Periprocedural safety profile of peroral endoscopic myotomy (POEM)-a retrospective analysis of adverse events according to two different classifications.

BACKGROUND: Peroral endoscopic myotomy (POEM) is nowadays a standard method for treatment of achalasia; nevertheless, it remains an invasive intervention with corresponding risk of adverse events (AEs). The classification and grading of AEs are still a matter of discussion. The aim of our retrospective study was to assess the occurrence of all "undesirable" events and "true" adverse events in patients undergoing POEM and to compare the outcomes when either Clavien-Dindo classification (CDC) or American Society of Gastrointestinal Endoscopy (ASGE) lexicon classification applied. METHODS: This was a retrospective analysis of prospectively managed database of all patients who had undergone POEM between December 2012 and August 2018. We assessed the pre-, peri-, and early-postoperative (up to patient's discharge) undesirable events (including those not fulfilling criteria for AEs) and "true" AEs according the definition in either of the classifications. RESULTS: A total of 231 patients have successfully undergone 244 POEM procedures (13 × re-POEM). Twenty-nine procedures (11.9%) passed uneventfully, while in 215 procedures (88.1%), a total of 440 undesirable events occurred. The CDC identified 27 AEs (17 minor, 10 major) occurring in 23/244 (9.4%) procedures. The ASGE lexicon identified identical 27 AEs (21 mild or moderate, 6 severe or fatal) resulting in the severity distribution of AEs being the only difference between the two classifications. Only the absence of previous treatment was found to be a risk factor [p = 0.047, OR with 95% CI: 4.55 (1.02; 20.25)] in the combined logistic regression model. CONCLUSION: Undesirable events are common in patients undergoing POEM but the incidence of true AEs is low according to both classifications. Severe adverse events are infrequent irrespective of the classification applied. CDC may be more appropriate than ASGE lexicon for classifying POEM-related AEs given a surgical nature of this procedure.

Endoscopic pyloromyotomy for the treatment of severe and refractory gastroparesis: a pilot, randomised, sham-controlled trial.

OBJECTIVE: Endoscopic pyloromyotomy (G-POEM) is a minimally invasive treatment option with promising uncontrolled outcome results in patients with gastroparesis. DESIGN: In this prospective randomised trial, we compared G-POEM with a sham procedure in patients with severe gastroparesis. The primary outcome was the proportion of patients with treatment success (defined as a decrease in the Gastroparesis Cardinal Symptom Index (GCSI) by at least 50%) at 6 months. Patients randomised to the sham group with persistent symptoms were offered cross-over G-POEM. RESULTS: The enrolment was stopped after the interim analysis by the Data and Safety Monitoring Board prior to reaching the planned sample of 86 patients. A total of 41 patients (17 diabetic, 13 postsurgical, 11 idiopathic; 46% male) were randomised (21 G-POEM, 20-sham). Treatment success rate was 71% (95% CI 50 to 86) after G-POEM versus 22% (8-47) after sham (p=0.005). Treatment success in patients with diabetic, postsurgical and idiopathic gastroparesis was 89% (95% CI 56 to 98), 50% (18-82) and 67% (30-90) after G-POEM; the corresponding rates in the sham group were 17% (3-57), 29% (7-67) and 20% (3-67).Median gastric retention at 4 hours decreased from 22% (95% CI 17 to 31) to 12% (5-22) after G-POEM and did not change after sham: 26% (18-39) versus 24% (11-35). Twelve patients crossed over to G-POEM with 9 of them (75%) achieving treatment success. CONCLUSION: In severe gastroparesis, G-POEM is superior to a sham procedure for improving both symptoms and gastric emptying 6 months after the procedure. These results are not entirely conclusive in patients with idiopathic and postsurgical aetiologies. TRIAL REGISTRATION NUMBER: NCT03356067; ClinicalTrials.gov.

Near-focus narrow-band imaging classification of villous atrophy in suspected celiac disease: development and international validation.

BACKGROUND AND AIMS: There are no agreed-on endoscopic signs for the diagnosis of villous atrophy (VA) in celiac disease (CD), necessitating biopsy sampling for diagnosis. Here we evaluated the role of near-focus narrow-band imaging (NF-NBI) for the assessment of villous architecture in suspected CD with the development and further validation of a novel NF-NBI classification. METHODS: Patients with a clinical indication for duodenal biopsy sampling were prospectively recruited. Six paired NF white-light endoscopy (NF-WLE) and NF-NBI images with matched duodenal biopsy sampling including the bulb were obtained from each patient. Histopathology grading used the Marsh-Oberhuber classification. A modified Delphi process was performed on 498 images and video recordings by 3 endoscopists to define NF-NBI classifiers, resulting in a 3-descriptor classification: villous shape, vascularity, and crypt phenotype. Thirteen blinded endoscopists (5 expert, 8 nonexpert) then undertook a short training module on the proposed classification and evaluated paired NF-WLE-NF-NBI images. RESULTS: One hundred consecutive patients were enrolled (97 completed the study; 66 women; mean age, 51.2 ± 17.3 years). Thirteen endoscopists evaluated 50 paired NF-WLE and NF-NBI images each (24 biopsy-proven VAs). Interobserver agreement among all validators for the diagnosis of villous morphology using the NF-NBI classification was substantial (κ = .71) and moderate (κ = .46) with NF-WLE. Substantial agreement was observed between all 3 NF-NBI classification descriptors and histology (weighted κ = 0.72-.75) compared with NF-WLE to histology (κ = .34). A higher degree of confidence using NF-NBI was observed when assessing the duodenal bulb. CONCLUSIONS: We developed and validated a novel NF-NBI classification to reliably diagnose VA in suspected CD. There was utility for expert and nonexpert endoscopists alike, using readily available equipment and requiring minimal training. (Clinical trial registration number: NCT04349904.).

Celiac disease in adults.

Celiac disease is a lifelong autoimmune disorder that occurs in genetically predisposed people when consuming gluten. Its prevalence is around 1% of the population with about twice higher proportion of women. Celiac disease is one of the most common causes of malabsorption, however, its manifestations can be quite diverse - from completely asymptomatic to fully developed malabsorption syndrome. Extraintestinal manifestations are a common finding in adults. The gold standard of diagnosis is the serological detection of specific antibodies (the serum tissue transglutaminase IgA antibodies) in combination with a typical histological finding from a duodenal biopsy. Causal treatment is a lifelong gluten-free diet. Strict adherence to gluten-free diet will reduce the risk of serious complications (intestinal T-cell lymphoma). In the following case report we present a case of a 58-year-old patient, who have been diagnosed with celiac disease at this age based on non-classical symptoms. Specifically, these were multiple pathological fractures from metabolic bone disease due to malabsorption of calcium and vitamin D and subsequent secondary hyperparathyroidism.

Gentamicin submucosal lavage during peroral endoscopic myotomy (POEM): a retrospective analysis.

BACKGROUND AND AIMS: Peroral endoscopic myotomy (POEM) is an evolving therapeutic modality for achalasia. According to the original Inoue's technique, a submucosal lavage with gentamicin has been practiced due to the fear of infection. This single-tertiary center study was intended to assess the clinical significance of the topical antibiotic lavage during POEM. METHODS: A retrospective analysis of prospectively collected data was conducted. The outcomes of patients who received the gentamicin lavage (group A) during POEM were compared to those who did not (group B). The main outcome variables were infectious adverse events, post-POEM fever, and markers of systemic inflammatory response. One day before and after POEM, all patients received systemic antibiotic prophylaxis with ceftriaxone. RESULTS: Of 124 consecutive patients having undergone POEM, 60 patients received a lavage with 80 mg of gentamicin into the submucosal tunnel before starting the myotomy, while 64 patients did not. The overall treatment success at 3 months did not differ between the two groups (group A 94.7 vs. 97.5% group B). We did not experience any significant infectious adverse events in either group. CRP and WBC levels were lower in patients with lavage versus those without [CRP: median 52.7 (IQR 34.9) vs. 69.5 (54.1); p = 0.01; WBCs: median 10.9 (IQR 3.3) vs. 12.6 (3.9); p < 0.01]. Post-procedural fever was present in 10% of patients in either group. CONCLUSIONS: During POEM, the submucosal lavage with gentamicin prior to the myotomy does not play a role in the prevention of clinically significant infectious adverse events, although the systemic inflammatory response may be decreased.

Erratum to: Per-oral endoscopic myotomy (POEM): mid-term efficacy and safety.

The Given Names and Family Names were all inadvertently inverted. The correct order is: Jan Martinek, Hana Svecova, Zuzana Vackova, Radek Dolezel, Ondrej Ngo, Jana Krajciova, Eva Kieslichova, Radim Janousek, Alexander Pazdro, Tomas Harustiak, Lucie Zdrhova, Pavla Loudova, Petr Stirand, Julius Spicak. The original article was corrected.

Per-oral endoscopic myotomy (POEM): mid-term efficacy and safety.

BACKGROUND AND AIMS: Per-oral endoscopic myotomy (POEM) is becoming a standard treatment for achalasia. Long-term efficacy and the rate of post-POEM reflux should be further investigated. The main aim of this study was to analyze safety and mid-term (12 and 24 months) clinical outcomes of POEM. METHODS: Data on single tertiary center procedures were collected prospectively. The primary outcome was treatment success defined as an Eckardt score < 3 at 12 and 24 months. A total of 155 consecutive patients with achalasia underwent POEM; 133 patients were included into the analysis (22 patients will be analyzed separately as part of a multicenter randomized clinical trial). RESULTS: POEM was successfully completed in 132 (99.2%) patients, and the mean length of the procedure was 69.8 min (range 31-136). One patient underwent a drainage for pleural effusion; no other serious adverse events occurred. Treatment success at 3, 12, and 24 months was observed in 95.5% (CI 89.6-98.1), 93.4% (86.5-96.8), and 84.0% (71.4-91.4) of patients, respectively. A total of 11 patients (8.3%) reported initial treatment failure (n = 5) or later recurrence (n = 6). The majority of relapses occurred in patients with achalasia type I (16.7 vs. 1.1% achalasia type II vs. 0% achalasia type III; p<0.05). At 12 months, post-POEM reflux symptoms were present in 29.7% of patients. At 3 months, mild reflux esophagitis was diagnosed in 37.6% of patients, and pathological gastroesophageal reflux was detected in 41.5% of patients. A total of 37.8% of patients had been treated with a proton pump inhibitor. CONCLUSION: POEM resulted in greater than 90% treatment success at 12 months which tends to decrease to 84% after 2 years. More than one-third of the patients had mild reflux symptoms and/or mild esophagitis.

Allgrove syndrome with prominent neurological symptoms. Case Report.

We report a young woman with the clinical picture of Allgrove syndrome in whom neurological symptoms are prominent. It usually presents in the first decade of life with a deficiency of tears, recurrent vomiting and dysphagia due to achalasia, severe hypoglycemic seizures and shock due to adrenal insufficiency. Neurological symptoms such as hyperreflexia, dysarthria, hypernasal speech, ataxia, sensory impairment, muscle weakness, and mental retardation are extremely slow to develop and manifest at a later age. Diagnosis was based on clinical presentation and laboratory findings. She is the first patient from the Czech Republic with genetic confirmation of Allgrove syndrome. This patient is one of about 100 cases described in the literature and one of the few patients with all the main typical clinical features.

[A novel typing method and scheme for Streptococcus pneumoniae]. / Nová metoda a schéma typizace Streptococcus pneumoniae.

STUDY AIM: To introduce a novel molecular PCR method for the typing of Streptococcus pneumonia in the National Reference Laboratory (NRL) for Streptococcal Infections. MATERIAL AND METHODS: Strains of Streptococcus pneumoniae are referred to the NRL from different regions of the Czech Republic. Generally, the identification and typing are based on strain morphology, optochin susceptibility, bile solubility, latex agglutination, and the Quellung reaction. Since 2012, a novel multiplex polymerase chain reaction (mPCR) assay has been introduced. The novel assay was tested on 210 S. pneumoniae isolates and 8 isolates of the related species S. pseudopneumoniae, S. sanguinis, and S. oralis. RESULTS: The NRL for Streptococcal Infections has included a novel mPCR assay in the algorithm of S. pneumoniae identification and typing. The mPCR assay was able to identify and type any pneumococcal strain from the study collection, with the isolates of the related species remaining negative. The mPCR assay showed 100% sensitivity and specificity in this study. The pCR appeared to be an excellent tool for S. pneumoniae typing. CONCLUSION: Until recently, S. pneumoniae serotypes and serogroups were differentiated using a serological approach (Quellung reaction), but the NRL for Streptococcal Infections has switched to a novel mPCR assay. This molecular tool improves S. pneumoniae typing, making it more accurate.

[Invasive meningococcal disease in the Czech Republic - analysis of the epidemiological situation and vaccination strategy recommendations]. / Invazivní meningokokové onemocnení v Ceské republice - analýza epidemiologické situace a doporucení k vakcinacní strategii.

AIMS: Analysis of invasive meningococcal disease (IMD) surveillance data including molecular epidemio-logy data. Vaccination strategy recommendations based on the current epidemiological situation of IMD in the Czech Republic and availability of meningococcal vaccines. MATERIAL AND METHODS: IMD surveillance data are compiled by the National Reference Laboratory for Meningococcal Disease (NRL) from routinely reported data and NRL data after clearing out duplicate data. Neisseria meningitidis (N.m.) isolates referred to the NRL are confirmed and characterized in detail according to internationally validated methods. RESULTS: The current epidemiological situation of IMD is relatively favourable - the incidence rates have been below 1/100,000 population for several years, but show a slightly upward trend over more than 40-year period (1970-2012). A return to the typical prevalence of serogroup B accounting for up to 75% of cases has recently been shown. In this context, the upward trend in IMD caused by serogroup Y associated with a high case fatality rate in the Czech Republic cannot be overseen or even underestimated. The hypervirulent clonal complex cc11 characteristic of N.m.C:2a:P1.2,5 prevailed in this country between 1993 and 2004, but decreased in the following years and currently, hypervirulent clonal complexes characteristic of N.m.B (cc18, cc32, cc41/44, and cc269) are the most common in the Czech Republic. The average overall case fatality rate in the Czech Republic is 10%, but varies between causative serogroups: the highest case fatality rate has been caused by serogroup Y (16.7% ), followed by serogroup C (12.3%), and serogroup W135 (11.7%), while serogroup B only accounts for a case fatality rate of 7.8%. In the age group under one year, the incidence of IMD caused by serogroup B remains three to five times as high as in the age groups 1-4 years and 15-19 years throughout the surveillance period. The highest numbers of IMD cases caused by serogroup B have been reported in 3-7-month-olds. CONCLUSION: Based on the IMD surveillance data from the Czech Republic, the NRL recommends a vaccination strategy to provide an adequate protection to individuals. To induce an immune response as wide as possible, the tetravalent meningococcal conjugate vaccine A,C,Y,W135 in combination with the newly registered MenB vaccine designed by reverse vaccinology should be given. To maintain immunity, subsequent booster doses are required at intervals depending on the primary vaccination age.

Interventional functional diagnostics in gastrointestinal endoscopy: Combining diagnostic and therapeutic tools in the endoscopy suite with the functional lumen imaging probe.

With technical progress of gastrointestinal functional testing, there has been a demand for more comprehensive examination of esophageal physiology and pathophysiology beyond high-resolution manometry. A new interventional technology based on impedance planimetry, the functional lumen imaging probe (FLIP), enables intraluminal measurement of distensibility and compliance of hollow organs. EndoFLIP uses balloon catheters to measure diameter and distension pressure to calculate cross-sectional area and distensibility in different organs (mostly esophagus, stomach, anorectal region) and can be used in wide variety of indications (diagnostics, pre- and post-treatment evaluation) and currently serves as a helpful adjunctive tool in ambiguous clinical cases. EsoFLIP is a therapeutic variation that uses a stiffer balloon catheter allowing for dilation. The trend to simplify the clinical process from diagnosis to treatment tends to a one-session procedure combining diagnostics and therapeutic interventions. In specified conditions like e.g. achalasia or gastroparesis, a combination of EndoFLIP and EsoFLIP procedures may therefore be useful. The aim of this narrative review is to introduce the clinical use of FLIP and its potential benefit in combined diagnostic-therapeutic procedures.

Prevalence of neurodegenerative/demyelinating disorders in patients with achalasia.

Introduction: Esophageal achalasia is a primary motility disorder. Although the exact pathogenesis is unknown, autoimmune, and neurodegenerative processes seem to be involved similarly to neurodegenerative and/or demyelinating disorders (NDDs). We hypothesized that the prevalence of NDD may be higher among patients with achalasia and vice versa as the background pathogenetic mechanisms are similar. Methods: This was a prospective, comparative questionnaire-based study. Patients with achalasia and patients with NDD were enrolled. Selected patients with achalasia were thoroughly examined by a neurologist and selected patients with NDD were examined by a gastroenterologist to confirm or rule out NDD or achalasia. We assessed the prevalence of both achalasia and NDD and compared them with their prevalence in general population. Results: A total of 150 patients with achalasia and 112 patients with NDD were enrolled. We observed an increased prevalence of NDD among patients with achalasia (6.0% (9/150); 95% CI (confidence interval): 3.1-11.2%) as compared to the estimated 2.0% prevalence in general population (p = 0.003). Although 32 out of 112 patients (28.6%) with NDD reported dysphagia, we did not observe significantly increased prevalence of achalasia in these patients (1.8% (2/112) vs 0.8% in general population, p = 0.226). Conclusion: The prevalence of NDD was significantly higher among patients with achalasia (6.0%) compared to general population (2.0%), suggesting an association of these disorders. Large-volume studies are necessary to confirm this finding.

Esophageal Motility Patterns After Peroral Endoscopic Myotomy in Patients With Achalasia.

BACKGROUND/AIMS: Several studies have reported partial recovery of peristalsis in patients with achalasia after myotomy. The aim of our study is to analyze esophageal motility patterns after peroral endoscopic myotomy (POEM) and to assess the potential predictors and clinical impact of peristaltic recovery. METHODS: We performed a retrospective analysis of prospectively collected data of consecutive patients with achalasia undergoing POEM at a tertiary center. High-resolution manometry (HRM) studies prior to and after POEM were reviewed and the Chicago classification was applied. RESULTS: A total of 237 patients were analyzed. The initial HRM diagnoses were achalasia type I, 42 (17.7%); type II, 173 (73.0%); and type III, 22 (9.3%). Before POEM, peristaltic fragments were present in 23 (9.7%) patients. After POEM the Chicago classification diagnoses were: 112 absent contractility, 42 type I achalasia, 15 type II, 11 type III, 26 ineffective esophageal motility, 18 esophagogastric junction outflow obstruction, 10 fragmented peristalsis, and 3 distal esophageal spasm. Altogether 68 patients (28.7%) had signs of contractile activity, but the contractions newly appeared in 47 patients (47/214, 22.0%). Type II achalasia showed a trend for appearance of contractions (P = 0.097). Logistic regression analysis did not identify any predictors of peristaltic recovery. The post-POEM Eckardt score did not differ between patients with and without contractions nor did the parameters of timed barium esophagogram. CONCLUSIONS: More than 20% of achalasia patients have signs of partial recovery of esophageal peristalsis after POEM. It occurs predominantly in type II achalasia but the clinical relevance seems to be negligible.

Confocal Laser Endomicroscopy vs Biopsies in the Assessment of Persistent or Recurrent Intestinal Metaplasia/Neoplasia after Endoscopic Treatment of Barrett's Esophagus related Neoplasia.

BACKGROUND AND AIMS: Patients after endoscopic treatment of Barrett's esophagus (BE) related neoplasia (BORN) should enter endoscopic surveillance with biopsies to detect persistent or recurrent neoplasia or intestinal metaplasia (IM). Probe-based confocal laser endomicroscopy (pCLE) serves as a virtual biopsy and could replace standard biopsies. However, the role of pCLE in patients after endoscopic treatment of BORN has not been systematically assessed. The aim of this study was to compare pCLE with biopsies in detecting persistent/recurrent IM/neoplasia. METHODS: A single center, prospective and pathologist-blinded study was performed. Patients after endoscopic treatment of BORN (endoscopic resection or dissection, radiofrequency ablation) underwent surveillance endoscopy with pCLE followed by biopsies. RESULTS: A total of 56 patients were enrolled: initial diagnoses were low-grade dysplasia (LGD) in 24 patients (43%), high-grade dysplasia (HGD) in 12 patients (21%) and early adenocarcinoma (EAC) in 20 patients (36%). Only one patient (2%) experienced recurrent neoplasia (LGD), which was diagnosed by pCLE only. Twenty patients (35.7%) experienced persistent/recurrent IM, diagnosed by both pCLE and biopsies in 17 patients (17/30, 85%) and by pCLE only in 3 pts (3/30, 15%). Sensitivity, specificity, positive and negative predictive values to diagnose recurrent/persistent IM did not differ significantly between pCLE and biopsies; diagnostic accuracy was 100% (95%CI 93.6-100) for pCLE and 94.6 (95%CI 85.1-98.9%) for biopsies, p=0.25. In patients with IM detected by both tested methods, pCLE detected significantly more goblet cells (median 43 per patient) than biopsies (median 12 per patient), p=0.01. CONCLUSION: pCLE is at least as effective as standard biopsies in the detection of persistent/recurrent IM after endoscopic treatment of BORN.

Probe-based confocal laser endomicroscopy versus biopsies in the diagnostics of oesophageal and gastric lesions: A prospective, pathologist-blinded study.

BACKGROUND AND AIM: Probe-based confocal laser endomicroscopy (pCLE) provides real-time microscopic visualisation. Our aim was to compare the diagnostic accuracy of pCLE with standard biopsies in patients with visible oesophageal or gastric lesions. METHODS: This was a single-centre, prospective, pathologist-blinded study. Patients underwent high-resolution endoscopy, and lesions were examined by pCLE followed by standard biopsies. A definitive diagnosis was determined from resection specimen. Main outcomes were overall diagnostic accuracy, sensitivity, specificity and positive and negative predictive values. RESULTS: We examined 74 lesions in 67 patients. Definitive diagnoses revealed 34 malignant and 40 non-malignant lesions. pCLE diagnosis was correct in 89.2% (66/74), while diagnosis based on biopsy was correct in 85% (57/67; p = 0.6). The overall diagnostic accuracy of biopsies was 85% (76-94%) and that of pCLE was 89% (79-96%). pCLE correctly diagnosed malignant lesions, comprising oesophageal adenocarcinoma, oesophageal squamous-cell cancer or gastric adenocarcinoma, in 88.2% (30/34) of cases, while biopsy was correctly diagnosed in 75.9% (22/29; p = 0.3). Sensitivity and specificity to diagnose a malignant lesion were 75.9% (95% confidence interval (CI) 56-89%) and 100% (95% CI 90-100%) for biopsies and 88.2% (95% CI 72-97%) and 92% (95% CI 79-98%) for pCLE. No differences between biopsies and pCLE were found with regard to sensitivity, specificity to diagnose dysplastic and benign lesions (p > 0.2). CONCLUSION: pCLE provides satisfactory diagnostic accuracy comparable with standard biopsies in patients with oesophageal or gastric lesions. ClinicalTrials.gov identifier: NCT0292049).

Stenting to prevent esophageal stricture after circumferential endoscopic submucosal dissection: an experimental study.

Background and study aims Circular ESD (CESD) is a treatment option for patients with extensive early esophageal cancer. Its major drawback is the development of a stricture. Stenting may represent an attractive prevention strategy. We designed an experimental study to assess the effect of stents covered with acellular biomatrix (AB) and a drug-eluting stent. Materials and methods Thirty-five 35 pigs underwent CESD and were randomized into six groups: G1 (control), G2 (SEMS), G3 (SEMS + AB), G4 (SEMS + AB + steroid-eluting layer), G5 (biodegradable stent [BD]), G6 (BD + AB). SEMS were placed alongside the post-CESD defect, fixed and removed after 21 days. The main outcomes were stricture development, severity, and histopathology. Results Pigs with BD stents (G5, 6) experienced severe inflammation and hypergranulation without biodegradation, therefore, these groups were closed prematurely. Significant strictures developed in 29 of 30 pigs (96.7 %). The most severe stricture developed in G2 and G4 (narrowest diameter (mm) 8.5 ±â€Š3, 3 (G2) and 8.6 ±â€Š2.1 (G4) vs. 17 ±â€Š7.3 (G1) and 13.5 ±â€Š8.3 (G3); P  < 0.01. Signs of re-epithelization were present in 67 % and 71 % in G1 and G2 and in 100 % in G3 and G4. The most robust re-epithelization layer was present in G4. The inflammation was the most severe in G1 (mean score 2.3) and least severe in G4 (0.4). Conclusions Stenting did not effectively prevent development of post-CESD esophageal stricture. SEMS with AB resulted in improved re-epithelization and decreased stricture severity. Steroid-eluting SEMS suppressed inflammation. BD stents seem inappropriate for this indication.

First genotype-phenotype study reveals HLA-DQß1 insertion heterogeneity in high-resolution manometry achalasia subtypes.

Background: Achalasia is a primary oesophageal motility disorder. Although aetiology remains mainly unknown, a genetic risk variant, rs28688207 in HLA-DQB1, showed strong achalasia association suggesting involvement of immune-mediated processes in the pathogenesis. High-resolution manometry recognises three types of achalasia. The aim of our study was to perform the first genotype-phenotype analysis investigating the frequency of rs28688207 across the high-resolution manometry subtypes. Methods: This was a cross-sectional retrospective study. Achalasia patients from tertiary centres in the Czech Republic (n = 163), Germany (n = 114), Greece (n = 70) and controls were enrolled. All subjects were genotyped for the rs28688207 insertion. The Kruskal-Wallis test was used for the genotype-phenotype analysis. Results: A total of 347 achalasia patients (type I - 89, II - 210, III - 48) were included. The overall frequency of the rs28688207 was 10.3%. The distribution of the insertion was significantly different across the high-resolution manometry subtypes (p = 0.038), being most prevalent in type I (14.6%), followed by type II (9.5%) and III (6.3%). Conclusion: The frequency of the HLA-DQB1 insertion differs among high-resolution manometry achalasia subtypes. The insertion is most prevalent in type I, suggesting that immune-mediated mechanisms triggered by the insertion may play a more prominent role in the pathogenesis of this subtype.

Effect of ABCG2 on cytotoxicity of platinum drugs: interference of EGFP.

ATP-binding drug efflux transporters decrease intracellular concentrations of cytotoxic drugs, causing multidrug resistance in cancer. In this study, we examined possible interactions of ABCG2 transporter with platinum cytotoxic drugs. We demonstrate here an interference of platinum drugs with enhanced green fluorescence protein (EGFP) in the cellular models, where EGFP was employed as a reporter gene. Cytotoxicity of cisplatin (CIP), carboplatin (CAP) and oxaliplatin (OXP) was significantly lowered in MDCKII cells transfected with ABCG2 transporter and EGFP reporter. The IC(50) values in MDCKII-ABCG2 were 25.7, 164 and 165 microM for CIP, CAP and OXP, respectively, whereas IC(50) for the same cytostatics in MDCKII cells were as follows: 15.4, 133 and 50.3 microM. Addition of fumitremorgin C (FTC), a potent ABCG2 inhibitor, significantly suppressed the resistance of MDCKII-ABCG2 to OXP, suggesting that OXP interacts with ABCG2. However, FTC did not change the sensitivity of the cells to CIP and CAP. We assume that EGFP rather than ABCG2 causes the diminished toxicity of the platinum cytostatics in the transfected cells. This hypothesis was confirmed in human Hep2 cells expressing EGFP: using MTT test, IC(50) of 30.0, 247 and 27.9 microM were obtained for CIP, CAP and OXP, respectively, while 12.3, 106 and 20.5 microM were observed in the parent Hep2 cells. Employing neutral red cytotoxicity assay, similar data were obtained (IC(50) 7.73, 685 and 112 microM for CIP, CAP, and OXP, respectively, in the Hep2-EGFP cells and 1.65, 79.4 and 24.5 microM in the parent Hep2 cells). Caspase-3/7 assay revealed lower susceptibility of EGFP expressing Hep2 cells to apoptosis induced by CIP when compared to the parent cell line. We therefore conclude that EGFP in transfected cells interferes with cytotoxicity of platinum drugs by hindering the drug induced apoptosis and could cause misinterpretation of results obtained in cytotoxicity studies.

Radiofrequency ablation for Barrett's esophagus-related neoplasia.

Barrett's esophagus (BE) is a premalignant condition associated with increased risk of developing esophageal adenocarcinoma. In the past, BE patients with high-grade intraepithelial neoplasia (IEN) or early adenocarcinoma (EAC) were indicated for esophagectomy. With the recent advance in endoscopy, endoscopic techniques have surpassed esophagectomy in the treatment of Barrett's esophagus-related neoplasia and minimized the treatment-related morbidity. Patients with IEN are candidates for endoscopic treatment - endoscopic mucosal resection (ER) of visible lesions and/or ablation therapy of flat Barrett's mucosa. ER combined with radiofrequency ablation (RFA) is now considered as a gold standard for treatment of patients with early Barrett's cancer. RFA is currently the most effective method of ablation used in the treatment of low-grade intraepithelial neoplasia/high-grade intraepithelial neoplasia without visible lesions and for ablation of residual Barrett's mucosa following ER/ESD of EAC or HGIN aiming to achieve complete eradication of Barrett's surface and thus, decreasing the risk of recurrent dysplasia or cancer. The rates of complete remission of neoplasia and metaplasia after completion of endoscopic treatment are 81-92.6% and 75-88.2%, respectively. The aim of this article is to review the principles, techniques, indications, efficacy and safety of this ablative method and surveillance of patients after successful treatment with RFA.