Ivan F N Hung

Ivan F N Hung
The University of Hong Kong | HKU · Department of Medicine

MBChB (Bristol) MD FRCP

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215
Publications
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Publications

Publications (215)
Article
Objectives We evaluated impact of COVID-19 vaccination on thyroid function and antibodies, and influence of pre-existing thyroid autoimmunity on neutralizing antibody (NAb) responses. Methods Adults without history of COVID-19/thyroid disorders who received COVID-19 vaccination during June–August 2021 were recruited. All received two doses of vacc...
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Background: Both lymphopenia and thyroid dysfunction are commonly observed among COVID-19 patients. Whether thyroid function independently correlates with lymphocyte counts (LYM) remains to be elucidated. Methods: We included consecutive adults without known thyroid disorder admitted to Queen Mary Hospital for COVID-19 from July 2020 to April 2021...
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Background: Mounting evidence has revealed the interrelationship between thyroid and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to explain the thyroid dysfunction and autoimmune thyroid disorders observed after coronavirus disease 2019 (COVID-19). There are limited reports of thyroid dysfunction after SARS-CoV-2 vaccination. Meth...
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Identifying effective drug treatments for COVID-19 is essential to reduce morbidity and mortality. Although a number of existing drugs have been proposed as potential COVID-19 treatments, effective data platforms and algorithms to prioritize drug candidates for evaluation and application of knowledge graph for drug repurposing have not been adequat...
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Objective: SARS-CoV-2-related thyroiditis is increasingly recognized. The role of thyroid autoimmunity and SARS-CoV-2 viral load in SARS-CoV-2-related thyroid dysfunction is unclear. We evaluated the thyroid function of a cohort of COVID-19 patients, in relation to their clinical features, biochemical, immunological and inflammatory markers. Metho...
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Rhinovirus is a common cause of upper and lower respiratory tract infections in adults, especially among the elderly and immunocompromised. Nevertheless, its clinical characteristics and mortality risks have not been well described. A retrospective analysis on a prospective cohort was conducted in a single teaching hospital center over a one-year p...
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Background: Gut dysbiosis may contribute to pain and bloating in patients with functional gastrointestinal disease. Aims: To determine if treatment with rifaximin would improve the symptoms of functional dyspepsia in Chinese patients in a double-blinded, randomised, placebo-controlled trial. Methods: Consecutive subjects with a diagnosis of fu...
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Background: The temporal relationship between nucleoside analogue (NA) therapy for chronic hepatitis B (CHB) and liver cancer development has not been evaluated at a population level. Aim: To investigate the impact of nucleoside analogue prescription on liver cancer incidence in a CHB-prevalent region. Methods: We obtained territory-wide nucle...
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Oncovirus-associated malignancies are potentially preventable diseases with major public health significance. Human polyomaviruses (HPyVs) may be associated with oncogenesis or symptomatic illnesses in immunocompromised patients, but the site of viral shedding of most recently discovered HPyVs remains obscure. Using real-time PCR assay using specif...
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OBJECTIVE To study the association between gastrointestinal colonization of carbapenemase-producing Enterobacteriaceae (CPE) and proton pump inhibitors (PPIs). METHODS We analyzed 31,526 patients with prospective collection of fecal specimens for CPE screening: upon admission (targeted screening) and during hospitalization (opportunistic screening...
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Background: Dabigatran, a non-vitamin K antagonist oral anticoagulant, has been shown to prevent stroke in patients with non-valvular atrial fibrillation. Nonetheless, studies show that 10%–30% of those prescribed dabigatran experience dyspepsia that may eventually lead to discontinuation of therapy and loss of clinical benefit. Aim: To evaluate t...
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Aim: With the rapid increase in the incidence of inflammatory bowel disease (IBD) in Asia, the natural course of these patients during the early phase of disease remains poorly defined. We determined the incidence and characteristics of infection related hospitalization in the first year of patients newly diagnosed with IBD in Hong Kong. Methods:...
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Background: Incidence of inflammatory bowel disease (IBD) is increasing in Asia, but population-based prevalence data are limited. This study examined IBD incidence and prevalence based on results of a territory-wide IBD registry in Hong Kong. Methods: We collected data on 2575 patients with IBD (1541 ulcerative colitis [UC], 983 Crohn's disease...
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In recent years, infections caused by Aspergillus sp. have become an emerging focus of clinical microbiology and infectious disease, as the number of patients infected with Aspergillus sp. has increased markedly. Although chronic pulmonary aspergillosis (CPA) is considered a 'semi-invasive' or 'intermediate' disease, little data are available for t...
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Background: Whether low-dose azathioprine (AZA) is effective in maintaining remission in patients with steroid-dependent ulcerative colitis (UC) remains unclear. We assessed the efficacy and safety of low-dose AZA in a Chinese population with UC. Methods: We identified steroid-dependent UC patients in clinical remission on AZA maintenance therap...
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Early diagnosis of acute community-acquired pneumonia (CAP) is important in patient triage and treatment decisions. To identify biomarkers that distinguish patients with CAP from non-CAP controls, we conducted an untargeted global metabolome analysis for plasma samples from 142 patients with CAP (CAP cases) and 97 without CAP (non-CAP controls). Th...
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To identify potential biomarkers for improving diagnosis of melioidosis, we compared plasma metabolome profiles of melioidosis patients compared to patients with other bacteremia and controls without active infection, using ultra-high-performance liquid chromatography-electrospray ionization-quadruple time-of-flight mass spectrometry. Principal com...
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Background Independent risk factors associated with hepatitis B (HBV)-related hepatocellular carcinoma (HCC) after resection remains unknown. An accurate risk score for HCC recurrence is lacking. Methods We prospectively followed up 200 patients who underwent liver resection for HBV-related HCC for at least 2 years. Demographic, biochemical, tumor...
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Background Long-term outcomes in non-HIV immunocompromised patients with disseminated Mycobacterium avium complex (dMAC) infections are unknown and the need for post-treatment secondary prophylaxis against MAC is uncertain in this setting. The objective of this study was to determine the need of continuing secondary anti-MAC prophylaxis in non-HIV...
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Background: Human rhinovirus (HRV) is frequently detected in patients with respiratory tract infection. However, the full clinical spectrum of HRV infection in critically ill patients is not well characterized. Objective: To evaluate the clinical and virological characteristics of critically ill patients with HRV infection. Study design: HRV-s...
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Gastrointestinal colonization by carbapenem-resistant Acinetobacter baumannii (CRAB) and multidrug-resistant Acinetobacter baumannii (MRAB) provides an important reservoir for clinical infections and hospital outbreaks. We conducted a 7-month study in a 3200-bed healthcare network to investigate the prevalence of gastrointestinal colonization of CR...
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Background: Pretreatment with topical imiquimod, a synthetic agonist of toll-like receptor 7, significantly improved the immunogenicity of influenza vaccination in elderly people. We aimed to clarify its effect in a younger age group. Methods: In this double-blind, randomised controlled trial, we enrolled healthy volunteers aged 18-30 years in e...
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Objectives: Stringent measures have been implemented in Hong Kong to prevent human infections due to avian influenza viruses (AIVs). Here, we report the seroprevalence of AIVs among high risk population. Methods: In this prospective study, blood samples were collected in October and November 2013 and in July 2014 from workers at live poultry mar...
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Background and aims: Data on the natural history of elderly-onset ulcerative colitis (UC) are limited. We aimed to investigate clinical features and outcomes of patients with elderly-onset UC. Methods: Patients with a confirmed diagnosis of UC between 1981 and 2013 from 13 hospitals within a territory-wide Hong Kong IBD Registry were included. C...
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Influenza virus A(H7N9) is associated with a high case fatality rate in humans. Multiple viral factors have been postulated to account for high virulence of the virus. It has been reported that patients with influenza A(H7N9) virus infection have relatively low titers of neutralizing antibody than those with seasonal influenza virus infections. In...
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Aims Gastrointestinal haemorrhage is a common complication of antiplatelet and anticoagulation therapy. The aim of this study is to evaluate the impact of warfarin with different time in therapeutic ranges (TTRs) on the risk of major gastrointestinal haemorrhage in atrial fibrillation (AF) patients compared with aspirin. Methods and results In thi...
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Background Pretreatment with topical imiquimod, a synthetic Toll-like receptor 7 agonist, significantly expedited, augmented, and prolonged the immunogenicity of influenza vaccination in elderly patients. The effect of imiquimod pretreatment in young, healthy people is unknown. Methods In this double-blind, randomised controlled trial, we enrolled...
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Although tuberculosis (TB) is a re-emerging disease that affects developing countries and immunocompromised populations in developed countries, current diagnostic methods are far from optimal. Metabolomics is being increasingly used for studies on infectious diseases. We performed metabolome profiling of plasma samples to identify potential biomark...
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Infections with the fungus Talaromyces (formerly Penicillium) marneffei are rare in patients who do not have AIDS. We report disseminated T. marneffei infection in 4 hematology patients without AIDS who received targeted therapy with monoclonal antibodies against CD20 or kinase inhibitors during the past 2 years. Clinicians should be aware of this...
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Clostridium difficile ribotype 002 with hypersporulating capacity has been increasingly identified in Hong Kong. Proactive infection control measures are important to prevent the establishment of endemicity of C. difficile ribotype 002. A total of 329 patients with healthcare-associated C. difficile infection (CDI) were recruited in our healthcare...
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Intradermal immunization has become a forefront of vaccine improvement, both scientifically and commercially. Newer technologies are being developed to address the need to reduce the dose required for vaccination and to improve the reliability and ease of injection, which have been major hurdles in expanding the number of approved vaccines using th...
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Although previous studies have reported the use of metabolomics for Mycobacterium species differentiation, little is known about the potential of extracellular metabolites of Mycobacterium tuberculosis (MTB) as specific biomarkers. Using an optimized ultrahigh performance liquid chromatography-electrospray ionization-quadruple time of flight-mass s...
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An increasing endemicity of multiple-drug-resistant Acinetobacter baumannii (MRAB) ST457 was noted in Hong Kong. The epidemiology, risk factors, and infection control measures to prevent nosocomial transmission of this epidemic clone were analyzed. A total of 5,058 patients cultured positive with A. baumannii between 1 January 2004 and 30 June 2014...
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Background Prolonged asymptomatic carriage of vancomycin-resistant enterococci (VRE) in the gastrointestinal tract and the lack of effective decolonization regimen perpetuate the endemicity of VRE in the healthcare settings. Case presentation We report a regimen for decolonization of gastrointestinal carriage of VRE by a combination of environment...
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Background Human infection caused by the avian influenza A H7N9 virus has a case-fatality rate of over 30%. Systematic study of the pathogenesis of avian H7N9 isolate and effective therapeutic strategies are needed. Methods BALB/c mice were inoculated intranasally with an H7N9 virus isolated from a chicken in a wet market epidemiologically linked...
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Background: Imiquimod, a synthetic Toll-like receptor 7 agonist enhanced immunogenicity of influenza vaccine in a mouse model. We hypothesized that topical imiquimod before intradermal influenza vaccination (TIV) would produce similar effect in human. Methods: We performed a prospective 1-year follow-up, double-blind, randomized, controlled tria...
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Objective: To compare the immunogenicity and safety between full-dose (15 μg) intramuscular (i.m.) and full-dose (15 μg) intradermal (i.d.) immunization of the trivalent influenza vaccine in nursing home older adults. Design: A single-center, randomized, controlled, open-label, parallel group trial from October 2013 to April 2014. Setting: Nin...
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Background: The 23-valent pneumococcal polysaccharide vaccine is recommended for elders, especially those with chronic conditions. Objective: The aim of this study was to determine if an additional multi-component health education intervention increases the uptake rate of the pneumococcal vaccination among older patients with chronic diseases....
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Background & Aims Hepatitis B surface antigen (HBsAg) seroclearance and seroconversion are regarded as favorable outcomes of chronic hepatitis B (CHB). This study aimed to develop artificial neural networks (ANNs) that could accurately predict HBsAg seroclearance or seroconversion on the basis of available serum variables. Methods Data from 203 un...
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The study describes a proactive infection control approach to prevent nosocomial transmission of vancomycin-resistant enterococci (VRE) and tests if this approach is effective for controlling multiple-drug resistant organisms in a nonendemic setting. In response to the increasing prevalence of VRE in Hong Kong since 2011, we adopted a multifaceted...
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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 randomi...
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Seroprevalence survey is the most practical method for accurately estimating infection attack rate (IAR) in an epidemic such as influenza. These studies typically entail selecting an arbitrary titer threshold for seropositivity (e.g. microneutralization [MN] 1∶40) and assuming the probability of seropositivity given infection (infection-seropositiv...
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Background: Entecavir therapy often reduces hepatitis B virus (HBV) DNA to an undetectable level, but HBV DNA remain detectable in some patients. We investigated whether baseline HBV reverse transcriptase (rt) polymorphism and quasispecies complexity and diversity were associated with treatment response. Methods: Pretreatment HBV DNA levels, HBV...
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Human infections caused by avian influenza virus A(H7N9) re-emerged in late 2013. We reported the first Hong Kong patient without risk factors for severe A(H7N9) disease. Direct sequencing was performed on the endotracheal aspirate collected from a 36-year-old female with history of poultry contact. Bioinformatic analysis was performed to compare t...
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Toll-like receptors (TLRs) of innate immune system are known targets for enhancing vaccine efficacy. We investigated whether imiquimod, a synthetic TLR7 agonist, when combined with influenza vaccine can expedite the immune response against influenza infection. BALB/c mice were immunized with monovalent A(H1N1)pdm09 vaccine combined with imiquimod (...
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Background: Surfactant proteins play a key role in alveolar stability. We examined whether single nucleotide polymorphisms (SNPs) related to the surfactant protein genes are associated with severe influenza. Methods: In the first cohort, 12 SNPs related to surfactant protein genes were compared between Chinese patients with severe and mild pande...
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Hepatitis B surface antigen (HBsAg) kinetics during long-term entecavir therapy has not been well investigated. We described the cumulative serologic, virologic and biochemical outcomes and the occurrence of signature entecavir mutations among 222 Chinese treatment-naïve chronic hepatitis B (CHB) patient receiving entecavir for up to 5 years. The m...
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Influenza infection is common among institutionalized older adults. Many nonrandomized observational studies on influenza vaccination suggested that it could reduce influenza-related hospitalizations and mortality in institutionalized older adults. Criticism regarding the effectiveness of influenza vaccine estimated by nonrandomized observational s...