Clinical trial: exposure to ribavirin predicts EVR and SVR in patients with HCV genotype 1 infection treated with peginterferon alpha-2a plus ribavirin

BACKGROUND

The impact of reduced drug exposure on outcomes in patients with chronic hepatitis C has not been determined in routine clinical practice.

AIM

To examine the impact of exposure to peginterferon alpha-2a and ribavirin on early virological response (EVR) and sustained virological response (SVR) in treatment-naive patients with HCV genotype 1 infection enrolled in a large expanded access programme.

METHODS

Eight hundred and ninety-one patients treated for 48 weeks with an initial ribavirin dose of 800 or 1000/1200 mg/day were evaluated. Ribavirin 1000 mg/day (<75 kg) or 1200 mg/day (>or=75 kg) and peginterferon alpha-2a 180 microg/week were considered optimal. The impact of reduced drug exposure (expressed as a percentage of optimal) on EVR and SVR was evaluated.

RESULTS

Mean ribavirin exposure in week 0-12 was 70% and 96% in patients assigned to ribavirin 800 and 1000/1200 mg/day, respectively. EVR and SVR rates were lower in patients assigned to ribavirin 800 than 1000/1200 mg/day (EVR, 75% vs. 84%, respectively, P < 0.001; SVR, 45% vs. 54%, respectively, P = 0.011). Furthermore, there was a strong correlation between achievement of EVR and SVR and ribavirin dose over the first 12 weeks expressed either as absolute dose or proportion of optimal dose received (P < 0.001 for both).

CONCLUSIONS

Ribavirin exposure to week 12 is significantly associated with EVR and SVR in genotype 1 patients. Maintenance of an optimal ribavirin dose is the most important modifiable factor during combination therapy for chronic hepatitis C.

Central neural activation of hyperdynamic circulation in portal hypertensive rats depends on vagal afferent nerves

BACKGROUND

Hyperdynamic circulation in portal hypertensive rats depends on central neural c-fos gene expression, but how the portal hypertensive signal activates central c-fos expression remains obscure.

AIM

To elucidate the afferent pathway from the gut to the central cardiovascular regulatory nuclei in portal hypertensive rats.

METHODS

Cervical vagus nerves and the coeliac ganglion were treated with topical capsaicin to denervate the sensory afferents. Surgical portal vein stenosis (PVS) was performed 3 weeks after denervation. Effectiveness of vagal afferent denervation was confirmed by absent oesophagus to brainstem transfer of the neural tracer cholera toxin-conjugated horseradish peroxidase. Fos, the protein product of the c-fos gene, was detected by immunohistochemistry in central cardiovascular regulatory nuclei. Vagal nerve activity was measured after acute portal hypertension induced by an inflatable cuff around the portal vein. Cardiac output and mean arterial pressure were recorded.

RESULTS

In vagal capsaicin-treated rats, no horseradish peroxidase was detected in the brainstem after oesophageal injection. In vagal capsaicin-treated rats subjected to PVS, Fos expression was significantly decreased in both the solitary tract nucleus and paraventricular nucleus compared with untreated PVS rats. Acute portal hypertension stimulated vagal nerve electrical activity. The hyperdynamic circulation was completely abrogated in vagal capsaicin-treated PVS rats. Capsaicin induced no neural or haemodynamic changes in either sham-operated controls or coeliac ganglion-treated PVS rats.

CONCLUSION

In portal hypertensive rats, central cardiovascular regulatory nuclei initiate hyperdynamic circulation in response to a gut signal associated with portal hypertension. Portal hypertension signals to the central nuclei via capsaicin-sensitive vagal afferent nerves.

Subclinical Cushing's syndrome associated with an adrenocortical oncocytoma

Oncocytoma is a neoplasm that can arise in several organs, and it has been more commonly described in the kidney, salivary gland and thyroid. Oncocytoma arising in the adrenal gland is a rare finding. Moreover, functioning adrenocortical oncocytoma is exceptionally rare. A 47-yr-old man was incidentally discovered to have a right adrenal mass. The patient had no clinical features suggestive of increased adrenal function. However, hormonal evaluation showed a disturbed cortisol circadian rhythm, supranormal urinary cortisol excretion, a low level of ACTH, and a lack of suppressibility of cortisol secretion after dexamethasone. Right adrenalectomy was performed, and this revealed a well-circumscribed dark-brown tumor that measured 2.4x2.2 cm. The tumor consisted almost exclusively of large eosinophilic and epitheloid cells whose cytoplasm was packed with eosinophilic granulations, which corresponded to the numerous mitochondria confirmed on electron microscopy. This is a rare case of subclinical Cushing's syndrome that was caused by adrenocortical oncocytoma.

Measurement of whole blood phagocyte chemiluminescence in a microtitreplate format

Zymosan-induced luminol-enhanced chemiluminescence of phagocytes was measured in whole blood using a microtitreplate format. A consistent reaction response curve could be obtained using a normal blood sample, with low intra-assay variations in peak light index, cumulated response as well as time taken to reach the peak. Variations were common when tests were done on different days for the same individual, or when different persons were compared simultaneously. Reactions were hastened and enhanced if continuous shaking at 37 degrees C was applied. The interval between time zero and peak was the most consistent variable, with a coefficient of variation of 12% in inter-assay analysis. Because of its simplicity and ease of operation, the method is potentially useful in studying phagocyte functions in pathological states.

Histological benefits of virological response to peginterferon alfa-2a monotherapy in patients with hepatitis C and advanced fibrosis or compensated cirrhosis

BACKGROUND

Patients with chronic hepatitis C virus and advanced fibrosis or cirrhosis are at risk for disease progression and hepatic decompensation.

AIM

To determine the effects on hepatic histology of treatment with peginterferon alfa-2a (90 or 180 mug/week) or interferon alfa-2a (3 million units three times weekly) for 48 weeks in patients with paired biopsies.

METHODS

Liver biopsies were obtained at baseline and 6 months after end of treatment. Histological and virological responses were compared.

RESULTS

Patients attaining sustained virological response (n = 40) demonstrated the greatest improvements in fibrosis (-1.0, P < 0.0001) and inflammation (-0.65, P < 0.0001). Patients who cleared hepatitis C virus during treatment, but later relapsed (n = 59), experienced less improvement in fibrosis (-0.04, P < 0.0001) and inflammation (-0.14, P = 0.0768). Nonresponders (n = 85) showed no significant improvement in inflammation or fibrosis. Multiple regression analysis showed that the only factors contributing to improvement in fibrosis were sustained virological response (vs. nonresponder, P = 0.0005; vs. relapse, P = 0.7525) and body mass index < or =30 kg/m2 (P = 0.0995).

CONCLUSIONS

These findings indicate that virological response to peginterferon alfa-2a improves inflammation and fibrosis in hepatitis C virus patients with advanced fibrosis or cirrhosis. Improving virological response and maintaining ideal body weight are critical for achieving optimal histological outcomes in hepatitis C virus patients.

Screening of active ingredients of herbal medicine for interaction with CYP450 3A4

A two-step algorithm is adopted in the screening of herbal species which possess significant inhibitory effects on cytochrome P450 3A4 (CYP450 3A4). The algorithm comprises an initial stage of high throughput screening with Herbochip for the identification of herbal fractions that exhibit interactions with CYP450 3A4. Fifty commonly used TCM species were screened with seven showing a positive signal reflecting interaction. In the inhibition assays that followed, six of the seven species gave a signal. Sophora flavescens stood out as it gave the highest number of wells with a response, the highest maximum index was 0.96, and the median index was 0.55. The selection of TCM species with inhibitory effects on CYP450 carries the potential role of its use to boost the effects of known therapeutic agents, a mechanism that has been exploited in the design of regimens for the treatment of HIV infection.

Public knowledge, attitudes and behavior on antibiotic use: a telephone survey in Hong Kong

BACKGROUND

This study aimed to examine public knowledge, attitudes and behaviors regarding antibiotic use in the community of Hong Kong.

METHODS

A cross-sectional phone survey was conducted in 2006 on people aged 18 or older who were uninstitutionalized Hong Kong residents regarding antibiotic use for upper respiratory tract infections (URTIs).

RESULTS

A total of 1,002 respondents participated in the survey and 77%, 72% and 85% of the respondents had adequate knowledge, appropriate attitude/belief and behavior on antibiotic use, respectively. Some respondents (26%) believed that antibiotic was needed for symptoms of URTIs if they felt sick enough to seek medical care and 8% would share antibiotic with family members. Eighty-nine (9%) respondents had acquired antibiotic without a prescription. During the most recent episode of URTI, 78% had completed the antibiotic treatment course. Stepwise multiple logistic showed that higher education level and family income were associated with adequate patient knowledge. Male gender was a predictor of poor behavior on antibiotic use. Appropriate belief was associated with tertiary level of education or above.

CONCLUSIONS

Over 70% of the present cohort showed adequate knowledge, appropriate attitudes/beliefs and behavior on antibiotic use. Despite a small percent (8%-9%) of respondents reportedly shared and/or self-prescribed antibiotics, this would translate into the practice of half a million people in Hong Kong. Public education programmes should therefore be developed, targeting specific areas of misconceptions, misuse of antibiotic and vulnerable groups at risk of improper use of antibiotics.

Exploring differences in response to treatment with peginterferon alpha 2a (40kD) and ribavirin in chronic hepatitis C between genotypes 2 and 3

Chronic hepatitis C virus (HCV) infections with genotype 2 or 3 are associated with favourable sustained virologic response (SVR) rates. However, genotype 3 may respond less well. We reassessed all treatment-naive patients with genotype 2 and 3 participating in a large expanded-access, non-randomized, open-label trial, evaluating 180microg pegylated interferon (peg-IFN) alpha-2a (40kD) once weekly and 800 mg/day ribavirin for 24-48 weeks. Factors measured prior to initiation of antiviral therapy were considered in the multiple logistic regression model for predicting SVR. In total, 180 patients were analysed of which 72 (40%) were infected by genotype 2 and 108 (60%) genotype 3. The baseline characteristics between patients infected by genotype 2 or 3 were no different including the distribution of hepatic fibrosis stages by METAVIR score. Overall SVR was lower in those patients infected with genotype 3. The significant multivariate predictors of lack of SVR were hepatic fibrosis (P = 0.014) and genotype 3 (P = 0.030). The negative impact of cirrhosis (METAVIR score F4) on treatment response was more evident among subjects with genotype 3 than those with genotype 2 (P = 0.027). There is significant interaction between cirrhosis and genotype 3 leading to a poor antiviral response in such patients requiring an alternate management strategy. This finding should be confirmed in a larger population.

Prognostic significance of p53 gene mutations and protein overexpression in localized gastrointestinal stromal tumours

AIMS

Mutation of c-kit is a relatively early event in the tumorigenesis of gastrointestinal stromal tumours (GISTs). The aim was to determine the prognostic significance of p53 alterations as an additional genetic change in GISTs.

METHODS AND RESULTS

We reviewed 125 patients with localized GISTs subjected to complete resection between 1990 and 2002. Mutational analyses of c-kit exons 9, 11, 13 and 17, p53 exons 4-8 and immunohistochemistry for p53 protein were conducted using paraffin-embedded tissues. Alterations of p53 were observed in 50 patients (40.0%). Based on the National Institutes of Health's risk category, p53 alterations were noted more frequently in the higher risk categories (P = 0.041). With a median follow-up of 56.5 months (range: 2.3-126.8), 5-year relapse-free survival (RFS) rates were 61.7% without p53 alterations, compared with only 40.2% with p53 alterations (P = 0.009). Multivariate analysis indicated that p53 alterations comprised an independent, poor prognostic factor for RFS, in addition to c-kit mutations, large size, a high mitotic count and non-gastric primary sites.

CONCLUSIONS

Alterations in p53 were more commonly observed in localized GISTs at higher risk of relapse. This suggests that they are significant as an independent, poor prognostic factor.

Binge eating is associated with right orbitofrontal-insular-striatal atrophy in frontotemporal dementia

BACKGROUND

Neurophysiologic studies on human and nonhuman primates implicate an orbitofrontal-insular-striatal circuit in high-level regulation of feeding. However, the role of these areas in determining feeding disturbances in neurologic patients remains uncertain.

OBJECTIVE AND METHODS

To determine brain structures critical for control of eating behavior, we performed a prospective, laboratory-based, free-feeding study of 18 healthy control subjects and 32 patients with neurodegenerative disease. MR voxel-based morphometry (VBM) was used to identify regions of significant atrophy in patients who overate compared with those who did not.

RESULTS

Despite normal taste recognition, 6 of 32 patients compulsively binged, consuming large quantities of food after reporting appropriate satiety. All six patients who overate were clinically diagnosed with frontotemporal dementia (FTD), a disorder previously associated with disordered eating, while the nonovereaters were diagnosed with FTD, semantic dementia, progressive aphasia, progressive supranuclear palsy, and Alzheimer disease. VBM revealed that binge-eating patients had significantly greater atrophy in the right ventral insula, striatum, and orbitofrontal cortex.

CONCLUSION

Binge eating can occur despite reported satiety and is associated with damage to a right-sided orbitofrontal-insular-striatal circuit in humans. These findings support a model in which ventral insular and orbitofrontal cortices serve as higher-order gustatory regions and cooperate with the striatum to guide appropriate feeding responses.

Rapid spread of methicillin-resistant Staphylococcus aureus in a new hospital in the broad-spectrum antibiotic era

OBJECTIVES

It has been known that it takes a long time for methicillin-resistant Staphylococcus aureus (MRSA) to introduce and become endemic within a hospital. During the last decade, widespread use of broad-spectrum antibiotics might have affected the time required for MRSA to spread and become endemic in hospitals. However, there has been no report on this issue. We investigated how fast MRSA has spread and become endemic in a hospital opened in the broad-spectrum antibiotic era.

METHODS

The study was performed at a Korean hospital, which opened in 1999. We examined the change of antimicrobial susceptibility and antimicrobial use density (AUD) for 6 years since hospital opening.

RESULTS

S. aureus susceptibility to oxacillin decreased from 64% in the first month to 33% in the second month (P=.05), and then has maintained around 30%. AUD was remarkably high from the first year, in which total AUD and those of aminopenicillins, second-generation cephalosporins, fluoroquinolones, and macrolides were 4674.6, 1444.6, 1700.9, 421.3, and 520.0 DDD/1000 patient-days, respectively.

CONCLUSIONS

MRSA has spread within a few months in a hospital opened in the broad-spectrum antibiotic era. Excessively high use of broad-spectrum antibiotics seems to be responsible for rapid spread of MRSA in the hospital.

Analysis of percutaneous transhepatic cholangioscopy-related complications and the risk factors for those complications

BACKGROUND AND STUDY AIMS

Percutaneous transhepatic cholangioscopy (PTC) is being increasingly used for patients with biliary tract diseases. The aim of this study was to assess the safety of this procedure, and we systematically analyzed PTC-related complications and the risk factors for those complications.

PATIENTS AND METHODS

A total of 364 patients who underwent PTC were included in the study. The initial diagnoses, the indications for PTC, the complications that occurred during the procedures, and the risk factors for these complications were retrospectively analyzed.

RESULTS

The overall incidence of complications was 12.9 % for percutaneous transhepatic biliary drainage (PTBD), 12.8 % for tract dilation, and 6.9 % for tract maturation. Complications developed in 58/848 PTC sessions (6.9 %). Cholangitis and bacteremia were associated with PTBD and tract dilation, catheter migration and blockage with tract maturation, and bile duct injury with PTC. Mild complications occurred in 80 patients (22.2 %) during the preparation stages and in 43 sessions (5.1 %) during the PTC itself. Severe complications, including severe hemobilia, hemoperitoneum, rupture of the sinus tract, and ductal injury developed in 17 patients (4.7 %) during the preparation period, and in 15 patients (4.1 %) during PTC. The overall incidence of severe complications along the entire course was 8.2 % (30/364 patients). No patient died or required surgery. Intraductal manipulations, such as electrohydraulic lithotripsy or balloon dilation, and the first session of PTC were risk factors for procedure-related complications.

CONCLUSIONS

PTC is a relatively safe and well-tolerated method for treating certain biliary tract diseases. Meticulous patient selection and a cooperative team approach are required in order to minimize the incidence of complications and to provide effective management.

Evaluation of an in-house genotyping resistance test for HIV-1 drug resistance interpretation and genotyping

INTRODUCTION

The human immunodeficiency virus type 1 (HIV-1) genotyping resistance test (GRT) has been considered essential for HIV-1 drug resistance monitoring. However, it is not commonly used in some developing countries in Asia and Africa due to its high running cost.

OBJECTIVE

This study aims to evaluate a new low-cost in-house GRT for both subtype B and non-B HIV-1.

STUDY DESIGN

The in-house GRT sequenced the entire protease and 410 codons of reverse transcriptase (RT) in the pol gene. Its performance on drug resistance interpretation was evaluated against the FDA-approved ViroSeq HIV-1 Genotyping System. Particularly, a panel of 235 plasma samples from 205 HIV-1-infected patients in Hong Kong was investigated. The HIV-1 drug resistance-related mutations detected by the two systems were compared. The HIV-1 subtypes were analyzed through the REGA HIV-1 Genotyping Tool and env phylogenetic analysis.

RESULTS

Among the 235 samples, 229 (97.4%) were successfully amplified by both in-house and ViroSeq systems. All PCR-negative samples harbored viral RNA at <400 copies/mL. The in-house and ViroSeq system showed identical drug resistance-related mutation patterns in 216 out of 229 samples (94.3%). The REGA pol genotyping results showed 93.9% (215/229) concordance with the env phylogenetic results including HIV-1 subtype A1, B, C, D, G, CRF01_AE, CRF02_AG, CRF06_cpx, CRF07_BC, CRF08_BC, CRF15_01B and other recombinant strains. The cost of running the in-house GRT is only 25% of that for the commercial system, thus making it suitable for the developing countries in Asia and Africa.

CONCLUSIONS

Overall, our in-house GRT provided comparable results to those of the commercial ViroSeq genotyping system on diversified HIV-1 subtypes at a more affordable price which make it suitable for HIV-1 monitoring in developing countries.

Induction versus noninduction antiviral therapy for chronic hepatitis C virus in patients with congenital coagulation disorders: a Canadian multicentre trial

BACKGROUND

Patients with congenital coagulation disorders and chronic hepatitis C virus (HCV) infection have multiple risk factors (ie, infection predominantly with genotype-1 HCV, long duration of the disease, HIV coinfection and male sex) for poor response to antiviral therapy. The present study compared induction therapy with interferon-alpha (IFN-alpha)-2b with standard IFN-alpha2b therapy. Pegylated IFN was not available at the time that the study was initiated.

PATIENTS AND METHODS

A randomized study was performed comparing the efficacy of traditional IFN-alpha2b therapy (group A -- three million units, three times weekly for 24 to 48 weeks) and daily ribavirin (1.0 g to 1.2 g according to weight for 24 to 48 weeks), with induction IFN-alpha2b therapy (group B -- three million units, daily for eight weeks followed by the same dose administered three times a week for a further 16 to 40 weeks) and daily ribavirin (same dose as above) in IFN-naive patients with congenital coagulation disorders and chronic HCV infection.

RESULTS

Between 2000 and 2003, 54 HIV-negative patients were recruited and randomly assigned to group A or B (n=27 each). Both groups were comparable in terms of age, sex, ethnicity, body mass index, baseline HCV RNA titre, viral genotype, liver fibrosis stage and type of coagulation disorder. Induction therapy did not significantly alter sustained virological response rates (group A 50%, group B 50%; P=1.0). Multiple logistic regression analysis indicated that induction therapy did not benefit individuals with difficult-to-treat infection (ie, those infected with genotypes 1 and 4, or those with high baseline viral loads).

CONCLUSIONS

There was no benefit with induction antiviral therapy for HCV infection in individuals with congenital coagulation disorders.

Clinicopathological review of 61 patients with early bile duct cancer

AIMS

The concept of early cancer is already established in the hollow viscus. However, there is no broadly accepted concept of early bile duct cancer. We aimed to assess whether early bile duct cancer patients have characteristic clinicopathological features and a better prognosis compared with patients with advanced bile duct cancer.

MATERIALS AND METHODS

Between June 1996 and December 2004, 614 patients were histologically confirmed with primary bile duct cancers after resection. Extrahepatic early bile duct cancers are defined as carcinoma where invasion is confined within the fibromuscular layer of the extrahepatic bile duct. Intrahepatic early bile duct cancers arising from intrahepatic large bile ducts are also defined as carcinoma confined within the fibromuscular layer. We retrospectively reviewed medical records to obtain demographic, laboratory, radiological and pathological data.

RESULTS

Sixty-one (10%) patients were categorised with early bile duct cancers. They were frequently detected at asymptomatic (39%) or non-icteric (84%) stages. The most common gross type was the intraductal-growing type (58%). Not otherwise specified adenocarcinoma was only 67%, whereas papillary carcinoma was 31% of cancers. No lymph node metastasis and no lymphovascular/perineural invasions were noted in 89% of patients. The 5-year survival rate for early bile duct cancer was excellent (80%).

CONCLUSIONS

Although early bile duct cancer is not a common disease, it is not a very rare entity either. The clinicopathological features of early bile duct cancer patients differ from those of advanced bile duct cancer patients, with asymptomatic clinical presentation, different macroscopic and microscopic findings, and excellent prognosis.

Endoscopic removal of biliary self-expandable metallic stents: a prospective study

BACKGROUND AND STUDY AIMS

The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs.

PATIENTS AND METHODS

30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session.

RESULTS

The covered SEMSs were easily removed in 19 out of 22 patients (86.4 %), whereas none of the eight uncovered SEMSs (0 %) could be removed. The only factor predicting successful stent removal was the presence of a stent covering ( P = 0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents.

CONCLUSIONS

In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.

Association of nodular regenerative hyperplasia of the liver with porto-pulmonary hypertension in a patient with systemic lupus erythematosus

A 37-year old woman with systemic lupus erythematosus (SLE) complicated by pulmonary hypertension (PHT) was admitted to evaluate abnormal liver function. Radiological imaging study, including ultrasonography, computed tomography and magnetic resonance imaging and upper gastrointestinal endoscopy, revealed multiple hepatic nodules, hepatosplenomegaly and esophageal varices. Percutaneous needle liver biopsy showed non-cirrhotic hepatic nodules with hyperplastic hepatocytes surrounded by atrophic hepatocytes, confirming the diagnosis of nodular regenerative hyperplasia (NRH) associated with non-cirrhotic portal hypertension (PT). NRH of the liver is known to be a very rare hepatic manifestation in rheumatic diseases. This case shows the association of NRH with porto-pulmonary hypertension in SLE.

Pineal gland metabolism in patients with adolescent idiopathic scoliosis

The scoliosis observed in chickens after pinealectomy resembles that seen in humans with an adolescent idiopathic scoliosis, suggesting that melatonin deficiency may be responsible. However, to date there have been no studies of pineal gland glucose metabolism in patients with adolescent idiopathic scoliosis that might support this hypothesis.

We examined the excretion of urinary 6-sulfatoxyl-melatonin as well as the glucose metabolism of the pineal gland in 14 patients with an adolescent idiopathic scoliosis and compared them with those of 13 gender-matched healthy controls using F-18 fluorodeoxyglucose brain positron emission tomography. There was no significant difference in the level of urinary 6-sulfatoxyl-melatonin or pineal gland metabolism between the study and the control group. We conclude that permanent melatonin deficiency is not a causative factor in the aetiology of adolescent idiopathic scoliosis.

Family physicians' experiences, behaviour, and use of personal protection equipment during the SARS outbreak in Singapore: do they fit the Becker Health Belief Model?

Singapore experienced the SARS outbreak in 2003. The study aimed to describe the experience and behaviour of family physicians and the use of personal protection equipment (PPE) in their encounters with SARS patients. 8 such participants were interviewed and the content was analysed using qualitative research method. They highlighted the difficulties in procuring PPE due to severe shortage, the discomfort and inconvenience associated with its use. Despite the increasing operating cost, declining patient attendance and high price of the PPE, they persist in using PPE and change their behaviour in order to reduce the perceived threat to their lives. It fits into the Becker Health Belief Model, which explains that behaviour change depends on the balance of perceived vulnerability, severity, effectiveness, and barriers. The vulnerability and severity of SARS to healthcare workers were verified by the hospital experience. Perceived effectiveness of PPE amongst the family physicians outweighed the barriers of shortage, cost and discomfort of the PPE.

Emerging invasive liver abscess caused by K1 serotype Klebsiella pneumoniae in Korea

OBJECTIVES

The high incidence of invasive liver abscess caused by Klebsiella pneumoniae in Taiwan, contrasted with the rareness of this disease in Western countries, has aroused special interest. There have been few detailed reports from other Asian countries. To investigate a current epidemiology of K. pneumoniae liver abscess in Korea and to determine K serotype distribution in K. pneumoniae strains causing liver abscess, we performed a nationwide prospective study.

METHODS

Community-acquired, culture-proven liver abscess cases were enrolled between 2004 and 2005. Etiologies and clinical features were analyzed. K. pneumoniae isolates were serotyped according to K antigen. Meta-analysis was done to determine the time trend of the etiologies of liver abscess in Korea.

RESULTS

Out of 371 cases collected prospectively, 290 (78.2%) were caused by K. pneumoniae. Most K. pneumoniae liver abscesses were monomicrobial. Diabetes mellitus was the most common underlying disease (39.9%). Distant metastatic infections were frequently observed (8.7%). magA PCR revealed that 95 (59.4%) out of 160 K. pneumoniae isolates belonged to the K1 serotype.

CONCLUSIONS

Our study indicates that K. pneumoniae has emerged as a major etiologic agent of liver abscess in Korea, and these emerging infections seem to be attributable to invasive K. pneumoniae strains with capsular K1 serotype.

Endoscopic removal of biliary self-expandable metallic stents: a prospective study

BACKGROUND AND STUDY AIMS

The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs.

PATIENTS AND METHODS

30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session.

RESULTS

The covered SEMSs were easily removed in 19 out of 22 patients (86.4 %), whereas none of the eight uncovered SEMSs (0 %) could be removed. The only factor predicting successful stent removal was the presence of a stent covering ( P = 0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents.

CONCLUSIONS

In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.

Peginterferon alfa-2a (40KD) plus ribavirin in chronic hepatitis C patients who failed previous interferon therapy

BACKGROUND

The management of patients with chronic hepatitis C who have relapsed or failed to respond to interferon based therapies is an important issue facing hepatologists.

AIMS

We evaluated the efficacy and safety of peginterferon alfa-2a (40KD) plus ribavirin in this population by conducting a multicentre open label study.

PATIENTS

Data from adults with detectable serum hepatitis C virus (HCV) RNA who had not responded or had relapsed after previous conventional interferon or conventional interferon/ribavirin combination therapy were analysed.

METHODS

Patients were retreated with peginterferon alfa-2a (40KD) 180 microg/week plus ribavirin 800 mg/day for 24 or 48 weeks at the investigators' discretion. The study was conceived before the optimal dose of ribavirin (1000/1200 mg/day) for patients with genotype 1 was known. The primary endpoint was sustained virological response (SVR), defined as undetectable HCV RNA (<50 IU/ml) after 24 weeks of follow up. The analysis was conducted by intention to treat.

RESULTS

A total of 312 patients (212 non-responders, 100 relapsers) were included. Of these, 28 patients were treated for 24 weeks and 284 for 48 weeks. Baseline characteristics between non-responders and relapsers were similar although more non-responders had genotype 1 infection (87% v 69%). Overall SVR rates were 23% (48/212) for non-responders and 41% (41/100) for relapsers. When data were analysed by genotype, SVR rates were 24% (61/253) in genotype 1 and 47% (28/59) in genotype 2/3.

CONCLUSIONS

These results in a large patient cohort demonstrate that it is possible to cure a proportion of previous non-responders and relapsers by retreating with peginterferon alfa-2a (40KD) plus ribavirin.