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Background: Bacterial antibiotic resistance changes over time depending on multiple factors, therefore, it is essential to monitor the susceptibility trends to reduce the resistance impact on the effectiveness of various treatments. Objective: To conduct a time-trend analysis of Helicobacter pylori resistance to antibiotics in Europe. Methods: The international prospective European Registry on Helicobacter pylori Management (Hp-EuReg) collected data on all infected adult patients diagnosed with culture and antimicrobial susceptibility testing positive results that were registered at AEG-REDCap e-CRF until December 2020. Results: Overall, 41,562 patients were included in the Hp-EuReg. Culture and antimicrobial susceptibility testing were performed on gastric biopsies of 3974 (9.5%) patients, of whom 2852 (7%) were naive cases included for analysis. The number of positive cultures decreased by 35% from the period 2013–2016 to 2017–2020. Concerning naïve patients, no antibiotic resistance was found in 48% of the cases. The most frequent resistances were reported against metronidazole (30%), clarithromycin (25%), and levofloxacin (20%), whereas resistances to tetracycline and amoxicillin were below 1%. Dual and triple resistances were found in 13% and 6% of the cases, respectively. A decrease (p &lt, 0.001) in the metronidazole resistance rate was observed between the 2013–2016 (33%) and 2017–2020 (24%) periods. Conclusion: Culture and antimicrobial susceptibility testing for Helicobacter pylori are scarcely performed (&lt, 10%) in Europe. In naïve patients, Helicobacter pylori resistance to clarithromycin remained above 15% throughout the period 2013–2020 and resistance to levofloxacin, as well as dual or triple resistances, were high. A progressive decrease in metronidazole resistance was observed.

Introduction: Few data on the diagnostic performance of serological tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are currently available. We evaluated sensitivity and specificity of five different widely used commercial serological assays for the detection of SARS-CoV-2–specific IgG, IgM, and IgA antibodies using reverse transcriptase-PCR assay in nasopharyngeal swab as reference standard test.Methods: A total of 337 plasma samples collected in the period April–June 2020 from SARS-CoV-2 RT-PCR positive (n = 207) and negative (n = 130) subjects were investigated by one point-of-care lateral flow immunochromatographic assay (LFIA IgG and IgM, Technogenetics) and four fully automated assays: two chemiluminescence immunoassays (CLIA-iFlash IgG and IgM, Shenzhen YHLO Biotech and CLIA-LIAISON® XL IgG, DiaSorin), one electrochemiluminescence immunoassay (ECLIA-Elecsys® total predominant IgG, Roche), and one enzyme-linked immunosorbent assay (ELISA IgA, Euroimmune).Results: The overall sensitivity of all IgG serological assays was >80% and the specificity was >97%. The sensitivity of IgG assays was lower within 2 weeks from the onset of symptoms ranging from 70.8 to 80%. The LFIA and CLIA-iFlash IgM showed an overall low sensitivity of 47.6 and 54.6%, while the specificity was 98.5 and 96.2%, respectively. The ELISA IgA yielded a sensitivity of 84.3% and specificity of 81.7%. However, the ELISA IgA result was indeterminate in 11.7% of cases.Conclusions: IgG serological assays seem to be a reliable tool for the retrospective diagnosis of SARS-CoV-2 infection. IgM assays seem to have a low sensitivity and IgA assay is limited by a substantial rate of indeterminate results.

In questo articolo viene illustrata la possibilità di generazione di ceppi probiotici ricombinanti in grado di esprimere molecole con vantaggiose proprietà farmacologiche. Attraverso studi effettuati su modelli murini prima e su esseri umani poi è stato sperimentato l’uso di batteri geneticamente modificati per il rilascio di proteine terapeutiche nel trattamento continuativo delle malattie croniche intestinali a partire dal trattamento, con ceppi ricombinanti di Lactobacillus lactis, del morbo di Crohn, di malattie croniche intestinali, coliti acute e croniche. Sono altresì stati indagati gli effetti di molecole bioattive quali allergeni, enzimi digestivi e anticorpi a singola catena ottenuti usando batteri produttori di acido lattico in candidosi vaginali, carie dentali, allergie, malattie autoimmuni, tumori indotti da HPV e insufficienza pancreatica. La superficie cellulare del Lactobacillus acidophilus è infine stata utilizzata come potenziale strategia per il trattamento di patologie infiammatorie intestinali.

Background & Aims: H. pylori eradication with standard therapies is decreasing worldwide, mainly because of increased primary antibiotic resistance rates. We aimed to assess primary resistance in H. pylori isolates towards the most used antibiotics in clinical practice. methods: The study enrolled consecutive, dyspeptic, adult patients, never treated for H. pylori, who had underwent upper endoscopy. Gastric biopsies were taken for standard histology, and two further antral biopsies were used for H. pylori culture. Minimal inhibitory concentrations (MIC) ≥1, ≥8 and ≥1 mg/L were used as break point for clarithromycin, metronidazole, and levofloxacin resistance, respectively. Results: Bacterial culture was successful in 145 (94%) out of 154 infected patients. Resistance towards at least one antibiotic was detected in 111 (76.6%) isolated, and multiple antibiotic resistance in 35.2% of cases. Primary resistance towards clarithromycin, metronidazole, and levofloxacin was detected in 51 (35.2%), 86 (59.3%), and in 32 isolated (22.1%), respectively. Levofloxacin resistance was significantly associated with the male sex (OR: 11.3, 95% CI = 1.2-103; P = 0.03), whilst females were at a higher risk of being infected with bacterial strains harbouring a double clarithromycin and metronidazole resistance (OR: 4.9, 95% CI = 1.2-19.8, P = 0.02). Conclusion: Our data indicate a very high primary resistance rate towards the most used antibiotics in H. pylori isolates. The efficacy of standard eradication therapies is expected to further decrease

Primary clarithromycin resistance is the main factor affecting the efficacy of Helicobacter pylori therapy. This study aimed: (i) to assess the concordance between phenotypic (culture) and genotypic (real-time PCR) tests in resistant strains; (ii) to search, in the case of disagreement between the methods, for point mutations other than those reported as the most frequent in Europe; and (iii) to compare the MICs associated with the single point mutations. In order to perform real-time PCR, we retrieved biopsies from patients in whom H. pylori infection was successful diagnosed by bacterial culture and clarithromycin resistance was assessed using the Etest. Only patients who had never been previously treated, and with H. pylori strains that were either resistant exclusively to clarithromycin or without any resistance, were included. Biopsies from 82 infected patients were analysed, including 42 strains that were clarithromycin resistant and 40 that were clarithromycin susceptible on culture. On genotypic analysis, at least one of the three most frequently reported point mutations (A2142C, A2142G and A2143G) was detected in only 23 cases (54.8 %), with a concordance between the two methods of 0.67. Novel point mutations (A2115G, G2141A and A2144T) were detected in a further 14 out of 19 discordant cases, increasing the resistance detection rate of PCR to 88 % (P

Current guidelines recommend that all patients with documented H. pylori infection should be treated with an appropriate antibacterial therapy. Clarithromycin-based regimens are commonly used as a first line therapy in H. pylori positive patients, however soon after the introduction of clarithromycin-based therapies, treatment failures associated with resistance to clarithromycin were reported. In this study, we evaluated the feasibility of using a non-invasive sample type, stool, to detect the presence of H. pylori by molecular methods while concurrently detecting mutations associated with the resistance to clarithromycin. The sensitivity for H. pylori detection by PCR was 93.8% compared to composite reference methods with gastric tissue biopsy. Out of 213 true positives that were sequenced, 36.2% showed point mutations associated with CLA resistance (A2142C, A2142G, A2143G). The correlation of sequencing and PCR was 98%. The correlation of sequencing and eradication of the infection was 86%. The results of this test may be used as a tool for guiding treatment of H. pylori infection.

Rapid diagnostic tools for Helicobacter pylori are important in endoscopy. To assess the accuracy of a new 5-min rapid urease test (UFT300, ABS Cernusco, sul Naviglio, Italy) compared with the 1-h Pyloritek (Serim Laboratories, Elkhart, IN) and the 24-h CLO test (Kimberly- Clark Ballard Medical Products, Roswell, GA), consecutive dyspeptic patients referred to our unit for endoscopy were prospectively studied. All patients underwent a 13C-urea-breath test, histology and the UFT300 (ABS; Cernusco, sul Naviglio, Italy). Two additional rapid urease tests were performed. Patients were deemed infected when both 13C-UBT and histology were positive. Rapid urease tests were read at 1, 5, and 60 min, respectively. Of the 375 enrolled patients, 45.3% were infected with H. pylori. The sensitivity of the new 5-min rapid urease test 300 was 90.3, 94.5, and 96.2% at 1, 5, and 60 min, respectively (specificity 100%). The Pyloritek and the new 5-min rapid urease test were comparable, but the CLO test was not reliable at 5 and 60 min. In conclusion, the new 5-min rapid urease test is comparable to the Pyloritek test, but the CLO test is significantly less sensitive at early time points. Reading the test results at 1 min may increase falsenegative results with decreasing sensitivity.

Tra i trilioni di batteri componenti la microflora del tratto digerente, le specie Fusobacterium varium e nucleatum e Bacteroides fragilis enterotossigenico (ETBF) hanno recentemente attirato l’attenzione della comunità scientifica per il possibile coinvolgimento nelle malattie infiammatorie croniche dell’intestino, in particolare nella colite ulcerosa (CU) e nella cancerogenesi colica. Il genere Fusobacterium comprende 13 specie di batteri Gram-negativi, isolate sia nell’uomo che negli animali. Il Bacteroides fragilis è un componente minore della microflora intestinale ma è il batterio anaerobio che più frequentemente induce malattia. Il B. fragilis comprende tre ceppi maggiori di cui uno enterotossigenico. Clinicamente l’ETBF è correlato a diarrea secretoria, ma vi sono sempre più evidenze circa la sua correlazione anche alla eziopatogenesi delle CU e del cancro del colon. Un elemento centrale per la patogenicità dell’ETBF è la produzione della tossina. Basandoci sulle conoscenze già acquisite, lo scopo futuro dei nostri studi sarà di ottenere sempre più informazioni circa la prevalenza, la patogenicità e la sensibilità ai chemoterapici di queste specie batteriche

The use of probiotics in the form of whole bacteria to achieve health benefits in humans is evolving by the development of recombinant probiotic bacteria as carriers of specific genes achieving a probiotic effect. Studies have demonstrated that bacteria carrying either the gene for IL-10 or for trefoil factors when given in an animal model or as part of a human trial can ameliorate inflammatory conditions of the colon. Such an approach has the advantages of a long-term delivery, the potential for fewer side effects and utility in many other conditions including other autoimmune diseases, dental caries, candidiasis and allergies. Other health benefits are also under investigation in relation to altering the fatty acid composition of adipose tissue by colonizing the intestine with a bacterium carrying the gene involved in fatty acid metabolism. Not only is the lean body mass advantageously affected but the enzyme is active in inducing apoptosis in cancer cells. Benefits may also be obtained not only by adding a gene but deletion of a gene from a bacterium which modulates the production of pro-inflammatory cytokines or may make the probiotic bacterium act as a more effective delivery system by enhancing colonization

Studi sperimentali indicano che i batteri filamentosi segmentati (BFS) possono riassumere le risposte immunitarie fondamentali, riguardanti in particolare le cellule della linea Th17 e l’attività regolatoria delle cellule della linea T. La recente descrizione delle sequenze genomiche complete del DNA dei BFS di topo e ratto e il confronto tra esse consente di realizzare negli esseri umani studi quali-quantitativi riguardanti tali batteri anaerobi, attualmente non colturabili. L’analisi comparativa delle sequenze del 16S rRNA dei BFS di topo e ratto suggerisce l’esistenza di regioni altamente conservate che possono rappresentare dei bersagli molecolari specifici, potenzialmente utili per sviluppare sonde PCR per lo studio dei BFS negli esseri umani. Questi strumenti molecolari possono essere di inestimabile valore per valutare il possibile ruolo giocato dai BFS nella fisiologia del sistema immunitario, così come il loro potenziale coinvolgimento nell’infiammazione cronica e nelle malattie autoimmuni umane

Colonoscopy workload for endoscopy services in Western countries is increasing markedly because of the implementation of faecal occult blood-based mass screening programmes against colorectal cancer (CRC). We therefore explored the possibility of using a combination of faecal tests to prioritize the access to colonoscopy with criteria other than symptoms and/or time of referral.We tested a combination of faecal tests [immunochemical faecal occult blood test (i-FOBT), M2-PK, calprotectin] as markers for advanced neoplasia in a selected series of patients requiring colonoscopy for the suspicion of CRC. All the tests were performed in a 1-day stool sample of patients aged 50-80 years, without any dietary restriction, before colonoscopy.A total of 280 patients' stool single samples were analysed. Forty-seven patients had CRC and 85 patients had one or more advanced adenoma(s) at colonoscopy/histology. CRCs were associated with a highly significant increase (P0.001) in faecal tumour M2-PK (mean 24.2 kU/l), which correlated with Dukes' staging. For CRC detection, i-FOBT was the test with the highest specificity and positive predictive value (0.89 and 0.53), whereas M2-PK had the highest sensitivity and negative predictive value (0.87 and 0.96). Calprotectin showed performance similar to M2-PK in terms of sensitivity and negative predictive value (0.93), but had lower specificity (0.39). The best combination of tests to predict the risk of CRC in this series was i-FOBT+M2-PK, as in patients showing positivity to both markers, the risk of cancer was as high as 79%.The combination of i-FOBT and M2-PK is a sensitive tool in clinical practice for the appropriate management of waiting lists for colonoscopy, as it allows the classification of patients into different degrees of priority for investigation, according to their foreseeable risk of CRC.

I batteri probiotici hanno dimostrato di avere effetti terapeutici nelle infezioni, nelle malattie infiammatorie e in quelle allergiche. I probiotici sono comunemente definiti come microrganismi vivi preferibilmente di origine umana che, se ingeriti in un numero sufficiente, esercitano specifici benefici per la salute; tuttavia le vie impiegate da questi batteri sono poco conosciute e i dettagli molecolari alla base di questi percorsi rimangono in gran parte ignoti. Capire come i probiotici esercitino i loro effetti benefici è fondamentale per la definizione di criteri di selezione per le strategie farmacobiotiche in specifiche condizioni cliniche.

Recenti evidenze indicano che i batteri filamentosi segmentati (BFS), Candidatus arthromitus, svolgono un ruolo peculiare in diversi aspetti della maturazione del sistema immunitario, tra cui le risposte delle cellule T; risulta dunque particolarmente rilevante rivedere le conoscenze su questi batteri e sul loro rapporto con il sistema immunitario e indagare i loro aspetti morfologici. In questi organismi si possono distinguere una forma proliferativa e una forma vegetativa. Queste diverse forme hanno ruoli differenti nel ciclo vitale: la forma proliferativa permette una rapida crescita degli organismi, mentre la forma vegetativa consente l’adesione dei BFS all’epitelio follicolare. Abbiamo inoltre posto particolare attenzione alle modalità di interazione tra i BFS e le cellule epiteliali dell’ileo terminale, al fine di comprendere meglio la relazione unica tra questi batteri e il sistema immunitario.