Proton pump inhibitor effect on esophageal protein signature of eosinophilic esophagitis, prediction, and evaluation of treatment response.

BACKGROUND: Recently, we have identified a dysregulated protein signature in the esophageal epithelium of eosinophilic esophagitis (EoE) patients including proteins associated with inflammation and epithelial barrier function; however, the effect of proton pump inhibitor (PPI) treatment on this signature is unknown. Herein, we used a proteomic approach to investigate: (1) whether PPI treatment alters the esophageal epithelium protein profile observed in EoE patients and (2) whether the protein signature at baseline predicts PPI response. METHODS: We evaluated the protein signature of esophageal biopsies using a cohort of adult EoE (n = 25) patients and healthy controls (C) (n = 10). In EoE patients, esophageal biopsies were taken before (pre) and after (post) an 8-week PPI treatment, determining the histologic response. Eosinophil count PostPPI was used to classify the patients: ≥15 eosinophils/hpf as non-responders (non-responder) and < 15 eosinophils/hpf as responders (R). Protein signature was determined and differentially accumulated proteins were characterized to identify altered biological processes and signaling pathways. RESULTS: Comparative analysis of differentially accumulated proteins between groups revealed common signatures between three groups of patients with inflammation (responder-PrePPI, non-responder-PrePPI, and non-responder-PostPPI) and without inflammation (controls and responder-PostPPI). PPI therapy almost reversed the EoE specific esophageal protein signature, which is enriched in pathways associated with inflammation and epithelial barrier function, in responder-PostPPI. Furthermore, we identified a set of candidate proteins to differentiate responder-PrePPI and non-responder-PrePPI EoE patients before treatment. CONCLUSION: These findings provide evidence that PPI therapy reverses the alterations in esophageal inflammatory and epithelial proteins characterizing EoE, thereby providing new insights into the mechanism of PPI clinical response. Interestingly, our results also suggest that PPI response could be predicted at baseline in EoE.

Proteomic analysis of the esophageal epithelium reveals key features of eosinophilic esophagitis pathophysiology.

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic non-IgE-mediated allergic disease of the esophagus. An unbiased proteomics approach was performed to investigate pathophysiological changes in esophageal epithelium. Additionally, an RNAseq-based transcriptomic analysis in paired samples was also carried out. METHODS: Total proteins were purified from esophageal endoscopic biopsies in a cohort of adult EoE patients (n = 25) and healthy esophagus controls (n = 10). Differentially accumulated (DA) proteins in EoE patients compared to control tissues were characterized to identify altered biological processes and signaling pathways. Results were also compared with a quantitative proteome dataset of the human esophageal mucosa. Next, results were contrasted with those obtained after RNAseq analysis in paired samples. Finally, we matched up protein expression with two EoE-specific mRNA panels (EDP and Eso-EoE panel). RESULTS: A total of 1667 proteins were identified, of which 363 were DA in EoE. RNA sequencing in paired samples identified 1993 differentially expressed (DE) genes. Total RNA and protein levels positively correlated, especially in DE mRNA-proteins pairs. Pathway analysis of these proteins in EoE showed alterations in immune and inflammatory responses for the upregulated proteins, and in epithelial differentiation, cornification and keratinization in those downregulated. Interestingly, a set of DA proteins, including eosinophil-related and secreted proteins, were not detected at the mRNA level. Protein expression positively correlated with EDP and Eso-EoE, and corresponded with the most abundant proteins of the human esophageal proteome. CONCLUSIONS: We unraveled for the first time key proteomic features involved in EoE pathogenesis. An integrative analysis of transcriptomic and proteomic datasets provides a deeper insight than transcriptomic alone into understanding complex disease mechanisms.

[Diagnostic and prognostic power of biomarkers to improve the management of community acquired pneumonia in the emergency department]. / Poder diagnóstico y pronóstico de los biomarcadores para mejorar el manejo de la neumonía adquirida en la comunidad en los servicios de urgencias.

OBJECTIVES: To analyse the usefulness and performance of several biomarkers [C-reactive protein (CRP), mid-regional pro-adrenomedullin (MR-proADM), procalcitonin (PCT)] and lactate in predicting short- and medium-term mortality compared with the prognostic severity scales (PSS) usually employed for community-acquired pneumonia (CAP) and in assessing the aetiological suspicion of infection by Streptococcus pneumoniae and bacteraemia. METHODS: Observational, prospective and analytical study was conducted on patients who were diagnosed with CAP in our emergency department (ED). The data collected included socio-demographic and comorbidity variables, Charlson index, priority level according to the Spanish Triage System (STS), stage in the Pneumonia Severity Index (PSI) and in the CURB-65 (confusion, urea, respiratory rate, blood pressure and age ≥65years), criteria of severe CAP, microbiological studies, and biomarkers determinations. The patients were followed-up for 180days to calculate the prognostic power and the diagnostic performance for bacteraemia and aetiology. RESULTS: A total of 127patients were finally enrolled in the study. The 30-day mortality was 10.3% (13), and 22.6% (28) at 180 days. Blood cultures were positive in 29 patients (23%) and S.pneumoniae was identified as the responsible pathogen in 28 cases (22.2%). The area under the ROC curve (AUC-ROC) for lactate and MR-proADM to predict 30-day mortality was 0.898 (95%CI: 0.824-0.973; P<.0001) and 0.892 (95%CI: 0.811-0.974; P<.0001), respectively, and for MR-proADM at 180 days it was 0.921 (95%CI: 0.874-0.968; P<.0001). The AUC-ROC for PCT to predict bacteraemia was 0.952 (95%CI: 0.898-1.000; P<.0001) and, considering a cut-off value ≥0.95ng/ml, the negative predictive value (NPV) and the likelihood ratio (LR+) were 97.8% and 9.03, respectively. Using a PCT cut-off value >0.85ng/ml, the NPV and the LR+ were 96.6% and 5.89%, respectively, to predict a S.pneumoniae infection. CONCLUSIONS: MR-proADM and lactate showed a similar or even better performance for 30-day intra-hospital mortality than PSI, CURB-65, STS and CAP severity criteria in patients diagnosed with CAP (P>.05). Furthermore, the MR-proADM capacity to predict 180-day mortality was higher than PSS and the rest of biomarkers (P>.05), and its AUC-ROC increased if it was used in combination with PSI, CURB65 and STS. The determination of PCT has a remarkable diagnostic performance to rule out bacteraemia and to orientate the aetiology towards a S.pneumoniae infection.

Detection capacity of small intestine bacterial or methanogen overgrowth by lactose and fructose breath testing in the adult population.

Objectives: Exhaled breath tests (BTs) are the main diagnostic method for fructose and lactose malabsorption/intolerance (FI and LI, respectively) and for detecting small intestine bacterial or methanogen overgrowth (SIBO/IMO). Although FI/LI-BTs may provide evidence of the presence of SIBO/IMO, there is limited literature evaluating their reliability for this purpose. The objective of this study was to assess the sensitivity and specificity of FI/LI-BTs in detecting SIBO and their concordance with SIBO-BTs in the identification of IMO. Methods: In this retrospective observational study, FI/LI-BTs and SIBO-BTs performed in the same patients within a period of 6 weeks were selected from 652 gas chromatography-based BTs. Results: A total of 146 BTs from 67 eligible adult patients were identified. LI-BTs had higher specificity than FI-BT in detecting SIBO (93.8 % vs. 72.7 %). In contrast, FI-BTs showed higher sensitivity (60.0 % vs. 28.6 %) as FI was more frequently established in SIBO-positive patients (70 % vs. 29 %). With regard to IMO, concordance with LI-BT was 100 %, with a 27 % of false negatives on FI-BTs. Conclusions: Findings suggestive of SIBO or IMO on LI-BTs were highly consistent with those of SIBO-BTs. In contrast, the rate of false positives for SIBO and the rate of false negative for IMO on FI-BTs was 27 % in both cases.

Biological variation and reference change values of common clinical chemistry and haematologic laboratory analytes in the elderly population.

BACKGROUND: Biological variation (BV) and reference change values (RCVs) have been widely described for the general population, but the use of these data derived from adults in the elderly population is a controversial issue. We determined the within- and between-subject BV and RCV in both elderly and young people and compared them with previously published analyses. METHODS: Samples were collected from 135 volunteers over 80 years of age at weekly intervals over 4 weeks. Eighteen biochemical and eight haematological analytes were measured. The Fraser and Harris methods were used to calculate the components of BV and RCV. To perform a comparative analysis, a reference group of 118 young subjects was studied under the same conditions. RESULTS: The obtained coefficients of BV showed statistical differences in many cases, but in general, both the elderly and young patient data fall within the ranges previously described for the general population. The indexes of individuality for the analytes investigated did not exceed 1.4 in any case and were <0.6 for some analytes. The RCVs derived from elderly subjects were similar to those published in the young population, both in healthy and diseased individuals. CONCLUSIONS: The strong individuality observed supports the preferential use of RCVs rather than population-based reference intervals in elderly people. For most of the analytes studied, data from the young population can be applied to elderly people, but the specific elderly coefficients of BV and RCVs are a recommended option.

Differences between childhood- and adulthood-onset eosinophilic esophagitis: An analysis from the EoE connect registry.

BACKGROUND: Direct comparisons of childhood- and adulthood-onset eosinophilic esophagitis (EoE) are scarce. AIM: To compare disease characteristics, endoscopic and histological features, allergic concomitances and therapeutic choices across ages. METHODS: Cross-sectional analysis of the EoE CONNECT registry. RESULTS: The adulthood-onset cohort (those diagnosed at ≥18y) comprised 1044 patients and the childhood-onset cohort (patients diagnosed at <18 y), 254. Vomiting, nausea, chest and abdominal pain, weight loss, slow eating and food aversion were significantly more frequent in children; dysphagia, food bolus impaction and heartburn predominated in adults. A family history of EoE was present in 16% of pediatric and 8.2% of adult patients (p<0.001). Concomitant atopic diseases did not vary across ages. Median±IQR diagnostic delay (years) from symptom onset was higher in adults (2.7 ± 6.1) than in children (1 ± 2.1; p<0.001). Esophageal strictures and rings predominated in adults (p<0.001), who underwent esophageal dilation more commonly (p = 0.011). Inflammatory EoE phenotypes were more common in children (p = 0.001), who also presented higher eosinophil counts in biopsies (p = 0.015) and EREFS scores (p = 0.017). Despite PPI predominating as initial therapy in all cohorts, dietary therapy and swallowed topical corticosteroids were more frequently prescribed in children (p<0.001). CONCLUSIONS: Childhood-onset EoE has differential characteristics compared with adulthood-onset, but similar response to treatment.

Evaluation of a New Monoclonal Chemiluminescent Immunoassay Stool Antigen Test for the Diagnosis of Helicobacter pylori Infection: A Spanish Multicentre Study.

The stool antigen test (SAT) represents an attractive alternative for detection of Helicobacter pylori. The aim of this study was to assess the accuracy of a new SAT, the automated LIAISON® Meridian H. pylori SA based on monoclonal antibodies, compared to the defined gold standard 13C-urea breath test (UBT). This prospective multicentre study (nine Spanish centres) enrolled patients ≥18 years of age with clinical indication to perform UBT for the initial diagnosis and for confirmation of bacterial eradication. Two UBT methods were used: mass spectrometry (MS) including citric acid (CA) or infrared spectrophotometry (IRS) without CA. Overall, 307 patients (145 naïve, 162 with confirmation of eradication) were analysed. Using recommended cut-off values (negative SAT < 0.90, positive ≥ 1.10) the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 67%, 97%, 86%, 92% and 91%, respectively, obtaining an area under the receiver operating characteristic (ROC) curve (AUC) of 0.85. Twenty-eight patients, including seven false positives and 21 false negatives, presented a discordant result between SAT and UBT. Among the 21 false negatives, four of six tested with MS and 11 of 15 tested with IRS presented a borderline UBT delta value. In 25 discordant samples, PCR targeting H. pylori DNA was performed to re-assess positivity and SAT accuracy was re-analysed: sensitivity, specificity, positive predictive value, negative predictive value, accuracy and AUC were 94%, 97%, 86%, 99%, 97% and 0.96, respectively. The new LIAISON® Meridian H. pylori SA SAT showed a good accuracy for diagnosis of H. pylori infection.

A multicentre analysis of four low-density lipoprotein cholesterol direct assays in samples with extreme high-density lipoprotein cholesterol concentrations.

BACKGROUND: Although LDL-C has been traditionally estimated using the Friedewald formula (FF), several direct homogeneous assays have been developed to overcome the limitations of this formula and the complicated manual procedure required in the reference method. However, several differences have been reported between these assays in certain situations. METHODS: Two groups of 105 samples with extreme low and high HDL-C concentrations were processed, employing four different instruments and with the reagents for total cholesterol, triglycerides, HDL-C and LDL-C provided by the distinct manufacturers. RESULTS: Statistical tests indicated important differences between HDL-C and LDL-C homogeneous methods. Poor correlation, significant bias and high discrepancy in cardiovascular disease risk classification were observed for LDL-C direct assays in the low HDL-C group, whereas better results were obtained when comparing LDL-C levels estimated with the FF. In contrast, three of the four instruments generated LDL-C direct results with a good agreement in the high HDL-C group, even though an appreciable misclassification percentage in risk categories must be taken into account. CONCLUSIONS: Our results indicate that extreme low or high HDL-C levels can represent a non-previously described source of variation between commercially available LDL-C homogeneous assays.

[Ability of procalcitonin to predict bacteremia in patients with community acquired pneumonia]. / Capacidad de la procalcitonina para predecir bacteriemia en pacientes con neumonía adquirida en la comunidad.

BACKGROUND AND OBJECTIVE: To analyze the usefulness and ability of procalcitonin (PCT) to predict the presence of bacteremia in patients with community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae (S. pneumoniae) or other bacteria. PATIENTS AND METHOD: This is an observational, prospective and descriptive study involving patients who were diagnosed with CAP in our Emergency Department. Data collected included socio-demographic and comorbidity variables, Charlson index, stage in the Pneumonia Severity Index and criteria of severe NAC, microbiologic studies and biomarker determinations (PCT and C reactive protein). The follow-up was carried out during 30 days to calculate the predictive power and the diagnostic performance for bacteremia caused or not by S. pneumoniae. RESULTS: Four hundred and seventy-four patients were finally included in the study. Blood cultures were positive in 85 individuals (17.9%) and S. pneumoniae was identified as the responsible pathogen in 75 of them (88.4%) (in 5 cases together with another agent). The area under the Receiver Operating Characteristic curve for PCT to predict bacteremia (caused by S. pneumoniae or not) was 0.988 (95% confidence interval 0.908-0.995; P<.001) and, considering a cut-off value≥0.95ng/mL, the negative predictive value and the positive likelihood ratio were>98% and>10, respectively. The most frequently isolated serotypes of S. pneumoniae were 19A, 7F, 1 and 3. The highest mean levels of PCT were found in serotypes 7F, 19A, 3 and 1, which showed statistically significant differences with regard to the others serotypes considered (P=.008). Serotypes associated with the highest percentage of severe sepsis-septic shock, 30-days mortality and multi-lobe or bilateral affection were 3, 1 and 19A; 1, 3 and 19A; and 3, 19A and 6A, respectively. CONCLUSIONS: PCT had a remarkable diagnostic ability to discard or suspect bacteremia and to guide the etiology of CAP caused by S. pneumoniae. Serotypes 1, 3, 19A and 7F showed greater frequency, systemic inflammatory response and clinical severity.

A proposed reference change value for an IgA anti-tissue transglutaminase immunoassay to improve interpretation of serial results in celiac patients.

BACKGROUND: Celiac disease (CD) is an autoimmune disorder caused by an inappropriate immunological response to gluten ingestion in genetically susceptible individuals. IgA anti-tissue transglutaminase (tTG) antibodies have been widely employed as a specific biochemical marker for CD. Recent studies have also shown its usefulness in evaluating patient compliance with a gluten-free diet. METHODS: A group of 28 subjects with CD was selected for the study. Each fulfilled the requirement of a gluten-free diet for more than one year. IgA anti-tTG determination was performed every two months for half a year. These data were used to estimate the biological variation (BV) of IgA anti-tTG in celiac patients and to calculate the reference change value (RCV). RESULTS: The within-subject biological variation (CVI) and between-subject biological variation (CV(G)) were 19.2% and 75.6%, respectively, and the index of individuality was 0.25. The RCV calculated using these data together with our analytical imprecision (5.7%) was 55.5% for a 95% level of significance. CONCLUSIONS: We have determined for the first time the BV and the RCV for IgA anti-tTG in a celiac population. This value and the probability curve generated from our data could be a valuable tool for monitoring patients' adherence to dietary treatment.

Extreme concentrations of high density lipoprotein cholesterol affect the calculation of low density lipoprotein cholesterol in the Friedewald formula and other proposed formulas.

OBJECTIVES: To investigate the effect of extreme levels of high density lipoprotein cholesterol (HDL-C) in the calculation of low density lipoprotein cholesterol (LDL-C) using Friedewald's formula (FF) and other formulas proposed recently. DESIGN AND METHODS: Lipoprotein profile was performed in 2603 samples with HDL-C ≤ 20 mg/dL and 1953 samples with HDL-C ≥ 100 mg/dL. RESULTS: Wilcoxon's and Student's t-tests showed significant differences (p<0.001) between calculated LDL-C by different formulas and direct determination in the two groups of HDL-C values. Passing-Bablok regression and Bland-Altman plot showed disagreement for the four formulas studied, except for Vujovic formula in the HLD-C ≥ 100 mg/dL group. CONCLUSIONS: Our results suggested that none of the formulas under analysis should be used for estimating LDL-C in samples with extreme HDL-C concentrations due to absence of statistical correlation with LDL-C direct measurement.