Helicobacter pylori Secondary Antibiotic Resistance after One or More Eradication Failure: A Genotypic Stool Analysis Study.

Helicobacter pylori (H. pylori) antibiotic resistance is the leading cause for unsuccessful eradication therapy. After one or more failures, the chance of encountering secondary antibiotic resistance increases. The aim of this study was to characterize genotypic secondary resistance in a cohort of southern Italian H. pylori patients with at least one previous failure. Such patients collected stool samples using a dedicated kit (THD fecal testTM), and bacterial DNA was extracted and amplified using RT-PCR. Resistance to clarithromycin, amoxicillin, metronidazole, levofloxacin, and tetracycline was assessed using a high-resolution melting curve. We enrolled 50 patients. A total of 72% of patients failed one previous antibiotic course, 16% failed two, 10% failed three, and 2% failed four. The rate of secondary antibiotic resistance was 16% for clarithromycin, 18% for metronidazole, 14% for amoxicillin, 14% for levofloxacin, and 2% for tetracycline. Among the eight clarithromycin-resistant patients, five (62.5%) previously received a clarithromycin-based regimen. The same rate was 33.3% (3/9) for metronidazole. The only tetracycline-resistant patient had received Pylera. In conclusion, our data seem to show that, even though secondary resistance is not very high, resistance to clarithromycin could be very likely related to previous exposure to this antibiotic.

Comparison of Transient Elastography and Point Shear Wave Elastography for Analysis of Liver Stiffness: A Prospective Study.

Liver stiffness measurement (LSM) by Fibroscan is the most used non-invasive method to assess liver fibrosis. Recently, point-shear wave elastography (pSWE) has been introduced as a simple alternative non-invasive test. Therefore, we aimed to compare the results of these two techniques. One hundred and eighty-four consecutive patients attending our outpatient ultrasound clinic were recruited. LSM was performed by both Fibroscan and pSWE. Statistical analysis was conducted by Spearman's test for correlation and linear regression. Bland-Altman graphs and ROC curves were drawn with area under the curve (AUC). Overall, the correlation of LS between Fibroscan and pSWE was substantial (r = 0.68, p < 0.001). Linear regression showed a coefficient b= 0.94 ± 0.02. The Bland-Altman plot found a bias of -0.10, with only 11 values exceeding the 95% confidence interval. When only considering patients with a LSM of > 10 kPa (n = 31), we found an excellent r = 0.79 (0.60-0.90, p < 0.001). A cutoff of 12.15 kPa for pSWE had sensitivity = 74.2% and specificity = 99.3% to detect relevant fibrosis, with an AUC = 0.98. The highest correlation was observed for hepatitis C (r = 0.91) and alcoholic liver disease (ALD)(r = 0.99). In conclusion, pSWE shows LSM estimation in agreement with Fibroscan in most cases, and the best concordance was observed for hepatitis C and ALD, and for higher ranges of LS.

Molecular Pathways of Carcinogenesis in Familial Adenomatous Polyposis.

Familial adenomatous polyposis (FAP) is a genetic syndrome characterized by the presence of multiple polyps in the gastrointestinal tract and a wide range of systemic extra-intestinal manifestations. Patients affected will inevitably undergo abdominal surgery due to the malignant transformation of one or more adenomas. The pathogenesis of the disease is based on a loss of function mutation in adenomatous polyposis coli (APC), a tumor-suppressor gene, inherited following a Mendelian pattern. This gene is a key component of multiple cell functions that cooperate for homeostasis; when mutated, it contributes to the progression of colorectal adenoma into cancer. Recent studies have demonstrated that several additional mechanisms may influence this process, such as alterations in gut microbiota composition and mucosal barrier immunity, interaction with the immune microenvironment and inflammation, the hormone estrogen, and other signaling pathways. These factors represent promising targets of future therapies and chemoprevention, aiming to alter the progressive nature of the disease and improve the quality of life of families affected. Therefore, we performed a narrative review about the current knowledge of the aforementioned pathways involved in colorectal cancer pathogenesis in FAP, exploring the genetic and environmental factors that may contribute to the development of CRC in FAP.

Diet and Lifestyle Habits in Early-Onset Colorectal Cancer: A Pilot Case-Control Study.

BACKGROUND: Early-onset colorectal cancer (eoCRC), defined as a colorectal cancer (CRC) in patients younger than 50 years old, shows an increasing incidence worldwide in the latest years. The role of exogenous factors associated with CRC has been largely overlooked in eoCRC. Here, we conducted a case-control study to evaluate the diet and the lifestyle habits in an Italian population of patients with eoCRC, compared to age-matched healthy controls (HCs). METHODS: We enrolled 118 subjects (47 cases, 71 controls) in a third-level academic hospital. We analyzed epidemiological features (age, sex, body mass index), lifestyle behaviors (smoking habits, physical activity, type of diet, use of dietary supplements), and eating habits (semiquantitative food-frequency questionnaire) in eoCRCs and HCs, covering the previous 5 years. RESULTS: In our cohort, positive family history of CRC was significantly associated with the development of eoCRC (p = 0.004). Fresh meat (p = 0.003), processed meat (p < 0.001), dairy products (p = 0.013), and smoking (p = 0.0001) were significantly associated with eoCRC compared to controls. Other variables did not differ significantly between the two groups. CONCLUSION: Fresh and processed meat, dairy products, and smoking could be considered significant risk factors for eoCRC, although further confirmation by international multicenter studies is desirable. Diet and smoking could be the main areas of future interventions for eoCRC primary prevention.

Estrogen Receptors in Colorectal Cancer: Facts, Novelties and Perspectives.

Colorectal cancer (CRC) is the second cause of cancer-related death in both sexes worldwide. As pre-menopausal women are less likely to develop CRC compared to age-matched men, a protective role for estrogens has been hypothesized. Indeed, two isoforms of nuclear estrogen receptors (ER) have been described: ERα and ERß. While the binding of 17beta-estradiol to ERα activates anti-apoptotic pathways, the interaction with ERß activates caspase-3, inducing apoptosis. In this regard, several pieces of evidence show that ERß tends to be under-regulated in advanced adenomas and CRC, with an opposite trend for ERα. Furthermore, ERß stimulation slows adenomatous polyp growth and modulates relevant CRC pathways. Based on such considerations, dietary modulation of ER is promising, particularly in subjects with genetic predisposition for CRC. Nevertheless, the main limitation is the lack of clinical trials on a large population scale.

Risk factors and clinical characteristics of early-onset colorectal cancer vs. late-onset colorectal cancer: a case-case study.

BACKGROUND AND OBJECTIVES: Early-onset colorectal cancer (eoCRC), defined as colorectal cancer (CRC) before the age of 50 is increasing in incidence. We evaluated exogenous and endogenous risk factors, and clinical features of eoCRC, compared to late-onset CRC (loCRC). METHODS: In this retrospective case-case study, patients were prospectively enrolled from 2015 to 2018. We collected clinical features (age, sex, time from symptom onset to diagnosis, symptoms, family history, smoking and alcohol habits, diabetes, BMI, and genetic analysis) and tumor characteristics. Independent risk factors for eoCRC and odds ratios (ORs) were identified. RESULTS: Fifty-four eoCRCs and 494 loCRCs were enrolled. Patients with eoCRC experienced longer delay time from symptom onset to diagnosis: 40.7% were diagnosed within 6 months from symptoms onset, compared to 85.6% of patients with loCRC (P < 0.0001). They differed for sex, presence of symptoms, family history, smoking habit, alcohol intake, and BMI. Rectal localization was more closely associated with eoCRC (64.8%) than loCRC (34.5%, P < 0.0001). Family history of CRC was associated with eoCRC (OR = 8.8). When family history occurred with hereditary cancer syndromes, the OR for eoCRC increased to 21. CONCLUSION: In young adults with alarming symptoms, CRC must be suspected to avoid delay time from symptom onset to diagnosis and genetic risk assessment has to be evaluated. Smoking habits, alcohol intake, and BMI are not associated with eoCRC.

Oral and Fecal Microbiota in Lynch Syndrome.

BACKGROUND: The role of microbiota in Lynch syndrome (LS) is still under debate. We compared oral and fecal microbiota of LS saliva and stool samples with normal healthy controls (NHC). METHODS: Total DNA was purified from feces and saliva to amplify the V3-V4 region of the 16s rRNA gene. Sequences with a high-quality score and length >250 bp were used for taxonomic analysis with QIIME software. RESULTS: Compared to NHC, LS fecal samples demonstrated a statistically significant increase of Bacteroidetes and Proteobacteria and a significant decrease of Firmicutes at the phylum level and of Ruminococcaceae at the family level. Moreover, LS oral samples exhibited a statistically significant increase of Veillonellaceae and Leptotrichiaceae and a statistically significant decrease of Pasteurellaceae. A beta-diversity index allowed differentiation of the two groups. CONCLUSIONS: A peculiar microbial signature is associated with LS, similar to that of sporadic colorectal cancer and Crohn's disease. These data suggest a possible role of proinflammatory bacteria in tumor development in a condition of genetic predisposition, such as LS.