[Show abstract][Hide abstract] ABSTRACT: 1. Extended-spectrum beta-lactamase(ESBL) resistance in Enterobacter spp may be under-recognised. 2. Detection methods for ESBL resistance in Enterobacter spp may need to be modified.
Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine 12/2009; 15 Suppl 9:4-5.
[Show abstract][Hide abstract] ABSTRACT: Bronchiectasis is a common disease in the Asia-Pacific and affected patients suffer from chronic sputum production and recurrent exacerbations. Bronchiectasis is largely idiopathic although there is diverse aetiology. The pathogenesis of bronchiectasis comprises infective, inflammatory and emzymetic elements. These interact to perpetuate continued airway damage in bronchiectasis leading to progressive airway and lung damages. Treatment of bronchiectasis is unsatisfactory and there are only very few trials. Existing data suggest some efficacy of inhaled corticosteroid therapy, which has been shown recently to clinical and anti-inflammatory properties in bronchiectasis. Immunomodulating agent such as low-dose macrolides have also been shown to have some efficacy although more data are needed to advocate their long-term usage. Antibiotic therapy is complex in bronchiectasis and includes short-term empirical treatment for acute exacerbation, and consideration of long-term maintenance of oral, nebulized and i.v. therapy. This long-neglected illness should receive more research attention in order that we can have better understanding of its aetiology, pathogenesis and treatment.
[Show abstract][Hide abstract] ABSTRACT: Asia is a highly heterogeneous region with vastly different cultures, social constitutions and populations affected by a wide spectrum of respiratory diseases caused by tropical pathogens. Asian patients with community-acquired pneumonia differ from their Western counterparts in microbiological aetiology, in particular the prominence of Gram-negative organisms, Mycobacterium tuberculosis, Burkholderia pseudomallei and Staphylococcus aureus. In addition, the differences in socioeconomic and health-care infrastructures limit the usefulness of Western management guidelines for pneumonia in Asia. The importance of emerging infectious diseases such as severe acute respiratory syndrome and avian influenza infection remain as close concerns for practising respirologists in Asia. Specific infections such as melioidosis, dengue haemorrhagic fever, scrub typhus, leptospirosis, salmonellosis, penicilliosis marneffei, malaria, amoebiasis, paragonimiasis, strongyloidiasis, gnathostomiasis, trinchinellosis, schistosomiasis and echinococcosis occur commonly in Asia and manifest with a prominent respiratory component. Pulmonary eosinophilia, endemic in parts of Asia, could occur with a wide range of tropical infections. Tropical eosinophilia is believed to be a hyper-sensitivity reaction to degenerating microfilariae trapped in the lungs. This article attempts to address the key respiratory issues in these respiratory infections unique to Asia and highlight the important diagnostic and management issues faced by practising respirologists.
[Show abstract][Hide abstract] ABSTRACT: The burden of lung disease in Hong Kong is not known. This study determined the mortality and hospitalization rates of respiratory diseases in Hong Kong in 2005, their trend in the past decade and their incidence/prevalence.
Mortality data were obtained from the Department of Health and hospitalization data from the Hospital Authority, Hong Kong. Incidence/prevalence data were obtained from local registries or local studies. Trends of mortality and hospitalization rates of various respiratory diseases from 1997 and 2005 were calculated after age standardization and were tested for significance using negative binomial regression analysis. Age standardized mortality rates in Hong Kong were compared with those of the UK and globally.
Respiratory disease was the most common cause of mortality and hospitalization in Hong Kong in 2005. Globally and in the UK, cardiovascular disease ranked first in mortality. Respiratory infections ranked first in respiratory mortality, followed by respiratory tract cancer and chronic obstructive lung disease. Respiratory infections also ranked first followed by chronic obstructive lung disease in the utilization of respiratory inpatient bed-days. While mortality rates from all respiratory diseases decreased in the past decade, hospitalization rates remained unchanged. Unlike other respiratory diseases, mortality from respiratory infections have increased since 2001. Smoking is the most important risk factor in non-communicable respiratory diseases.
Respiratory disease is responsible for the highest health-care burden locally. Increased efforts in improving management and prevention of these diseases, including tobacco control, improving air quality and vaccination against influenza and pneumococci, are necessary.
[Show abstract][Hide abstract] ABSTRACT: This study evaluated the antimicrobial resistance profile of outpatient urinary Escherichia coli isolated from women obtained throughout Hong Kong during 2004-2005. Of 1067 single patient isolates analyzed, 60.1% were resistant to ampicillin, 34% were resistant to co-trimoxazole, and 22.1% were resistant to ciprofloxacin. Thirty-four (6.6%) of 519 isolates in 2004 and 55 (10%) of 548 isolates in 2005 were extended-spectrum beta-lactamase (ESBL) producers with a CTX-M phenotype. Rates of non-beta-lactam resistance and ESBL production were strongly influenced by patient age. The age-stratified rates for dual co-trimoxazole and ciprofloxacin resistance and for ESBL production were 10.9% and 7.6% in women aged 18-35 years, 13% and 6.9% in women aged 36-50 years, 20.4% and 8.8% in women aged 51-64 years, and 23.7% and 11.8% in women aged > or =65 years, respectively. Nitrofurantoin and fosfomycin remain active against >90% of the isolates, irrespective of the resistance phenotypes for other drugs. Our results documented the emergence of problematic resistance phenotypes among community urinary E. coli and highlight the need to explore strategies for their containment.
[Show abstract][Hide abstract] ABSTRACT: To conduct a territory-wide study of extended-spectrum beta-lactamases (ESBLs) among community isolates of urinary Escherichia coli from women in Hong Kong.
Up to 50 consecutive single-patient E. coli isolates, collected from 13 laboratories in 2004, were studied. The ESBLs were characterized by PCR sequencing using specific primers. The epidemiological relationship of the isolates was studied by PFGE and phylogenetic group PCRs.
Forty-two ESBL producers were found among 600 consecutive isolates tested. The ESBL prevalence was 7.3% (15/205) for women aged 18-35 years, 5% (11/219) for women aged 36-50 years, 6.3% (4/63) for women aged 51-64 years and 10.6% (12/113) for women aged >or=65 years (P=0.3). The ESBL-producing isolates were often multidrug-resistant and CTX-M-14 was found in 37 isolates, CTX-M-15 in 3 isolates and CTX-M-3 in 2 isolates. PFGE revealed no significant clusters among the ESBL producers. Overall, CTX-M-14 producers were significantly more likely to belong to group D than non-ESBL producers [18/37 (48.6%) versus 13/57 (22.8%), P=0.009]. However, 7 of 13 (53.8%) CTX-M-14 producers from women aged 18-35 years represented phylogenetic group B2, compared with 7 of 24 (29.2%) for women of all other ages (P=0.1).
The study documented the community emergence of CTX-M as the predominant ESBL type among urinary isolates from women. The spread of CTX-M enzymes among isolates from young women is concerning and deserves close monitoring.
Journal of Antimicrobial Chemotherapy 07/2007; 60(1):140-4. · 5.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To assess the immediate and sustained psychological health of health care workers who were at high risk of exposure during the severe acute respiratory syndrome (SARS) outbreak.
At the peak of the 2003 SARS outbreak, we assessed health care workers in 2 acute care Hong Kong general hospitals with the Perceived Stress Scale (PSS-10). One year later, we reassessed these health care workers with the PSS-10, the 21-Item Depression and Anxiety Scale (DASS-21), and the Impact of Events Scale-Revised (IES-R). We recruited high-risk health care workers who practised respiratory medicine and compared them with nonrespiratory medicine workers, who formed the low-risk health care worker control group.
In 2003, high-risk health care workers had elevated stress levels (PSS-10 score = 17.0) that were not significantly different from levels in low-risk health care worker control subjects (PSS-10 score = 15.9). More high-risk health care workers reported fatigue, poor sleep, worry about health, and fear of social contact, despite their confidence in infection-control measures. By 2004, however, stress levels in the high-risk group were not only higher (PSS-10 score = 18.6) but also significantly higher than scores among low-risk health care worker control subjects (PSS-10 score = 14.8, P < 0.05). In 2004, the perceived stress levels in the high-risk group were associated with higher depression, anxiety, and posttraumatic stress scores (P < 0.001). Posttraumatic stress scores were a partial mediator of the relation between the high risk of exposure to SARS and higher perceived stress.
Health care workers who were at high risk of contracting SARS appear not only to have chronic stress but also higher levels of depression and anxiety. Front-line staff could benefit from stress management as part of preparation for future outbreaks.
Canadian journal of psychiatry. Revue canadienne de psychiatrie 04/2007; 52(4):241-7. · 2.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Our study examined the stress level and psychological distress of severe acute respiratory syndrome (SARS) survivors 1 year after the outbreak.
During the SARS outbreak in 2003, we used the 10-item Perceived Stress Scale (PSS-10) to assess SARS survivors treated in 2 major hospitals (non-health care workers, n = 49; health care workers, n = 30). We invited SARS survivors from the same hospitals (non-health care workers, n = 63; health care workers, n = 33) to complete the PSS-10 again in 2004. At that time, they were also asked to complete the General Health Questionnaire (GHQ-12) and measures of depression, anxiety, and posttraumatic symptoms. PSS-10 scores were also obtained from matched community control subjects during the outbreak (n = 145) and again in 2004 (n = 112).
SARS survivors had higher stress levels during the outbreak, compared with control subjects (PSS-10 scores = 19.8 and 17.9, respectively; P < 0.01), and this persisted 1 year later (PSS-10 scores = 19.9 and 17.3, respectively; P < 0.01) without signs of decrease. In 2004, SARS survivors also showed worrying levels of depression, anxiety, and posttraumatic symptoms. An alarming proportion (64%) scored above the GHQ-12 cut-off that suggests psychiatric morbidity. During the outbreak, health care worker SARS survivors had stress levels similar to those of non-health care workers, but health care workers showed significantly higher stress levels in 2004 (PSS-10 score = 22.8, compared with PSS-10 score = 18.4; P < 0.05) and had higher depression, anxiety, posttraumatic symptoms, and GHQ-12 scores.
One year after the outbreak, SARS survivors still had elevated stress levels and worrying levels of psychological distress. The situation of health care worker SARS survivors is particularly worrying. The long-term psychological implications of infectious diseases should not be ignored. Mental health services could play an important role in rehabilitation.
Canadian journal of psychiatry. Revue canadienne de psychiatrie 04/2007; 52(4):233-40. · 2.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In this study, the authors examined perceived benefits and costs of the outbreak of severe acute respiratory syndrome (SARS). Mixed accounts of benefits and costs, rather than exclusive accounts of only benefits or costs, were proposed to be characterized by nondefensiveness and enduring changes in psychosocial resources. Participants were 70 SARS recoverers, 59 family members of SARS recoverers, and 172 healthy adults residing in Hong Kong--a SARS-affected region. Results show that participants giving an exclusive account of benefits had higher levels of defensiveness than those giving a mixed account and those giving an exclusive account of costs. Only the perceived impact of benefits given in mixed accounts were related to future accruements in personal and social resources over an 18-month period.
Journal of Consulting and Clinical Psychology 11/2006; 74(5):870-9. · 4.85 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Airway epithelial cells are the first targets of environmental stimuli and local cytokines. Pyocyanin-induced synergism with interleukin (IL)-1 or tumour necrosis factor (TNF) in triggering IL-8 release has been documented previously. In this study, IL-8 mRNA and protein expression were examined in cultured human bronchial epithelial cells (BEAS-2B) stimulated with pyocyanin alone, and in combination with IL-1beta or phorbol 12,13-dibutyrate (PDBu) in the absence and presence of a group of glucocorticoids. IL-8 mRNA was measured by RT-PCR, and IL-8 protein by ELISA (cell supernatants). Pyocyanin alone produced no increase in IL-8 mRNA and release. However, pyocyanin upregulated the stimulatory effect of IL-1beta or PDBu on the release of IL-8 in a dose-dependent manner. The stimulatory effect of pyocyanin on the IL-1beta- or PDBu-stimulated IL-8 release was reduced in the presence of dexamethasone, budesonide, and fluticasone. Budesonide and fluticasone were 10-fold more potent than dexamethasone. The protein kinase C (PKC) inhibitor, Go6976, also significantly reduced the stimulatory effect of pyocyanin on IL-1beta, and PDBu increased IL-8 release. In conclusion, this study shows that PKC signal pathway seems to be involved in the pyocyanin-mediated upregulation of the IL-1beta and PDBu-induced IL-8 release in BEAS-2B cells. These findings suggest that a vicious cycle perpetuating inflammation may exist in the biologic milieu of bronchiectatic patients infected with Pseudomonas aeruginosa due to the production of pyocyanin. The priming action of pyocyanin appears to be blocked by glucocorticoids, thus providing in vitro data in support of the clinical efficacy of inhaled glucocorticoids as anti-inflammatory drugs.
Respiratory Medicine 10/2006; 100(9):1614-22. · 2.92 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Antioxidants play an important role in counteracting the effects of potential carcinogens. We investigated the risk of lung cancer development with respect to manganese superoxide dismutase (MnSOD) and catalase genetic polymorphisms and their association with erythrocyte antioxidant activities.
This was a case-control study involving patients with confirmed lung cancer and age-matched healthy controls. Genotyping of MnSOD and catalase in DNA extracted from peripheral white cells was performed by polymerase chain reaction-based restriction fragment length polymorphism. Erythrocyte superoxide dismutase and catalase activities were measured spectrophotometrically using chemical kinetic reactions.
We recruited 240 patients with lung cancer (63% male, aged 55.6 +/- 11.9 years, 58% adenocarcinoma, 85% clinical stage III or IV) and 240 age-matched healthy controls. The frequencies of the Val allele of MnSOD gene and the C allele of catalase gene were common (>86% and 90%, respectively), with similar distribution, in both patients with lung cancer and controls. The homozygous variant genotypes of MnSOD and catalase were not associated with increased lung cancer risk. The erythrocyte SOD and catalase activity was significantly lower among all patients with lung cancer as a whole compared with controls, irrespective of genotypes. However, patients with adenocarcinoma and non-adenocarcinoma showed differences in SOD and catalase activity among different genotypes in comparison with controls.
The common Val16Ala MnSOD polymorphism and C-T substitution in the promoter region of the catalase gene do not confer increased or reduced risk of lung cancer in Chinese in Hong Kong.
Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 09/2006; 1(7):648-53. · 4.55 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In a retrospective study designed to gather information in a region with high antimicrobial resistance, the outcomes of 216 episodes of laboratory-confirmed pneumococcal bacteremia treated in Hong Kong between 1995 and 2001 were assessed. The patients had a mean age (+/-standard deviation) of 40+/-33.7 years. In all patients, the clinical diagnosis was confirmed by isolation of Streptococcus pneumoniae from blood (n=216), cerebrospinal fluid (n=7) and/or other sterile sites (n=12). Penicillin nonsusceptibility was found in 37.5% of the isolates (20.8% intermediate and 16.7% resistant). Penicillin nonsusceptibility was not a risk factor for inpatient mortality (p=0.7), nor did it affect duration of fever (p=0.4), requirement for intensive care unit admission (p=0.4) or development of suppurative complications (p=0.2). Advanced age (OR 11.3, 95%CI 4.5-28.2, p<0.01), critical illness (OR 11.3, 95%CI 4.5-28.2, p<0.001) and discordant therapy (OR 4.3, 95%CI 1.7-10.9, p<0.002) involving agents with poor anti-pneumococcal activity (but not penicillins and broad-spectrum beta-lactam agents) were significantly associated with mortality.
European Journal of Clinical Microbiology 05/2006; 25(5):323-7. · 2.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Bronchiectasis is a chronic inflammatory and infective airway disease characterized by irreversible dilatation of the bronchi and persistent purulent sputum. Transforming growth factor-beta(1) (TGF-beta(1)) has been found to be increased in the lungs or bronchoalveolar lavage fluid of patients with inflammatory lung diseases. However, little is known on the serum TGF-beta(1) levels in patients with bronchiectasis. We aimed to determine the serum TGF-beta(1) concentrations in 95 patients with stable bronchiectasis (63 women; mean+/-sd age, 58.9+/-14.1 years) and 68 control subjects (23 women; 48.9+/-12.8 years) by ELISA, and to correlate with clinical parameters. The serum TGF-beta(1) levels were significantly higher in bronchiectatic patients compared with control subjects (median [range], 1812.5 pg/ml [1226.4-4114.5 pg/ml] vs. 1342.4 pg/ml [940.3-2371.7 pg/ml]; P<0.001). There was, however, no correlation between serum TGF-beta(1) levels with FEV(1) (% predicted), FVC (% predicted), 24h sputum volume, the number of bronchiectatic lung lobes or total white blood cell count (P>0.05). Our findings support previous indications that TGF-beta(1) may contribute to bronchiectatic airway inflammation. Further studies on the potential mechanisms and pathogenesis implications of this elevation should also be pursued in future.
Respiratory Medicine 11/2005; 99(10):1223-8. · 2.92 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A study was conducted to evaluate the occurrence and characterization of extended-spectrum beta-lactamases (ESBLs) among blood isolates of Proteus mirabilis collected over a 4 year period in Hong Kong.
Production of ESBLs among 99 consecutive and non-duplicate isolates was evaluated by the double-disc synergy test. The ESBLs were characterized by isoelectric focusing and PCR sequencing using specific primers. The epidemiological relationship of the isolates was studied by the Dienes test and PFGE.
ESBLs were identified in 13 isolates, from none in 1999-2000 and up to 18.5% (5/27) in 2001 and 25.8% (8/31) in 2002. The ESBL-producing isolates were more resistant to ceftriaxone than to ceftazidime, and were more likely than non-ESBL-producers to have resistance to ciprofloxacin (76.9% versus 14%) and gentamicin (38.5% versus 9.3%). The ESBL content included CTX-M-13 (n=8), CTX-M-14 (n=3), SHV-5 (n=2), TEM-11 (n=1), and an unidentified ESBL with a pI of 7.5. The Dienes test revealed that the genetic background in the 99 isolates was highly heterogeneous, with 54 distinct types among 92 isolates and seven were non-typeable. Among the 13 ESBL-producing isolates, five different backgrounds, including one cluster (Dienes-pulsotype A) with nine isolates, were identified by both Dienes test and PFGE, thus suggesting both clonal and multi-clonal spread of the CTX-M enzymes.
Our findings indicate the emergence of CTX-M enzymes among P. mirabilis in Hong Kong. More ESBL screening of this species is required to improve their recognition.
Journal of Antimicrobial Chemotherapy 07/2005; 55(6):840-5. · 5.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: It has been suggested that patients with bronchiectasis might have increased central microtubular orientation angle (CMOA), which leads to poor coordination of ciliary beating, and consequently impairment of airway defence. We have employed transmission electron microscopy to assess CMOA of ciliated nasal mucosa in a cohort of 133 (81F, 56.8+/-16.1yr) stable bronchiectasis and 59 healthy subjects (30F, 49.3+/-22.1yr). There was no significant difference in CMOA between bronchiectasis (13.2 degree) and control subjects (13.0 degree, P=0.82). There was no significant difference in CMOA among patients according to the etiology of bronchiectasis, presence of nasal symptoms, or sputum status of Pseudomonas aeruginosa infection. Patients with more severe bronchiectasis, i.e. those with FEV(1) <60%, FVC <60%, or more than 4 bronchiectatic lung lobes, had significantly lower CMOA than their counterparts (P<0.05). There was no correlation between CMOA with age, 24h sputum volume, exacerbation frequency, FEV(1), FVC, or the number of bronchiectatic lung lobes (P>0.05). CMOA correlated with ciliary beat frequency (negative), and the percent of cilia showing ultrastructural or microtubular defects (P<0.05). Central microtubular orientation angle does not correlate with clinically important parameters, in contrary to the results reported by previously published smaller scale studies.
Respiratory Medicine 04/2005; 99(3):290-7. · 2.92 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A total of 139 consecutive and non-duplicate bloodstream isolates of Enterobacter spp. collected from inpatients in Hong Kong during 2000-2002 were studied for production of extended-spectrum beta-lactamases (ESBLs).
All isolates were evaluated by the modified double-disc synergy test (m-DDST), the combined disc method (CDM) and the three-dimensional (3D) test. The m-DDST and CDM were modified by the use of cefepime discs. beta-Lactamases were characterized by isoelectric focusing and PCR sequencing using specific primers.
ESBLs were identified in nine isolates (overall 6.5%), including seven of 39 (17.9%) Enterobacter hormaechei, one of 27 (3.7%) Enterobacter aerogenes and the only Enterobacter intermedius strain. The E. intermedius strain was positive only in the 3D test but not in the other two tests. The other eight strains were positive in all three tests. No ESBL was detected in the other species, including non-hormaechei members of the Enterobacter cloacae complex (n=61), Enterobacter agglomerans (n=7), Enterobacter gergoviae (n=4) and Enterobacter sakazakii (n=1). The ESBL content included five different CTX-M enzymes (CTX-M-9, CTX-M-13, CTX-M-14, CTX-M-24 and a novel CTX-M-2-like beta-lactamase), SHV-12 (n=2) and unidentifiable ESBLs with a pI of 7.7 or 7.9 in two strains. The seven ESBL-producing E. hormaechei were genotyped by pulsed-field gel electrophoresis and were found to be unrelated to each other. In three of the CTX-M-producing strains, ISEcp1-like elements, including promoters for the beta-lactamase gene, were found.
Our data underscore the diversity of CTX-M enzymes among Enterobacter spp. in Hong Kong.
Journal of Antimicrobial Chemotherapy 04/2005; 55(3):326-32. · 5.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Although ciliary dysfunction and numerous ultrastructural defects have been described, and these could be etiologically important in the development of bronchiectasis, their correlation with relevant clinical parameters have not been systematically evaluated. We have prospectively evaluated the prevalence and clinical significance of ciliary beat frequency and ultrastructural defects of nasal respiratory mucosa obtained from 152 stable patients with idiopathic bronchiectasis (100F, 57.7 +/- 15.2 yrs) and 127 control subjects (58F, 56.0 +/- 24.2 yrs). Bronchiectasis patients had significantly slower ciliary beat frequency (p < 0.05), and a greater percent of patients had central and peripheral microtubular defects (OR 14.4, 95% CI 5.6-36.8), namely, extra peripheral microtubules, "9 + 1", "8 + 2", and compound cilia (p < 0.05), but not microtubular disarrangement, extra matrix or ciliary tail abnormalities (p > 0.05), than controls. Bronchiectasis patients also had a greater proportion of cilia with any ultrastructural microtubular defects, compound cilia, and ciliary tails than controls (p < 0.05). Ciliary beat frequency did not correlate with clinically relevant parameters (p > 0.05). However, the percent of cilia with central, but not peripheral, microtubular defects correlated with 24 h sputum volume (r = 0.40, p = 0.001, and r = -0.04, p = 0.70, respectively) and FEV1 (r = -0.24, p = 0.01, and r = 0.00, p = 0.99 respectively). Our results strongly suggest a pathogenic role for central microtubular defects in the development of idiopathic bronchiectasis.
Beiträge zur Klinik der Tuberkulose 03/2005; 183(2):73-86. · 2.17 Impact Factor