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BACKGROUND& AIMS: Although antithrombotic agents could increase the risk of postpolypectomy bleeding, interruption of these agents also increases the risk of thromboembolism (TE). We assessed the risks of postcolonoscopy TE events and their association with the interruption of antithrombotic agents. METHODS: This was a retrospective cohort study including consecutive patients undergoing colonoscopy between January 2016 and March 2021. We determined the rates of postcolonoscopy TE events in patients taking various antithrombotic agents (with or without interruption), and in different patient groups according to indications for colonoscopy, underlying TE, and bleeding risks. RESULTS: Of the 6220 patients, 1755 (28.2%) were on antithrombotics. Overall, 20 patients (0.32%) developed TE events, and 25 (0.80%) of 3134 patients with polypectomy experienced major episodes of bleeding. Among all patients on antithrombotic agents, the highest rates of TE events were observed in patients on dual-antiplatelet therapy (4.65%; adjusted odds ratio [aOR], 28.0; 95% CI, 3.77-142.1) and clopidogrel (2.78%; aOR, 12.2; 95% CI, 2.10-57.0), compared with 0.11% among those not on antithrombotics. In patients interrupting anti-thrombotic agents, the risk of TE was increased compared to those on no agent as follows: stopping 2 or more antithrombotic agents (4.55%; aOR, 22.5; 95% CI, 1.09-158.0), monotherapy with clopidogrel (3.06%; aOR, 15.5; 95% CI, 2.86-69.6), warfarin (1.33%; aOR, 6.96; 95% CI, 1.14-33.5), or direct-acting oral anticoagulants (0.87%; aOR, 6.23; 95% CI, 1.22-26.8). Having an underlying high TE risk (aOR, 16.8; 95% CI, 6.33-46.6) was associated with higher postcolonoscopy TE events. CONCLUSIONS: The risk of post-colonoscopy thromboembolic events is low. However, the temporary interruption of antithrombotic agents, particularly stopping 2 or more agents, clopidogrel, warfarin, or direct-acting oral anticoagulants was associated with higher postcolonoscopy TE events, particularly in high-risk patients.
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Colonoscopía , Tromboembolia , Warfarina , Humanos , Anticoagulantes/efectos adversos , Clopidogrel , Estudios de Cohortes , Inhibidores del Factor Xa , Fibrinolíticos/efectos adversos , Hemorragia/inducido químicamente , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Tromboembolia/epidemiología , Tromboembolia/etiología , Colonoscopía/efectos adversosRESUMEN
BACKGROUND AND AIMS: Linked color imaging (LCI) is a newly available image-enhanced endoscopy (IEE) system that emphasizes the red mucosal color. No study has yet compared LCI with other available IEE systems. Our aim was to investigate polyp detection rates using LCI compared with narrow-band imaging (NBI). METHODS: This is a prospective randomized tandem colonoscopy study. Eligible patients who underwent colonoscopy for symptoms or screening/surveillance were randomized in a 1:1 ratio to receive tandem colonoscopy with both colonoscope withdrawals using LCI or NBI. The primary outcome was the polyp detection rate. RESULTS: Two hundred seventy-two patients were randomized (mean age, 62 years; 48.2% male; colonoscopy for symptoms, 72.8%) with 136 in each arm. During the first colonoscopy, the polyp detection rate (71.3% vs 55.9%; P = .008), serrated lesion detection rate (34.6% vs 22.1%; P = .02), and mean number of polyps detected (2.04 vs 1.35; P = .02) were significantly higher in the NBI group than in the LCI group. There was also a trend of higher adenoma detection rate in the NBI group compared with the LCI group (51.5% vs 39.7%, respectively; P = .05). Multivariable analysis confirmed that use of NBI (adjusted odds ratio, 1.99; 95% confidence interval, 1.09-3.68) and withdrawal time >8 minutes (adjusted odds ratio, 5.11; 95% confidence interval, 2.79-9.67) were associated with polyp detection. Overall, 20.5% of polyps and 18.1% of adenomas were missed by the first colonoscopy, but there was no significant difference in the miss rates between the 2 groups. CONCLUSION: NBI was significantly better than LCI for colorectal polyp detection. However, both LCI and NBI missed 20.5% of polyps. (Clinical trial registration number: NCT03336359.).
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Adenoma/diagnóstico por imagen , Neoplasias del Colon/diagnóstico por imagen , Pólipos del Colon/diagnóstico por imagen , Colonoscopía , Aumento de la Imagen , Imagen de Banda Estrecha , Adenoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios ProspectivosRESUMEN
BACKGROUND: Viral hepatitis epidemiological data are important for the World Health Organization plan of eliminating viral hepatitis. We aimed to document the prevalence of viral hepatitis A to E in Hong Kong. METHODS: This community-based study was open to all Hong Kong Chinese citizens aged ≥18 years. Baseline data and risk factors were collected. Hepatitis A-E serology was measured, including hepatitis B e antigen, antibodies to hepatitis B e antigen, antibodies to hepatitis D, hepatitis B virus (HBV) DNA for hepatitis B surface antigen (HBsAg)-positive participants, and antibodies to hepatitis B surface antigen and antibodies to hepatitis B core antigen (anti-HBc) in HBsAg-negative participants. Hepatitis C virus (HCV) RNA and genotypes were determined in anti-HCV-positive participants. RESULTS: A total of 10 256 participants were recruited from February 2015 to July 2016. Overall HBsAg seroprevalence was 7.8% (95% confidence interval [CI], 7.3%-8.3%), which was reduced significantly with HBV vaccination (odds ratio, 0.15 [95% CI, .11-.21]). Among HBsAg-negative participants, anti-HBc seroprevalence increased from 5.4% (<26 years) to 60.1% (>65 years). No hepatitis D virus (HDV) cases were detected. Anti-HCV positivity was 0.5% (95% CI, .3%-.6%). Prevalence of antibodies to hepatitis A virus (anti-HAV) and hepatitis E virus (anti-HEV) was 65.2% (95% CI, 64.2%-66.1%) and 33.3% (95% CI, 32.4%-34.2%), respectively, and were influenced by age, family income, and being born in mainland China. CONCLUSIONS: HBV seroprevalence remained high despite universal vaccination. High anti-HBc seroprevalence underlines the potential issue of HBV reactivation during profound immunosuppression. HCV and HDV remained uncommon. Anti-HAV seroprevalence had decreased whereas anti-HEV seroprevalence had risen.
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Hepatitis Viral Humana/epidemiología , Adulto , Anciano , Femenino , Anticuerpos Antihepatitis/inmunología , Antígenos de la Hepatitis/inmunología , Virus de Hepatitis/inmunología , Hepatitis Viral Humana/inmunología , Hong Kong/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Estudios SeroepidemiológicosRESUMEN
BACKGROUND & AIMS: The interaction between chronic hepatitis B (CHB) and hepatic steatosis is poorly understood. We investigated whether measurement of controlled attenuation parameter (CAP), a non-invasive method to quantify steatosis, can assist in monitoring patients with CHB. METHODS: We performed transient elastography, to measure liver stiffness, and made CAP measurements in 1606 patients with CHB (898 treated with nucleoside analogues, for a median 75.4 months) in Hong Kong, from January 2015 through September 2016. We also collected information on patients' medical history, current treatment, and smoking and alcohol habits, anthropometric measurements. We obtained and analyzed fasting blood samples. Severe liver fibrosis was defined, according to guidelines, as a liver stiffness measurement greater than 9.0 kPa in patients with normal level of alanine aminotransferase (ALT) or greater than 12.0 kPa in patients with a level of ALT 1-5-fold the upper limit of normal. Steatosis was defined as a CAP measurement of 248 dB/m or more, and severe steatosis as a CAP measurement or 280 dB/m more. We performed multivariate analysis to identify factors associated with severe fibrosis. RESULTS: The prevalence of steatosis, severe steatosis, and severe fibrosis in our cohort were 40.8%, 22.6%, and 14.1%, respectively. A higher proportion of patients with severe steatosis had severe fibrosis (21.4% vs 11.9% in the overall cohort; P < .001). In multivariate analysis, severe steatosis was associated with severe fibrosis in treatment-naïve patients (odds ratio, 3.60, 95% CI, 1.21-10.75) and in patients receiving treatment (odds ratios: 1.95 [1.06-3.61] for 3 or more years of treatment, 2.28 [1.13-4.61] for 5 or more years of treatment, and 2.79 [1.17-6.62] for 7 or more years of treatment). With every increase in CAP value of 10 dB/m, the risk of severe fibrosis increased by 15% in treatment-naïve patients and by 7%-8% in patients receiving treatment. CONCLUSIONS: Severe steatosis, determined by CAP measurement, is associated with severe fibrosis in treatment-naïve patients with CHB and in patients receiving treatment. Longitudinal studies are required to investigate if steatosis control, in addition to antiviral treatment, can reduce the burden fibrosis in patients with CHB.
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Hígado Graso/epidemiología , Hígado Graso/patología , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/patología , Cirrosis Hepática/epidemiología , Cirrosis Hepática/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , Diagnóstico por Imagen de Elasticidad , Femenino , Estudios de Seguimiento , Hong Kong/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
BACKGROUND & AIMS: Serologic profiles after hepatitis B surface antigen (HBsAg) seroclearance in chronic hepatitis B (CHB) have not been well-studied. METHODS: We employed a highly sensitive HBsAg (hs-HBsAg) assay (lower detection limit 0.5 mIU/ml), 100 times more sensitive than conventional HBsAg measurements. CHB patients achieving HBsAg seroclearance defined by conventional assays were followed up for serum hs-HBsAg, HBV DNA and antibody to HBsAg (anti-HBs) levels at 0 months, 6-12 months and 3-5 years after HBsAg seroclearance. Factors associated with hs-HBsAg detectability were determined. RESULTS: One hundred and nine patients were recruited; 94 (86.2%) were followed up to years 3-5; and 25 patients (22.9%) were on nucleoside analogue therapy for a median duration of 6.0 (range 1.5-12.7) years before HBsAg seroclearance. Detectable hs-HBsAg was noted in 88 (80.7%), 60 (55.0%) and 20 (21.3%) patients at 0 months, 6-12 months and 3-5 years respectively. At years 3-5, genotype B patients, when compared to genotype C patients, had a higher anti-HBs positive rate (63.2% and 41.1% respectively, P = 0.036). Serum anti-HBs positivity, when compared to persistent anti-HBs negativity, was associated with a lower rate of hs-HBsAg detection (7.4% and 40% respectively, P < 0.001). Multivariate analysis showed anti-HBs negativity at years 3-5 to be independently associated with persistently positive hs-HBsAg (P = 0.007, odds ratio 7.1, 95% confidence interval 1.7-29.3). CONCLUSION: Serum hs-HBsAg could detect HBsAg presence in a substantial proportion of CHB after HBsAg seroclearance defined by conventional assays, especially among anti-HBs negative individuals. Serum hs-HBsAg could potentially assist differentiating HBsAg-negative CHB from individuals with only past HBV exposure without carrier state.
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ADN Viral/sangre , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/sangre , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/uso terapéutico , Femenino , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B , Hepatitis B Crónica/tratamiento farmacológico , Hong Kong , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Carga Viral , Adulto JovenRESUMEN
OBJECTIVE: Treatments with sequential therapy (SEQ) or bismuth quadruple (QUAD) therapy have been proposed as empirical firstline regimens for Helicobacter pylori. We compared the efficacy and tolerability of 10 day SEQ with 10 day modified QUAD as both firstline and secondline treatments for H pylori in a randomised crossover study. DESIGN: H pylori positive and treatment naïve patients were randomly assigned to receive either 10 day SEQ (esomeprazole for 10â days, amoxicillin for an initial 5â days, followed by clarithromycin and metronidazole for a subsequent 5â days) or modified QUAD (esomeprazole, bismuth subcitrate, tetracycline and metronidazole). H pylori eradication was confirmed by urea breath test at 8â weeks. Patients who failed the initial assigned treatment were crossed over to receive the alternate regimen. The primary outcome was eradication rates of firstline treatment by intention to treat (ITT) and per protocol (PP) analyses. RESULTS: 357 patients were randomised to receive either SEQ or QUAD. The PP eradication rates of the SEQ and QUAD groups were 95.2% and 98.8%, respectively (p=0.10). Based on ITT analysis, the corresponding eradication rates were 89.4% and 92.7%, respectively (p=0.36). Eight (4.8%) patients in the SEQ and two (1.2%) patients in the QUAD who failed the firstline treatment were crossed over to the alternate regimen with 100% retreatment success. The overall incidence of adverse events was higher in the QUAD (16.7%) than in the SEQ (8.1%; p=0.032) group. CONCLUSIONS: Ten day sequential and modified bismuth quadruple therapies are both highly effective as empirical firstline therapies for H pylori in Chinese patients. CLINICALTRIALSGOV: NCT 01760824.
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Antiácidos/uso terapéutico , Antibacterianos/uso terapéutico , Antiulcerosos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Compuestos Organometálicos/uso terapéutico , Adulto , Anciano , Amoxicilina/uso terapéutico , Pueblo Asiatico , Pruebas Respiratorias , China , Claritromicina/uso terapéutico , Estudios Cruzados , Esquema de Medicación , Quimioterapia Combinada , Esomeprazol/uso terapéutico , Femenino , Estudios de Seguimiento , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/etnología , Humanos , Análisis de Intención de Tratar , Masculino , Metronidazol/uso terapéutico , Persona de Mediana Edad , Estudios Prospectivos , Tetraciclina/uso terapéutico , Resultado del TratamientoRESUMEN
OBJECTIVES: The benefits of narrow band imaging (NBI) on enhancing colorectal adenoma detection remain questionable. We tested whether the new generation of NBI (190-NBI), which is twice as bright as the previous version, would improve adenoma detection when compared with high-definition white light (HD-WL) colonoscopy. METHODS: It was a randomized controlled trial with tandem colonoscopy. We recruited patients who underwent colonoscopy for symptoms, screening, or surveillance. Patients were randomized for the use of either 190-NBI or HD-WL on withdrawal. Tandem colonoscopy was performed by using the same assigned colonoscope and withdrawal method. Lesions detected on first-pass and second-pass examination were used for adenoma detection and miss rates, respectively. The primary outcomes were adenoma and polyp detection rates. RESULTS: A total of 360 patients were randomized to undergo either 190-NBI or HD-WL colonoscopy. Both the adenoma and polyp detection rates were significantly higher in the 190-NBI group compared with the HD-WL group (adenoma: 48.3% vs. 34.4%, P=0.01; polyps: 61.1% vs. 48.3%, P=0.02). The mean number of polyps detected per patient was higher in the 190-NBI group (1.49% vs. 1.13, P=0.07). There was no significant difference in the adenoma miss rates between the two groups (21.8% vs. 21.2%). Multivariate analysis showed that the use of 190-NBI (odds ratio (OR) 1.85; 95% confidence interval (CI) 1.10-3.12), withdrawal time (OR 1.29; CI 1.19-1.38), patient's age (OR 1.04; CI 1.01-1.06), and male gender (OR 2.38; CI 1.42-3.99) were associated with adenoma detection. CONCLUSIONS: 190-NBI colonoscopy was superior to the conventional HD-WL in detecting colorectal adenomas or polyps, but there was no significant difference in adenoma miss rates.
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Adenoma/diagnóstico , Pólipos del Colon/diagnóstico , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Imagen de Banda Estrecha/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Much of our understanding of bacterial behavior stems from studies in liquid culture. In nature, however, bacteria frequently live in densely packed spatially-structured communities. How does spatial structure affect bacterial cooperative behaviors? In this work, we examine rhamnolipid production-a cooperative and virulent behavior of Pseudomonas aeruginosa. Here we show that, in striking contrast to well-mixed liquid culture, rhamnolipid gene expression in spatially-structured colonies is strongly associated with colony specific growth rate, and is impacted by perturbation with diffusible quorum signals. To interpret these findings, we construct a data-driven statistical inference model which captures a length-scale of bacterial interaction that develops over time. Finally, we find that perturbation of P. aeruginosa swarms with quorum signals preserves the cooperating genotype in competition, rather than creating opportunities for cheaters. Overall, our data demonstrate that the complex response to spatial localization is key to preserving bacterial cooperative behaviors.
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Interacciones Microbianas/fisiología , Modelos Biológicos , Proteínas Bacterianas/genética , Biomasa , Recuento de Colonia Microbiana , Regulación Bacteriana de la Expresión Génica , Glucolípidos/genética , Glucolípidos/metabolismo , Locomoción , Interacciones Microbianas/genética , Mutación , Imagen Óptica , Regiones Promotoras Genéticas , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiología , Percepción de Quorum , Análisis Espacio-TemporalRESUMEN
BACKGROUND/AIMS: Data on treatment efficacy and safety of glecaprevir/pibrentasvir (GLE/PIB) for chronic hepatitis C virus (HCV) infection in Asian patients with severe renal impairment are limited. This study aimed to study the treatment and side effects of GLE/PIB in these patients infected with non-1 genotype (GT) HCV. METHODS: We prospectively recruited patients with Child's A cirrhosis and eGFR <30 mL/min/1.73 m2 in Hong Kong and Taiwan during 2017-2018 to receive GLE/PIB treatment. RESULTS: Twenty-one patients (GT2, n=7; GT3, n=6; and GT6, n=8) received GLE/PIB for 11.2±1.8 weeks. All except one were treatment-naïve. GLE/PIB was initiated in 16 patients while on dialysis (seven on peritoneal dialysis [PD] and nine on hemodialysis) and in five patients before dialysis. One patient died of PD-related peritonitis during treatment and two were lost to follow up. The SVR12 rate in the remaining 18 patients was 100%. All patients achieved undetectable levels at 4-, 12-, 24- and 48-week after treatment. Patients with deranged alanine aminotransferase showed normalization after 4 weeks and the response was sustained for 48 weeks. No significant adverse event was observed. CONCLUSION: GLE/PIB treatment was associated with high efficacy and tolerability in HCV-infected patients with severe renal impairment.
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Hepatitis C Crónica/tratamiento farmacológico , Insuficiencia Renal/tratamiento farmacológico , Ácidos Aminoisobutíricos , Antivirales/uso terapéutico , Bencimidazoles , Niño , Ciclopropanos , Femenino , Hepacivirus , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Masculino , Prolina/análogos & derivados , Pirrolidinas , Quinoxalinas , SulfonamidasRESUMEN
BACKGROUND: Influenza causes excessive hospitalizations and deaths. The study assessed the efficacy and safety of a clarithromycin-naproxen-oseltamivir combination for treatment of serious influenza. METHODS: From February to April 2015, we conducted a prospective open-label, randomized, controlled trial. Adult patients hospitalized for A(H3N2) influenza were randomly assigned to a 2-day combination of clarithromycin 500 mg, naproxen 200 mg, and oseltamivir 75 mg twice daily, followed by 3 days of oseltamivir or to oseltamivir 75 mg twice daily without placebo for 5 days as a control method (1:1). The primary end point was 30-day mortality. The secondary end points were 90-day mortality, serial nasopharyngeal aspirate (NPA) virus titer, percentage of neuraminidase-inhibitor-resistant A(H3N2) virus (NIRV) quasispecies, pneumonia severity index (PSI), and duration of hospital stay. RESULTS: Among the 217 patients with influenza A(H3N2) enrolled, 107 were randomly assigned to the combination treatment. The median age was 80 years, and 53.5% were men. Adverse events were uncommon. Ten patients died during the 30-day follow-up. The combination treatment was associated with lower 30-day mortality (P = .01), less frequent high dependency unit admission (P = .009), and shorter hospital stay (P < .0001). The virus titer and PSI (days 1-3; P < .01) and the NPA specimens with NIRV quasispecies ≥ 5% (days 1-2; P < .01) were significantly lower in the combination treatment group. Multivariate analysis showed that combination treatment was the only independent factor associated with lower 30-day mortality (OR, 0.06; 95% CI, 0.004-0.94; P = .04). CONCLUSIONS: Combination treatment reduced both 30- and 90-day mortality and length of hospital stay. Further study of the antiviral and immunomodulatory effects of this combination treatment of severe influenza is warranted. TRIAL REGISTRY: BioMed Central; No.: ISRCTN11273879 DOI 10.1186/ISRCTN11273879; URL: www.isrctn.com/ISRCTN11273879.
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Antibacterianos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Antivirales/uso terapéutico , Claritromicina/uso terapéutico , Gripe Humana/tratamiento farmacológico , Naproxeno/uso terapéutico , Oseltamivir/uso terapéutico , Anciano , Anciano de 80 o más Años , Farmacorresistencia Viral , Quimioterapia Combinada , Femenino , Hospitalización , Humanos , Subtipo H3N2 del Virus de la Influenza A , Gripe Humana/inmunología , Tiempo de Internación , Masculino , Mortalidad , Nasofaringe/virología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Carga ViralRESUMEN
We previously reported that proper dilution of sera that contain IgG monoclonal proteins (M-proteins) is necessary for accurate quantitation of serum albumin and M-protein concentrations separated by serum protein electrophoresis (SPE) using the Beckman PARAGON agarose electrophoresis system. We now report the significance of pre-electrophoretic serum dilution for M-protein quantitation of sera from patients with IgA and IgM monoclonal gammopathy. We measured M-proteins by SPE in 82 serum samples from 29 patients with IgA and 72 samples from 23 patients with IgM monodonal gammopathy. The serum M-protein concentrations (mean +/- SD) at 1:5, 1:10, and 1:20 dilutions (v/v) for all samples of both types were 49.7 +/- 12.9, 49.1 +/- 13.1, and 47.8 +/- 13.0 g/L, respectively. Thirty-two (20.8%) of 154 sera showed varying degrees of increase in M-protein concentrations with serum dilutions higher than 1:5; only 8 (5.2%) showed an increase 3 SDs. By SPE, the M-protein concentration (mean +/- SD) of these 8 sera at 1:5, 1:10, and 1:20 dilutions were 52.6 +/- 7.8, 57.1 +/- 7.2, and 57.6 +/- 7.1 g/L, respectively; the albumin concentrations (mean +/- SD) were 41.4 +/- 4.4, 37.9 +/- 3.8, and 37.1 +/- 2.9 g/L, respectively. The corresponding albumin concentration (mean +/- SD) was 36.8 +/- 3.7 g/L, assayed by the bromcresol green dye-binding method. These 8 samples were obtained from 3 patients, 2 with IgM kappa and 1 with IgA lambda monoclonal gammopathy. On the electrophoresis membranes, the M-protein bands of these 8 samples were narrow, thin, and dense; upon scanning, they appeared taller and thinner than the corresponding albumin bands. The samples of this subset contained relatively high concentrations of M-protein and total serum protein. We conclude that a pre-electrophoretic dilution of 1:5 (v/v) is adequate for most sera with IgA or IgM M-proteins. However, 1:10 or 1:20 dilution is occasionally required for a subset of sera with IgA or IgM M-proteins that show an unusually thin, narrow, and dense M-protein band and have high total serum protein content.