p = 0.0005. CONCLUSION: The fecal concentration of vancomycin was dependent on the intragastric dose administered. Only the 500 mg dose of VCM reached therapeutic concentration for C. difficile (MIC and MBC90), in the mice. We suggest starting a dose of 500 mg QID for achieving therapeutic concentration against C. difficile, as soon as 4 h after the first dose.

The fourth Mexican consensus on Helicobacter pylori. / IV consenso mexicano sobre Helicobacter pylori.

Important advances have been made since the last Mexican consensus on the diagnosis and treatment of Helicobacter pylori (H. pylori) infection was published in 2007. Therefore, the Asociación Mexicana de Gastroenterología summoned 20 experts to produce "The Fourth Mexican Consensus on Helicobacter pylori". From February to June 2017, 4 working groups were organized, a literature review was performed, and 3 voting rounds were carried out, resulting in the formulation of 32 statements for discussion and consensus. From the ensuing recommendations, it was striking that Mexico is a country with an intermediate-to-low risk for gastric cancer, despite having a high prevalence of H. pylori infection. It was also corroborated that peptic ulcer disease, premalignant lesions, and histories of gastric cancer and mucosa-associated lymphoid tissue lymphoma should be considered clear indications for eradication. The relation of H. pylori to dyspeptic symptoms continues to be controversial. Eradication triple therapy with amoxicillin, clarithromycin, and a proton pump inhibitor should no longer be considered first-line treatment, with the following 2 options proposed to take its place: quadruple therapy with bismuth (proton pump inhibitor, bismuth subcitrate, tetracycline, and metronidazole) and quadruple therapy without bismuth (proton pump inhibitor, amoxicillin, clarithromycin, and metronidazole). The need for antimicrobial sensitivity testing when 2 eradication treatments have failed was also established. Finally, the promotion of educational campaigns on the diagnosis and treatment of H. pylori for both primary care physicians and the general population were proposed.

Clinical assessment and health-related quality of life in patients with non-cardiac chest pain.

INTRODUCTION: Non-cardiac chest pain (NCCP) is mainly related to oesophageal disease, and in spite of being a common condition in Mexico, information regarding it is scarce. AIM: To assess the clinical characteristics and health-related quality of life of patients with NCCP of presumed oesophageal origin. MATERIAL AND METHODS: Patients with NCCP of presumed oesophageal origin with no previous treatment were included in the study. Associated symptoms were assessed and upper gastrointestinal endoscopy and 24-hour oesophageal pH monitoring were performed to diagnose gastroesophageal reflux disease, while oesophageal manometry was used to determine oesophageal motility disorders. The SF-36 Health-Related Quality of Life (HR-QoL) questionnaire was completed and its results compared to a control group without oesophageal symptoms. RESULTS: The study included 33 patients, of which 61% were women, and the mean age was 46.1 (±11.6) years. Causes of NCCP were gastroesophageal reflux disease in 48%, achalasia in 34%, and functional chest pain in 18%. The average progression time for chest pain was 24 (2-240) months, with ≤ 3 events/week in 52% of the patients. The most frequent accompanying symptoms were: regurgitation (81%), dysphagia (72%) and heartburn (66%). Patients with NCCP show deterioration in HR-QoL compared to the control group (P=.01), regardless of chest pain aetiology. The most affected areas were general perception of health, emotional issues, and mental health sub-scale (P>0.05). CONCLUSIONS: In our population, patients with NCCP show deterioration in HR-QoL regardless of the aetiology, frequency, and accompanying symptoms.

Clinical and manometric findings on elderly patients with achalasia.

INTRODUCTION: Data regarding the age impact on the clinical presentation and esophageal motility in adults with idiopathic achalasia are scarce. OBJECTIVE: To asses the clinical and manometric features of elderly patients with idiopathic achalasia. METHODS: The medical charts of 159 patients diagnosed with achalasia were divided into two groups according to the patients' age: ?60 years (n = 123) and >60 years (n = 36). Clinical and manometric findings [esophageal body aperistalsis, basal lower esophageal sphincter (LES) pressure and abnormal LES relaxation] of both groups were compared upon diagnosis. Patients with previous esophageal interventions were excluded. RESULTS: Only chest pain was more common in the ?60 year-old group (51.2% vs. 22.2%, p <0.003). This difference remained when comparing the group of men ≤60 years. Other presenting features (including sex, weight loss, and presence of dysphagia, regurgitation and heartburn) did not differ between the groups. The LES relaxation was incomplete in 70.4% of the cases. No differences on the basal LES pressure, residual LES pressure or the amplitude of the esophageal body contractions between both groups were found. Considering only the classic achalasia cases, symptomatic time before diagnosis was greater in ≤60 years compared with older patients: 24 vs. 12 months (p <0.05), respectively. CONCLUSIONS: These results suggest that chest pain is more common in younger male achalasia patients and residual LES pressure decreases with age.

[Evaluation of non-invasive fibrosis indices in Mexican patients with chronic hepatitis C]. / Evaluación de índices no invasivos de fibrosis en pacientes mexicanos con hepatitis crónica por virus C.

BACKGROUND: Among the many methods proposed to predict the presence of fibrosis in patients with chronic hepatitis C are the indices models obtained from serum biochemical tests, the aspartate aminotransferase-toplatelet ratio index (APRI) and the Forns index (FI). OBJECTIVE: To compare the diagnostic accuracy of the Forns index and APRI for predicting cirrhosis. METHODS: We included 105 patients with chronic hepatitis C and a liver biopsy. The FI and APRI were calculated from the biochemical tests of each patient. Receivers operating characteristic (ROC) curves were calculated to determine the best cutoff to discriminate between cirrhosis (F4), advanced fibrosis (F3-F4), and portal fibrosis (F1) according to the Knodell score. Diagnostic accuracy was assessed by obtaining sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) for each of the indices. RESULTS: ROC curves showed that the best cutoff for predicting cirrhosis (F4) for the FI is >7.64, with Sn 62.5% and Sp 91.8% (Area under the curve, AUC = 0.881), for advanced fibrosis (F3 - F4) the best cutoff value is >6.93 with Sn 42.9% and Sp 89.6% (AUC = 0.772). An APRI value of >1.74 was the best predictor for F4 with Sn 75% and Sp 82% (AUC = 0.799), and a cutoff value of >1.7 for predicting F3-F4 with Sn 47.6% and Sp 85.4% (AUC = 0.768). CONCLUSIONS: The results confirm the utility of both the FI and APRI for predicting advanced fibrosis and cirrhosis.