Development of an Enzyme-Linked Immunosorbent Assay for Rapid Detection of Dengue Virus (DENV) NS1 and Differentiation of DENV Serotypes during Early Infection.

Dengue fever, caused by infections with the dengue virus (DENV), affects nearly 400 million people globally every year. Early diagnosis and management can reduce the morbidity and mortality rates of severe forms of dengue disease as well as decrease the risk of wider outbreaks. Although the early diagnosis of dengue can be achieved using a number of commercial NS1 detection kits, none of these can differentiate among the four dengue virus serotypes. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) for the detection of dengue virus (DENV) NS1 by pairing a serotype-cross-reactive monoclonal antibody (MAb) with one of four serotype-specific MAbs in order to facilitate the rapid detection of NS1 antigens and the simultaneous differentiation of DENV serotypes. A total of 146 serum samples obtained from patients suspected to be in the acute phase of DENV infection were used to evaluate the clinical application of our novel test for the detection and serotyping of DENV. The overall sensitivity rate of our test was 84.85%, and the sensitivity rates for serotyping were as follows: 88.2% (15/17) for DENV serotype 1 (DENV1), 94.7% (18/19) for DENV2, 75% (12/16) for DENV3, and 66.6% (6/9) for DENV4. Moreover, there was no cross-reactivity among serotypes, and no cross-reactivity was observed in sera from nondengue patients. Thus, our test not only enables the rapid detection of the dengue virus but also can distinguish among the specific serotypes during the early stages of infection. These results indicate that our ELISA for DENV NS1 is a convenient tool that may help elucidate the epidemiology of DENV outbreaks and facilitate the clinical management of DENV infections.

Longitudinal investigation of ischemic stroke using magnetic resonance imaging: Animal model.

BACKGROUND: Arterial embolism is a major cause of ischemic stroke. Currently, digital subtraction angiography (DSA) is the gold standard in clinical arterial embolization examinations. However, it is invasive and risky. OBJECTIVE: This study aims to longitudinally assess the progression of carotid artery embolism in middle cerebral artery occlusion animal model (MCAO) using magnetic resonance imaging (MRI) techniques. METHODS: Turbo spin echo (TSE), time of flight magnetic resonance angiography (TOF-MRA) and diffusion weighted magnetic resonance imaging (DWI) were used to evaluate the image characteristics of cerebral tissues at 1, 2, 3, 7, 14, 21 and 28 days after MCAO microsurgery on Sprague-Dawley (SD) rats. Quantitative analysis was performed and compared in MCAO hemisphere and contralateral normal hemisphere. Furthermore, pathologic section using triphenyl tetrazolium chloride (TTC) stain was performed as well. RESULTS: TOF-MRA showed carotid signal void in the embolism side, which is evidence of artery occlusion. The used MRI techniques showed that edema gradually dissipated within one week, but there was no significant change afterwards. The time-varying signal intensity of MRI techniques in MCAO hemisphere changed significantly, but there were no significant changes in contralateral normal hemisphere. Cerebral injury was also confirmed by analysis of pathology images. CONCLUSIONS: The MCAO animal model was successfully established on SD rats using the microsurgery to assess arterial embolization of intracranial tissue injury.

Emphysematous cholecystitis presenting as gas-forming liver abscess and pneumoperitoneum in a dialysis patient: a case report and review of the literature.

BACKGROUND: Emphysematous cholecystitis is a rare variant of acute cholecystitis with a high mortality rate. The combination of emphysematous cholecystitis, liver abscess and pneumoperitoneum are even rarer. Herein we present a case of emphysematous cholecystitis in a senile diabetic lady who had worsening hemodynamics while undergoing hemodialysis. CASE PRESENTATION: A 64-year-old woman with history of type 2 diabetes mellitus and end stage renal disease with regular hemodialysis presented to the emergency department with a 1-day history of sudden onset of lassitude and hypotension during hemodialysis. The result of a computed tomography (CT)-scan revealed air encircling the gallbladder, liver parenchymal and minimal pneumoperitoneal and liver abscess with no cholelithiasis. The patient had received empirical antibiotics with piperacillin-tazobactam 2.25 g intravenous route every 6 h for 14 days and cholecystectomy with surgical debridement and lead an uneventful postoperative hospital course. Escherichia coli was demonstrated as well as blood culture and peritoneal fluid culture. CONCLUSION: In a senile diabetic and dialysis patient, we should take emphysematous cholecystitis into consideration once vague abdominal pain occurrs. Empirical antibiotic therapy and adequate surgical intervention should take place as soon as possible.

Plantar Purpura as the Initial Presentation of Viridians Streptococcal Shock Syndrome Secondary to Streptococcus gordonii Bacteremia.

Viridians streptococcal shock syndrome is a subtype of toxic shock syndrome. Frequently, the diagnosis is missed initially because the clinical features are nonspecific. However, it is a rapidly progressive disease, manifested by hypotension, rash, palmar desquamation, and acute respiratory distress syndrome within a short period. The disease course is generally fulminant and rarely presents initially as a purpura over the plantar region. We present a case of a 54-year-old female hospital worker diagnosed with viridians streptococcal shock syndrome caused by Streptococcus gordonii. Despite aggressive antibiotic treatment, fluid hydration, and use of inotropes and extracorporeal membrane oxygenation, the patient succumbed to the disease. Early diagnosis of the potentially fatal disease followed by a prompt antibiotic regimen and appropriate use of steroids are cornerstones in the management of this disease to reduce the risk of high morbidity and mortality.

Dysphagia aortica: a fatal delay in diagnosis.

Extrinsic esophageal compression leading to dysphagia is an uncommon and late presentation of large thoracic aortic aneurysm named dysphagia aortica. Herein, we report an 86-year-old man who presented with 1-week duration of chest pain, backache, and dysphagia and was eventually diagnosed as dysphagia aortica. Our patient developed progressive dyspnea due to tracheal compression and failed surgery. The case illustrates the importance of early identification of the rare entity of dysphagia especially in elderly cases with cardiovascular disease with complaint of undetermined dysphagia accompanied with chest pain and backache.

The high prevalence of Legionella pneumophila contamination in hospital potable water systems in Taiwan: implications for hospital infection control in Asia.

BACKGROUND: The major sources of Legionnaires' disease (LD) are the potable water systems of large buildings including hospitals, nursing homes, and hotels. Culturing the hospital water system for Legionella allows a preventive approach for hospital-acquired LD. However, hospital-acquired LD is rarely reported in Taiwan, and environmental cultures of Legionella in hospital water systems in Taiwan have never been systematically performed. OBJECTIVE: The objective of this study was to determine if Legionella is present in hospital water systems in Taiwan. Water quality analysis was also performed to determine if geographic differences in water quality result in different Legionella positivity rates. METHOD: The water systems of 16 hospitals throughout Taiwan were tested for Legionella by culture. Standardized culture procedures were followed. RESULTS: Legionella pneumophila was isolated from 63% (10/16) of the hospital water systems; 19% (3/16) of the hospitals had an L. pneumophila positive rate greater than 30%. L. pneumophila serogroups 1 and 6 (strains that are most responsible for Legionella infections) were isolated from 80% (8/10) and 60% (6/10), respectively, of the hospitals that yielded L. pneumophila in their water distribution systems. CONCLUSION: As was shown in epidemiological studies in the USA and Spain, hospital-acquired legionellosis may be prevalent but underdiagnosed in Taiwan.

Rapid diagnosis of bacterial meningitis using a microarray.

BACKGROUND/PURPOSE: Microarrays, or biochips, are a new technology that can allow rapid detection of bacterial genetic materials. To explore their practical applications, we compared use of a microarray for the diagnosis of bacterial meningitis with the traditional blood and cerebrospinal fluid (CSF) culture methods. METHODS: Samples from 50 patients with suspected bacterial meningitis were analyzed by microarray and by traditional blood and CSF cultures. RESULTS: Among all samples, 11 were positive by microarray analysis, seven were positive by CSF bacterial culture and six were positive by blood culture. CSF pleocytosis was found in 26 patients. Of these, eight were positive by microarray analysis, seven were positive by CSF culture and five were positive by blood culture. The percentage of positive results from microarray analysis was 22%, compared to 14% by CSF culture and 12% by blood culture. The CSF bacterial culture method had the highest positive predictive value and specificity (both 100%). The sensitivity of microarray analysis was higher (30.8%) than that of CSF and blood cultures (26.9% and 19.2%). All three methods had a similar negative predictive value in the range of 52.3-55.8%. Of the 11 microarray positive samples, four were identified successfully in CSF culture (36.4%) and three samples were identified in blood culture (27.2%). One of the microarray positive samples was diagnosed as a polymicrobial infection (9%), and the rest were monomicrobial infections. CONCLUSION: The microarray method provides a more accurate and rapid diagnostic tool for bacterial meningitis compared to traditional culture methods. Clinical application of this new technique may reduce the potential risk of delay in treatment.

Dysthymia increases the risk of temporomandibular disorder: A population-based cohort study (A STROBE-Compliant Article).

Numerous studies have investigated the relationship between depression and temporomandibular disorders (TMD), but the conclusions remain vague. The aim of this study was to examine the causal effect between depression and TMD.The reporting of this study conforms to the STROBE statement. In this retrospective cohort study, all samples were recruited from a representative subdataset of 1 million insured persons for the year 2005 Longitudinal Health Insurance Database, who were randomly selected from all beneficiaries enrolled in the National Health Insurance program of Taiwan. We used a propensity score and stratified 926,560 patients into 2 groups (propensity1 = 588,429 and propensity2 = 338,131) and 4 cohorts (propensity1 with depression = 18,038, propensity1 without depression = 570,391, propensity2 with depression = 38,656, propensity2 without depression = 299,475) to detect the development of TMD among the depressive and nondepressive patients between 2004 and 2013.The positive correlative factors of TMD included female, total number of times seeking medical advice (TTSMA) for anxiety state, TTSMA for generalized anxiety disorder, TTSMA for mandible fracture, and TTSMA for unspecified anomaly of jaw size. The propensity2 group was represented by elder and female-predominant patients who used more psychiatric health resources. Among 3 types of depression, only dysthymia (so-called chronic depression) had a causal impact on TMD in the propensity 2 group. In the propensity 2 group, the hazard ratio of dysthymia for TMD measured by Cox's regression was 1.64 (95% confidence interval 1.28-2.09), after adjusting for demographic factors, psychiatric comorbidities, and maxillofacial confounders. The first-onset mean time of TMD as the consequence of dysthymia was 3.56 years (sd = 2.74, min = 0.08, median = 2.99, max = 9.73).This study demonstrates that dysthymia increases the risk of TMD in elderly and female-predominant patients who use more psychiatric health resources.

Invasive liver abscess syndrome predisposed by Klebsiella pneumoniae related prostate abscess in a nondiabetic patient: a case report.

BACKGROUND: Prostate abscess is usually a complication of acute urinary tract infection. Invasive liver abscess syndrome is characterized with Klebsiella pneumoniae related multiple organ metastasis. Concomitant pyogenic liver abscess and prostate abscess have rarely been reported. Recurrent episode of liver abscess is even rarer. CASE PRESENTATION: We report a 71-year-old male with acute bacterial prostate abscess and urinary tract infection caused by K. pneumoniae associated with multiple liver abscess, psoas muscle abscess and osteomyelitis. Blood culture and urine culture yielded K. pneumoniae, which confirmed the diagnosis of invasive liver abscess syndrome caused by K. pneumoniae. The patient was successfully treated with empirical antibiotics for 6 weeks. CONCLUSIONS: This case emphasizes the importance of timely and accurate diagnosis followed by appropriate treatment in disseminated K. pneumoniae infection to prevent significant morbidity and mortality.

Etiology of community acquired pneumonia among adult patients requiring hospitalization in Taiwan.

BACKGROUND: There has not been a comprehensive multi-center study investigating the microbial profile of community acquired pneumonia (CAP) in Taiwan. METHODS: A prospective study of adult CAP patients requiring hospitalization between December 2001 and April 2002 was carried out in 13 hospitals in Taiwan. Etiology was determined based on laboratory data from blood and sputum cultures plus serology from paired serum and urine antigen detection tests. RESULTS: Etiology was assigned to 99 (58.9%) of the 168 patients having the most complete data for etiology determination, with mixed infection in 21 (12.5%) patients. More than half (51.8%) of the patients were>60 years and 63.7% of the patients were males. The most common etiologic agent was Streptococcus pneumoniae (40, 23.8%), the majority (60%, 24 cases) of which was detected by positive urine antigen test. Other common agents included Mycoplasma pneumoniae (24, 14.3%), Chlamydia pneumoniae (12, 7.1%), Influenza A virus (11, 6.5%), Klebsiella pneumoniae (8, 4.8%) and Haemophilus influenzae (8, 4.8%). The prevalence of S. pneumoniae and M. pneumoniae was highest in patients>60 years (25/87, 28.7%), and<44 years (12/59, 19%), respectively; while K. pneumoniae comprised a larger proportion (4/22, 18%) in the 45-59 years group. CONCLUSIONS: S. pneumoniae was the most common etiology agent in adult patients hospitalized due to CAP in Taiwan and the spectrum of other major pathogens was similar to studies conducted elsewhere in the world. Empiric treatment recommendations developed in other parts of the world may be appropriately adapted for local use after taking into account local resistance profiles. Our data also support the recommendation that urine antigen test be added as an adjunct to adult CAP etiology diagnosis protocol.

Acute Respiratory Distress Syndrome Manifested by Leptospirosis Successfully Teated by Extracorporeal Membrane Oxygenation (ECMO).

Leptospirosis is recognized as a zoonotic disease that is emerging worldwide. Severe manifestations are associated with high morbidity and mortality rates and may therefore pose an important risk to public health, especially in certain high prevalence areas like Taiwan. The severe pulmonary form of leptospirosis is a lesser known entity and is characterized by intra-alveolar hemorrhage and can lead to acute respiratory failure with resistant hypoxemia, which leads to high mortality rates despite maximally invasive mechanical ventilation and adequate treatment. We herein present a case of severe leptospirosis complicated by massive pulmonary hemorrhage, which was successfully managed by extra corporeal membrane oxygenation.

Successful resolution of symmetrical peripheral gangrene after severe acute pancreatitis: a case report.

INTRODUCTION: Symmetrical peripheral gangrene is an uncommon but devastating complication in critically ill patients, and it has a high mortality. It is seen in a wide variety of medical conditions, presenting as symmetrical gangrene of two or more extremities without large blood vessel obstruction. CASE PRESENTATION: We report a case of a 44-year-old Chinese man who was diagnosed with alcohol-related severe acute pancreatitis and presented with systemic inflammatory response syndrome and intractable vomiting. On the fourth day of admission, the patient developed cyanosis and gangrene of the fingers bilaterally. His cyanosis and gangrene did not resolve despite tapering of the vasopressor treatment. Gradually, his digital gangrene improved after administration of anti-platelet medication and pentoxifylline. CONCLUSIONS: To the best of our knowledge, this is the first case report of symmetrical peripheral gangrene occurring after acute pancreatitis with successful resolution. We highlight the importance of prompt and aggressive fluid resuscitation and consideration of multiple treatment options to prevent a hypovolemic state caused by acute pancreatitis.

Novel Investigations of Flavonoids as Chemopreventive Agents for Hepatocellular Carcinoma.

We would like to highlight the application of natural products to hepatocellular carcinoma (HCC). We will focus on the natural products known as flavonoids, which target this disease at different stages of hepatocarcinogenesis. In spite of the use of chemotherapy and radiotherapy in treating HCC, patients with HCC still face poor prognosis because of the nature of multidrug resistance and toxicity derived from chemotherapy and radiotherapy. Flavonoids can be found in many vegetables, fruits, and herbal medicines that exert their different anticancer effects via different intracellular signaling pathways and serve as antioxidants. In this review, we will discuss seven common flavonoids that exert different biological effects against HCC via different pathways.

Non-septicemic Burkholderia pseudomallei liver abscess in a young man.

Melioidosis, caused by Burkholderia pseudomallei, has been increasingly recognized in Taiwan recently. Its isolation in liver abscess is rare compared to pulmonary melioidosis. We report a case of liver abscess due to B. pseudomallei in an immunocompetent 27-year-old male soldier admitted due to fever, sore throat and mild non-productive cough for 1 week. Physical examination was unremarkable except for congestion of the pharyngeal wall, moderate enlargement of the tonsils without pus coating, and palpable tender lymphadenopathy over bilateral submental regions. Antibiotic treatment with cefazolin 1 g every 8 hours intravenously was given without response. Left flank pain, followed by right flank pain associated with epigastric tenderness developed. Sonography and computed tomography scan of the abdomen demonstrated liver abscess. Aspiration of the liver abscess was performed and abscess culture yielded B. pseudomallei. Treatment with ceftazidime 2 g every 8 hours intravenously (4 weeks' duration) followed by oral regimens of amoxicillin-clavulanate was given. The patient was free of symptoms at 8 months' follow-up. Early awareness and definite diagnosis as well as institution of proper antimicrobial agents are imperative for successful treatment of melioidosis.

Antibiotic usage in community-acquired infections in hospitals in Taiwan.

BACKGROUND AND PURPOSE: Using an epidemiologically meaningful in-hospital population with community-acquired infections, we evaluated antibiotic therapy in terms of indication and choice of antibiotic and microbiologic work-up. METHODS: Infectious disease specialists evaluated charts of 436 patients from 9 hospitals and selected those who received antibiotics within 3 days of admission. Each antibiotic prescribed was marked for appropriateness of indication and choice. Microbiologic isolates were evaluated for their clinical significance. RESULTS: The most common infections were in the lower respiratory tract (46.1%). Each patient received a mean of 2.25 antibiotics for 8.1 +/- 6.4 days. Of the 975 courses of antibiotics given in the study period, indication and choice were correct in 37.4% and unsatisfactory in 14.5%. The vast majority of antibiotics used (79.2%) were first-line antibiotics--usually first-generation cephalosporins, aminoglycosides, and aminopenicillins. Most patients (66%) had a microbiology laboratory work-up, but only 37.4% were judged by evaluators to have a meaningful microbiologic diagnosis. Among the 201 patients with lower respiratory tract infections, 105 (52.2%) had a diagnosis of pneumonia. A positive isolate was recovered in 30 (28.6%) patients, and most of these isolates (20, 68.7%) were aerobic gram-negative rods. There were three positive blood cultures but none grew Streptococcus pneumoniae. CONCLUSIONS: Antibiotics were used excessively in number and duration. The microbiologic work-up had little effect on the indication and choice of antibiotics. Community-acquired pneumonia differed markedly from that in Western countries in that only 3.3% were caused by S. pneumoniae.

Pseudomonas aeruginosa endocarditis associated with endophthalmitis caused by arteriovenous fistula and graft infection.

Bacterial endocarditis due to Pseudomonas aeruginosa arising from arteriovenous (AV) fistula and graft infection is unusual. We report an uncommon case of a 55-year-old woman housewife with chronic glomerulonephritis who had received hemodialysis (HD) for 5 years. She was admitted due to frequent episodes of AV fistula and graft infections in the past 5 years. She was admitted to our hospital because of a fever of unknown origin. During hospitalization, cardiac sonography and transesophageal echocardiography (TEE) confirmed a vegetation over the mitral valve. Blood culture yielded Pseudomonas aeruginosa. Endophthalmitis of the right eye was diagnosed by funduscopy because of painful redness of the right eye with exudative discharge. The patient was treated with ceftazidime for 9 weeks. Since then, she has been well, without any sequale after 1 year of following up. Physicians should be aware of the possibility of infective endocarditis in an uremic patient who suffers from fever of unknown origin. Early diagnosis with an adequate tool such as TEE and appropriate treatment will lead to an excellent prognosis.

Molecular characterisation of multiple drug-resistant Acinetobacter baumannii isolates in southern Taiwan.

The purpose of this study was to develop a multiplex polymerase chain reaction (mt-PCR) assay for synchronous detection of carbapenem resistance genes and/or pandrug resistance genes in clinical isolates of multidrug-resistant Acinetobacter baumannii (MDR-AB) and to investigate the association between the genetic make-up and a drug-resistant pattern. In total, 213 MDR-AB isolates were collected. All clinical isolates underwent antimicrobial susceptibility testing and were analysed for the presence of oxacillinase genes (bla(OXA-23), bla(OXA-24), bla(OXA-51)-like and bla(OXA-58)), class A and C ß-lactamase genes (bla(TEM-1) and bla(AmpC), respectively), and an integron-associated antibiotic resistance gene (int1) by an in-house-designed mt-PCR assay. Of the 213 isolates, 73.87% harboured both bla(TEM-1) and bla(AmpC) and 83.92% carried at least three oxacillinase genes. Moreover, 64.82% of the isolates were significant in that they had two ß-lactamase genes and three oxacillinase genes (P<0.001), indicating the complexity of the genetic make-up of carbapenem-resistant A. baumannii. The bla(OXA-51)-like allele was detected in the majority of these A. baumannii isolates (97.49%), whereas bla(OXA-23) was rarely prevalent in these isolates. In multivariate logistic regression, the presence of bla(OXA-23) and bla(TEM-1) had a statistically significant association with imipenem resistance [bla(OXA-23), P=0.004, odds ratio (OR)=10.52, 95% confidence interval (CI) 2.12-52.17; bla(TEM-1), P=0.005, OR=6.14, 95% CI 1.74-21.62]. These results suggest that detecting bla(OXA-23) and bla(TEM-1) genes could be used to predict imipenem resistance in MDR-AB isolates. A mt-PCR for detecting carbapenem resistance genes and pandrug resistance genes of A. baumannii isolates was developed to provide an assay to quickly screen for potential imipenem-resistant A. baumannii in the clinic.