Prevalence, clinical spectrum and atypical symptoms of gastro-oesophageal reflux in Argentina: a nationwide population-based study

BACKGROUND

Population-based data on gastro-oesophageal reflux in Latin America are lacking.

AIM

To assess gastro-oesophageal reflux symptom prevalence, clinical spectrum and association with the atypical symptoms in our country.

METHODS

Gastro-oesophageal reflux self-report questionnaires validated at Mayo Clinic, USA, were submitted to a sample of 1000 residents (aged 18-80 years) from 17 representative geographical areas of Argentina. The samples were selected and stratified according to age, gender, geographical areas and size of town of residence provided by the Argentine Bureau of Statistics and Census.

RESULTS

The overall prevalence of any typical gastro-oesophageal reflux symptom experienced in the previous year was 61.2% (95% CI, 57.9-64.6), the prevalence of frequent gastro-oesophageal reflux symptoms was 23.0% (95% CI, 20.1-25.9) and the prevalence of gastro-oesophageal reflux disease was 11.9% (95% CI, 9.6-14.1). Frequent gastro-oesophageal reflux symptoms were associated with dysphagia (OR 2.12, 95% CI, 1.27-3.54, P < 0.01), globus (OR 2.22, 95% CI, 1.35-3.66, P < 0.01) and non-cardiac chest pain (OR 1.55, 95% CI, 1.04-2.31, P < 0.05).

CONCLUSIONS

In Argentina, typical symptoms of gastro-oesophageal reflux are highly prevalent at the national level, and frequent gastro-oesophageal reflux symptoms are significantly associated with dysphagia, globus and non-cardiac chest pain.

Long-term outcome of argon plasma ablation therapy for bleeding in 100 consecutive patients with colonic angiodysplasia

PURPOSE

Angiodysplasia is a frequent cause of colonic bleeding. Argon plasma coagulation was reported to be useful in endoscopic hemostasis. However, the long-term outcomes have been poorly evaluated. This study was designed to assess the long-term outcomes of bleeding patients with colonic angiodysplasia treated by argon plasma coagulation.

METHODS

A cohort of 100 patients with gastrointestinal bleeding caused by colonic angiodysplasia was studied prospectively. The endoscopic intervention was considered successful if there was no further overt bleeding and hemoglobin concentration was stabilized (primary end point). Secondary end points were the requirement of blood transfusions, the need for surgery, bleeding-related mortality, and overall mortality.

RESULTS

Overt bleeding resolved and hemoglobin levels were stabilized without transfusions or iron therapy in 85 of 100 patients (85 percent) after a median follow-up of 20 (range, 6-62) months. Transfusion requirements ceased in 90 percent of patients and only one required surgery. No patient died because of hemorrhage. In the subgroup of patients with anemia, mean hemoglobin levels increased from 9.3 (range, 5.5-12.2) g/dl before treatment to 12.6 (range, 7.4-16.7) g/dl after treatment (P < 0.01). The probability of remaining free of rebleeding at one and two year follow-up was 98 percent (95 percent confidence interval, 96-100) and 90 percent (95 percent confidence interval, 83-97), respectively. Among 118 procedures, only two complications were observed (1.7 percent).

CONCLUSIONS

Endoscopic argon plasma ablation therapy is useful in the management of bleeding from colonic angiodysplasia.

Bioactive glass fiber/polymeric composites bond to bone tissue

Bioactive glass fibers were investigated for use as a fixation vehicle between a low modulus, polymeric composite and bone tissue. In an initial pilot study, bioactive glass fiber/polysulfone composites and all-polysulfone control rods were implanted into the rabbit tibia; the study was subsequently expanded with implantation into the rabbit femur. Bone tissue exhibited direct contact with the glass fibers and adjacent polymer matrix and displayed a mechanical bond between the composite and bone tissue after six weeks implantation. Interfacial bond strengths after six weeks implantation averaged 12.4 MPa, significantly higher than those of the all-polymer controls. Failure sites for the composite at six weeks generally occurred in the bone tissue or composite, whereas the failure site for the polymer implants occurred exclusively at the implant/tissue interface. The bioactive glass fiber/polysulfone composite achieved fixation to bone tissue through a triple mechanism: a bond to the bioactive glass fiber, mechanical interlocking between the tissue and glass fibers, and close apposition and possible chemical bond between the portions of the polymer and bone tissue. This last mechanism resulted from an overspill of bioactivity reactions from the fibers onto the surface of the surrounding polymer which we call the "halo" effect.

Argon plasma coagulation for prevention of recurrent bleeding from GI angiodysplasias

BACKGROUND

Angiodysplasia is a frequent cause of GI bleeding. Argon plasma coagulation has been shown to arrest bleeding, but its efficacy for prevention of recurrent bleeding has not been thoroughly evaluated. This study assessed the effectiveness and the safety of argon plasma coagulation for prevention of recurrent bleeding from GI angiodysplasias.

METHODS

A total of 60 patients with GI bleeding caused by angiodysplasia were included. The endoscopic intervention was considered successful if there was no further overt bleeding and if the Hb level stabilized. Recurrent bleeding was defined as any detectable bleeding episode (hematemesis, melena, or hematochezia) or a decrease in Hb level.

RESULTS

Overt bleeding was resolved, and the Hb level stabilized without transfusion or supplemental iron therapy in 50 of the 60 patients (83%) at a median follow-up of 18 months (range 6-38 months). In the subgroup of patients with anemia, mean Hb level increased from 8.6 g/dL (range 5.1-12.2 g/dL) to 12 g/dL (range 8.0-15.2 g/dL) ( p < 0.01). The estimated probability of remaining free of recurrent bleeding at 1- and 2-year follow-up was 86%: 95% CI [73%, 93%] and 80%: 95% CI [64%, 89%], respectively. Among 72 procedures, only two were associated with a complication (2.8%).

CONCLUSIONS

Endoscopic argon plasma coagulation is both effective and safe for prevention of recurrent bleeding from GI angiodysplasia.

Surface reaction layer formation in vitro on a bioactive glass fiber/polymeric composite

In order to provide a fixation vehicle between a polymeric composite femoral hip prosthesis and bone tissue, we fabricated bioactive glass fibers. The glass fibers had a tensile strength of 596 MPa, 14 times that of bulk bioactive glass. After immersion in protein-free simulated body fluid for 10 days, we observed the development of a calcium phosphate layer (specifically, partially crystallized, calcium-deficient carbonated hydroxyapatite) on the surface of the glass fibers. The stages of the surface reaction layer formation were similar to those of 45S5 bioactive glass although the kinetics of the reaction layer formation were slower. We combined the bioactive glass fibers with a polymeric matrix to form a fiber-reinforced composite material and observed the formation of a calcium phosphate layer on the surface of the glass fibers within the composite material after immersion in both protein-free and protein-containing simulated body fluids. The rate of reaction layer formation was reduced in the presence of proteins. In both protein-free and protein-containing solutions, a "halo" of bioactivity reactions was observed on the surface of the polymer in regions surrounding the glass fibers. Our results suggest these glass fibers and glass fiber composites will exhibit bioactivity reactions in vivo.

Large-scale survey of naturally occurring HBV polymerase mutations associated with anti-HBV drug resistance in untreated patients with chronic hepatitis B

Drug resistance is a major limitation for the long-term efficacy of antiviral therapy with nucleos(t)ide analogues (NAs) in chronic hepatitis B (CHB). Antiviral resistance mutations may pre-exist in the overall viral population of untreated patients. We aimed to assess the prevalence of such hepatitis B virus (HBV) variants in a large cohort of NAs-naïve patients with CHB and to explore possible association with viral and host variables. Serum samples from 286 NAs-naïve consecutive patients with CHB were tested for serum HBV-DNA, and 255 of them having HBV-DNA > 1000 IU/mL were further analysed for drug resistance mutations by INNO-LiPA HBV DRv2/v3. NAs-naïve patients analysed were mainly men (73%), Caucasians (85%), hepatitis B e Antigen (HBeAg) negative (79%) and genotype D (69%), with a mean age of 43.2 ± 13.4 years. HBV mutations associated with antiviral drug resistance were detected in 13 (5%) patients: three patients infected with HBV genotype C had the rtM204V + rtL180M mutations associated with lamivudine (LMV) resistance. Four patients had the rtI233V mutation that may reduce sensitivity to adefovir, and three patients had the rtM250L/V mutation typical of entecavir resistance. LMV compensatory mutations rtL80V and rtV173L were seen in two and one patients, respectively. No relationship was seen between presence of resistant or compensatory mutations and HBV-DNA levels, HBeAg/anti-HBe status or previous IFN therapy. These results confirm that HBV mutations, which confer resistance against currently available anti-HBV NAs, may already exist in patients who have never received the drug.

Grasp or brush for biliary sampling at endoscopic retrograde cholangiography? A blinded randomized controlled trial

OBJECTIVES

Brushing, the standard sampling method at endoscopic retrograde cholangiography (ERC), lacks sensitivity for cancer detection. We assessed a novel sampling method using a grasping basket.

METHODS

Fifty-six patients with a suspected malignant biliary stricture were randomized to biliary sampling at ERC using a basket (basket group, N = 30) or a brush (brush group, N = 26), followed by the alternate device. When deemed necessary, strictures were dilated (using 6-mm balloons exclusively). The primary end point was sensitivity for cancer detection at cytopathological examination of the first sample collected in each patient; the cytopathologist was blinded to clinical details and sampling method. All analyses followed an intention-to-treat principle.

RESULTS

All 56 patients had successful sampling with both techniques; 50 (89%) had a final diagnosis of malignant stricture. Sensitivity for cancer detection with the first sample collected in each patient was significantly higher in the basket compared to brush group (20/25 [80%]vs 12/25 [48%], respectively, P= 0.018, OR 4.33, 95% CI 1.24-15.21). Seventeen (34%) of the 50 sample pairs collected from malignant cases showed discordant cytopathological results: 15 patients had a positive basket and a negative brush result while two had the inverse association (P= 0.002, OR 7.5, 95% CI 1.65-47.44). Basketting more frequently yielded positive samples from malignant strictures in case of presampling balloon dilation (27/32 [84%]vs 10/18 [56%], respectively, P= 0.043, OR 4.32, 95% CI 1.14-16.37). Specificity was 100% (both methods).

CONCLUSION

Biliary sampling at ERC using a dedicated basket provided a significantly higher sensitivity for cancer detection than brushing; presampling stricture dilation significantly increased sensitivity.

Evaluation of friction properties of hydrogels based on a biphasic cartilage model

Characterizing hydrogels using a biphasic cartilage model, which can predict their behavior based on structural properties, such as permeability and aggregate modulus, may be useful for comparing active lubrication modes of cartilage and hydrogels for the design of articular cartilage implants. The effects of interstitial fluid pressurization, inherent matrix viscoelasticity and tension-compression nonlinearity on mechanical properties of the biphasic material were evaluated by linear biphasic (KLM), biphasic poroviscoelastic (BPVE) and linear biphasic with anisotropy cartilage models, respectively. The BPVE model yielded the lowest root mean square error and highest coefficient of determination when predicting confined and unconfined compression stress-relaxation response of hydrogels (n=15): 0.220±0.316MPa and 0.93±0.08; and 0.017±0.008MPa and 0.98±0.01 respectively. Since the differences in error between models were not statistically significant, the simplest model we considered, KLM model, was sufficient to predict the mechanical response of this family of hydrogels. The coefficient of friction (COF) of a hydrogel-ceramic articulation was measured at varying loads and pressures to explore the full range of lubrication behavior of hydrogel. Material parameters obtained by biphasic models correlated with COF. Based on the linear biphasic model, COF correlated positively with aggregate modulus (spearman's rho=0.5; p<0.001) and velocity (rho=0.3; p<0.001), and negatively with permeability (rho=-0.3; p<0.001) and load (rho=-0.6; p<0.001). Negative correlation of COF with load and positive correlation with velocity indicated that hydrogel-ceramic articulation was separated by a fluid film. These results together suggested that interstitial fluid pressurization was dominant in the viscoelasticity and lubrication properties of this biphasic material.

Hyperinsulinaemia reduces the 24-h virological response to PEG-interferon therapy in patients with chronic hepatitis C and insulin resistance

Insulin resistance (IR) reduces response to pegylated-interferon (PEG-IFN)/ribavirin in chronic hepatitis C (CHC), but the mechanisms are still undefined. We examined the relationship between baseline insulin levels, the main component affecting homeostasis model of assessment - insulin resistance (HOMA-IR) for assessment of IR in non-diabetic patients, and the 'acute' virological response to PEG-IFN measured 24 h after the first injection and taken as correlate of intracellular interferon signalling. In 62 patients treated with PEG-IFN/Ribavirin, serum insulin and HOMA-IR were assessed at baseline, while hepatitis C virus (HCV)-RNA was measured at baseline and 24 h, 1, 2, 4 and 12 weeks after treatment initiation. Sustained virological response was examined 24 weeks after therapy discontinuation. Mean baseline insulin was 11.52 +/- 8.51 U/L and mean HOMA-IR was 2.65 +/- 2.01 both being significantly higher with advanced liver fibrosis. Hepatitis C virus-RNA decay observed 24 h after the first injection of PEG-IFN was significantly lower (0.7 +/- 0.8 log) in patients with HOMA > or =3 compared with those with HOMA <3 (1.7 +/- 0.8, P = 0.001). A highly significant (r = -0.42) inverse correlation was observed between baseline insulin levels and the 24-h HCV-RNA decay. The difference in early viral kinetics between patients with HOMA > or =3 or <3 resulted in a significant difference in the percentage of patients achieving rapid (week 4) and sustained virological response. Multivariate analysis, inclusive of patient age, HCV genotype and fibrosis stage, identified baseline insulin levels as the main independent variable affecting the 24-h response to PEG-IFN. Hyperinsulinaemia reduces the cellular response to Pegylated-interferon in CHC with IR. Strategies to reduce insulin levels before initiation of treatment should be pursued to improve efficacy of anti-viral treatment.

Uninvestigated dyspepsia in Latin America: a population-based study

We sought to assess the prevalence, severity of symptoms, and risk factors of uninvestigated dyspepsia in a population-based study in Argentina. Eight hundred thirty-nine valid questionnaires were evaluated. Dyspepsia was present in 367 subjects (43.2%; 95% confidence interval [CI], 39.8-46.6); 110 (13.6%) had overlap with gastroesophageal reflux disease (GERD). The group with dyspepsia without GERD consisted of 257 subjects (29.6%; 95% CI, 26.5-32.7), 183 (71.1%) had ulcer-like dyspepsia, and 74 (28.9%) had dysmotility-like dyspepsia. Symptoms were considered very severe in 1.9%, severe in 14.0%, moderate in 59.5%, and mild in 24.5% of the subjects. Dyspepsia was associated with a score >14 on the psychosomatic symptom scale (PSC) (OR, 2.52; 95% CI, 1.75-3.61), a family history of diseases of the esophagus or stomach (OR, 1.73; 95% CI, 1.19-2.52) and an educational level >12 years (OR, 1.55; 95% CI, 1.05-2.29). Dyspepsia is especially prevalent in Argentina. In a significant proportion of dyspeptic subjects, the severity of symptoms interferes with daily activities. A higher PSC, positive family history, and a higher educational level are risk factors for dyspepsia.

Usefulness of a mobile app to improve performance of specialists in responding correctly to CRC screening and surveillance clinical scenarios

Background and study aims  The adherence to and knowledge of physicians about colorectal cancer (CRC) screening and surveillance guidelines is still suboptimal, threatening the effectiveness of CRC screening. This study assessed the usefulness of a mobile decision support system (MDSS) to improve physician ability to recommend proper timing of and intervals for CRC screening and surveillance. Patients and methods  This was a binational, single-blinded, randomized clinical trial including gastroenterologists and colorectal surgeons from Argentina and Uruguay. The specialists were invited to respond to a questionnaire with 10 CRC screening and surveillance clinical scenarios, randomized into two groups, with and without access to a dedicated app (CaPtyVa). The main outcome measure was the proportion of physicians correctly solving at least 60 % of the clinical cases according to local guidelines. Results  A total of 213 physicians were included. The proportion of physicians responding correctly at least 60 % of the vignettes was higher in the app group as compared to the control group (90 % versus 56 %) (relative risk [RR] 1.6 95 % confidence interval [CI] 1.34-1.91). The performance was also higher in the app group for both vignette categories: CRC screening (93 % vs 75 % RR 1.24, 95 %CI 1.01-1.40) and surveillance (85 % vs 47 % RR 1.81 95 %CI 1.46-2.22), respectively. Physicians considered the app easy to use and of great utility in daily practice. Conclusions  A MDSS was shown to be a useful tool that improved specialist performance in solving CRC screening and surveillance clinical scenarios. Its implementation in daily practice may facilitate the adherence of physicians to CRC screening and surveillance guidelines.

Rapid diagnosis of mucinous cystic pancreatic lesions by on-site cyst fluid glucometry

INTRODUCTION

Available intracystic biomarkers show a limited accuracy for characterizing cystic pancreatic lesions (CPL). Glucose is an attractive alternative due to its availability, low cost and the possibility of on-site quantification by glucometry.

AIM

To evaluate the diagnostic accuracy of on-site glucometry from samples obtained by EUS-FNA in the differential diagnosis between mucinous from non-mucinous CPL.

METHODS

Retrospective, multicentre, cross-sectional study of patients who underwent EUS-FNA of a CPL. A derivation and a validation cohorts were evaluated. Intracystic glucose was quantified by on-site glucometry and colorimetry in the lab. Final diagnosis was based on surgical specimens or global evaluation of clinical and imaging data, cytology and intracystic CEA. Diagnostic accuracy was based on Receiver Operating Curve (ROC) curve analysis. Intraclass correlation coefficient (ICC) between on-site and lab glucose levels was calculated.

RESULTS

Seventy two patients were finally analysed (40 in the derivation cohort and 32 in the validation cohort). Intracystic glucose levels by on-site glucometry was 12.3 ± 28.2 mg/dl for mucinous CPL and 103.3 ± 58.2 mg/dl for non-mucinous CPL, p < 0.001. For an optimal cut-off point of 73 mg/dl, on-site glucose had a sensitivity, specificity, and positive and negative predictive value for the diagnosis of mucinous CPL of 0.89, 0.90, 0.94, 0.82 respectively in the derivation cohort, and 1.0, 0.71, 0.91, 1.0 respectively in the validation cohort. Correlation of on-site and lab glucose quantification was very high (ICC = 0.98).

CONCLUSION

On-site glucometry is a feasible, accurate and reproducible method for the characterization of CPL after EUS-FNA. It shows an excellent correlation with laboratory glucose values. Registration number: 2019/612.

Use of stool molecular panel in hospitalized patients with diarrhea. Experience in a tertiary care center

Infectious diarrhea is a common health issue that affects a large number of individuals each year. It causes significant morbidity and mortality, greatly impacting healthcare system costs. Rapid detection of the causative organism and timely treatment alters the management and outcome of the condition. Molecular panels in stool allow to analyze a wide range of pathogens quickly and easily. For this study, a cross-sectional cohort analysis with a retrospective analysis of adult patients hospitalized with diarrhea and negative conventional stool bacteriological studies was conducted. Data obtained from the use of molecular panels in stool and the role of endoscopy in the diagnostic pathway were analyzed. A positivity rate of 52% (n=41) out of a total of 79 samples was reported. The test contributed to a change in therapeutic approach in 58% (n=46) of the patients. Among the patients with a negative molecular panel, 39.5% underwent further evaluation with colonoscopy involving biopsies, resulting in a diagnostic yield of 87%. Based on these results, we can conclude that molecular techniques contribute to the diagnosis and change in therapeutic approach in hospitalized patients with diarrhea.

Comparison of defibrillation thresholds using monodirectional electrical vector versus bidirectional electrical vector

BACKGROUND

Currently, two main lead configurations are used for implantable cardioverter-defibrillators (ICD). One generates a monodirectional electrical vector by using the can surface as an active part (hot can) together with a right ventricular defibrillation coil. The other one (TRIAD) produces a bidirectional electrical vector by adding a proximal defibrillation electrode on the same lead. The purpose of this prospective study was to determine whether there is a difference between these configurations in terms of the acute defibrillation threshold (DFT). The secondary objective was to evaluate the possible sequential effect of successive arrhythmia induction and defibrillation shocks on the final DFT value.

METHODS

In 44 patients (37 males, 7 females, mean age 59.18 +/- 12.05 years; mean ejection fraction 35.21 +/- 11.69%), a Hot Can Ventak family ICD (Guidant, St. Paul, MN, USA) was implanted in a left pectoral pocket. During the implant procedure, step-down to failure DFT testing was performed twice in each patient using the two different above-mentioned configurations: the bidirectional and the monodirectional. The first configuration to be tested was determined by a 1:1 randomization by center.

RESULTS

The step-down DFT protocol was followed in 35 patients. The average DFT was 8.6 +/- 4.0 J for TRIAD and 10.4 +/- 4.3 J for the monodirectional (p = 0.009) lead configuration; this represents a 16.3% decrease in the DFT using a bidirectional configuration. Furthermore, no relationship between the final DFT and the number of ventricular fibrillation inductions and shocks received was observed, confirming the secondary objective.

CONCLUSIONS

Compared to the monodirectional electrical vector, the bidirectional electrical vector is clearly more beneficial for the patient.

[Effects of simvastatin on plasma levels of lipids, lipoproteins and apolipoproteins in primary hypercholesterolemia]

To evaluate the effectiveness, tolerance and safety of simvastatin (MK 733), a new HMG-CoA reductase inhibitor, a 28-week, single blind study with placebo was carried out on 10 patients suffering from primary hypercholesterolaemia. All patients followed the AHA Phase 1 or Phase 2 diet and underwent active treatment for 24 weeks with increasing doses of simvastatin from 10 to 40 mg in a single evening administration. A reduction in plasma levels of total cholesterol (-29%, p less than 0.001 and -41%, p less than 0.001), LDL cholesterol (-35%, p less than 0.001 and -49%, p less than 0.001), VLDL cholesterol (-9%, ns and -38%, ns), Apo-B (-27%, p less than 0.005 and -37%, p less than 0.001), Apo-A2 (-3%, ns and -3%, ns), and triglycerides (+2%, ns and -10%, ns), was obtained in the VIth and XXIVth week. There was also an increase in HDL cholesterol (+4%, ns and +17%, p less than 0.05), HDL2 subfractions (+9%, p less than 0.05 and +36%, p less than 0.05), HDL3 (+3%, ns and +11%, ns) and Apo-A1 (+7%, ns and +4%, ns). In all patients, simvastatin was generally tolerated and there were no clinical, laboratory or ophthalmological side-effects related to the drug. If long-term studies confirm its safety, simvastatin will offer excellent prospects for the prevention of ischaemic cardiopathy.

[Bicameral stimulation in a case of corrected transposition of the great vessels]

A patient with Corrected Transposition of the Great Arteries (CTGA), mild incompetence of left A-V valve, complete atrioventricular block without associated anatomic lesions, in whom a bicameral permanent pace maker has been implanted, is described. The procedure of implantation did not present any particular problem; the stability of the electrocatheters was good. The exercise tolerance with DDD mode stimulation was normal and definitively better as compared to that achieved with ventricular stimulation at progressively higher stimulation frequency. The patient is now well and attending a normal physical activity.

Clinical utility of the solid meal test during high-resolution esophageal manometry. A study in a Latin American population

INTRODUCTION AND AIMS

The solid test meal (STM) is a challenge test that is done during esophageal manometry and appears to increase the diagnostic yield of the study. The aim of our analysis was to establish the normal values for STM and evaluate its clinical utility in a group of Latin American patients with esophageal disorders versus healthy controls.

MATERIAL AND METHODS

A cross-sectional study was conducted on a group of healthy controls and consecutive patients that underwent high-resolution esophageal manometry, in which STM was done at the final part of the study and consisted of asking the subjects to eat 200 g of precooked rice. The results were compared during the conventional protocol and the STM.

RESULTS

Twenty-five controls and 93 patients were evaluated. The majority of the controls (92%) completed the test in under 8 min. The STM changed the manometric diagnosis in 38% of the cases. The STM diagnosed 21% more major motor disorders than the conventional protocol; it doubled the cases of esophageal spasm and quadrupled the cases of jackhammer esophagus, whereas it demonstrated normal esophageal peristalsis in 43% of the cases with a previous diagnosis of ineffective esophageal motility.

CONCLUSIONS

Our study confirms the fact that complementary STM during esophageal manometry adds information and enables a more physiologic assessment of esophageal motor function to be made, compared with liquid swallows, in patients with esophageal motor disorders.