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Shan-Chwen Chang

Publications and source records attributed to Shan-Chwen Chang.

At least 73 records · Page 4Linked to original sources
PubMed2004

Sequential symptomatic analysis in probable severe acute respiratory syndrome cases.

STUDY OBJECTIVE: Previous reports on severe acute respiratory syndrome (SARS) described mainly its symptoms. However, the time sequence of symptom development was rarely discussed. The objective of this study is to chronologically document the time sequence of symptom development in probable SARS cases and compare that of the febrile non-SARS cases, thus providing valuable information for early recognition of the disease. METHODS: This prospective, descriptive, cohort study was conducted in an academic university hospital in Taipei, Taiwan, from March 14 through May 12, 2003. Patients presenting to the emergency department (ED) with a temperature of at least 38.0 degrees C (> or =100.3 degrees F) and exposure history were evaluated with a structured protocol. Detailed time sequences of individual symptoms were recorded, and chest radiography and laboratory test results were obtained. Probable SARS cases were determined by the Center of Disease Control Taiwan. Children younger than 15 years and suspected SARS patients with negative polymerase chain reaction results were excluded from final analysis. RESULTS: Seventy-nine SARS and 220 non-SARS cases were analyzed. The major clinical symptoms of SARS patients on ED presentation were myalgia, loose stool or diarrhea, nonproductive cough or dyspnea, headache, and chills. Upper airway symptoms, including rhinorrhea and sore throat, were rarely seen in the SARS patients but were common in the non-SARS group. Characteristic symptom sequence, consisting of initial fever accompanied by diarrhea and myalgia and then progressive respiratory symptoms, was identified in 55 SARS patients (69.6%; 95% confidence interval [CI] 0.60 to 0.80) but only 7 (3.2%; 95% CI 0.008 to 0.05) non-SARS patients. Chest radiographic abnormality may precede lower respiratory tract symptoms in some SARS patients. CONCLUSION: During an outbreak period, recognition of possible SARS cases depends on the heightened awareness of its clinical presentation. Aside from travel and contact history, the time sequence of the accompanying symptoms of SARS should help first-line physicians screen SARS patients at an early stage.

Adult↗
PubMed2004

Validation of a novel severe acute respiratory syndrome scoring system.

STUDY OBJECTIVE: In a pilot study conducted during March 14 to April 2, 2003, 2 severe acute respiratory syndrome (SARS) screening scores were developed for predicting SARS among febrile patients presenting to the emergency department (ED). The objective of this study is to validate these scoring systems with a different set of patients. METHODS: All adult patients with documented fever, measured at home or at the hospital, and presenting to the ED of National Taiwan University Hospital, a 2,400-bed tertiary care teaching hospital in northern Taiwan, were prospectively enrolled. Two previously developed SARS screening scores were applied to all patients. The final diagnosis of SARS was made by the Expert Committee of the Center for Disease Control Taiwan, Republic of China, according to the criteria of Centers for Disease Control and Prevention, Atlanta, GA. RESULTS: A total of 239 adult patients, including 117 men and 122 women, were enrolled. Eighty-two patients were finally diagnosed with SARS. Compared with the SARS patients in the derivation cohort, those in the validation cohort were older (44.5+/-15.9 versus 33.9+/-15.9 years), more likely to acquire the disease locally (76.8% versus 37.5%), and more likely to have cough before or during fever. For the non-SARS patients, cases in the validation cohort presented with less cough and coryza but more diarrhea. For the 4-item symptom score, the sensitivity reached 96.3% (95% confidence interval [CI] 89.7% to 98.7%) and the specificity 51.6% (95% CI 43.8% to 59.3%). For the 6-item clinical score, the sensitivity reached 92.6% (95% CI 84.8% to 96.6%) and the specificity 71.2% (95% CI 63.6% to 77.7%). When the clinical score was applied to patients with a positive symptom score, the combined sensitivity reached 90.2% (95% CI 82.0% to 95.0%), and the combined specificity reached 80.1% (95% CI 73.2% to 85.6%). CONCLUSION: This prospective study validated the scoring system previously developed by using a different cohort. The scoring systems could be applied to settings where mass screening of SARS is needed during future outbreaks.

Adolescent↗
PubMed2004

Using 18-fluoro-2-deoxyglucose positron emission tomography in detecting infectious endocarditis/endoarteritis: a preliminary report.

RATIONALE AND OBJECTIVES: We evaluated the effectiveness of positron emission tomography (PET) with 18-fluoro-2-deoxyglucose (FDG) in the detection of infectious endocarditis/endoarteritis. MATERIALS AND METHODS: For this study, we recruited 6 patients (4 women, 2 men; age range, 35 - 78 years; mean age, 55.8 +/- 16.8 years) who were clinically diagnosed as having infective endocarditis/endoarteritis by their echocardiographic findings and by Duke criteria. RESULTS: For all 6 patients, we also found increased FDG uptakes in the corresponding areas detected in echocardiography. CONCLUSION: FDG-PET appears to be a promising tool in diagnosing infective endocarditis/endoarteritis, and further prospective studies on a large scale to fully exploit the usefulness of FDG-PET for infective endocarditis/endoarteritis are needed.

Adult↗
PubMed2004

Severe acute respiratory syndrome.

PURPOSE OF REVIEW: Severe acute respiratory syndrome (SARS) is an infectious disease first recognized in November 2002 in Guangdong Province, China. It spread to many countries all over the world during February to June 2003, with 8098 cases reported. Twenty-one percent of the affected people were health care workers. Because SARS is a new emerging disease, this review describes the current understanding about the etiology, clinical pictures, laboratory and radiological findings of SARS. RECENT FINDINGS: Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) was quickly found to be the etiological agent of SARS in April 2003. The transmission of SARS-CoV between human beings is mainly due to close contact. Using barrier precautions, the transmission of SARS-CoV can be prevented. The most common clinical presentations of patients with SARS include fever, cough, and dyspnea. The common laboratory findings include lymphopenia, thrombocytopenia, elevated serum alanine and aspartate aminotransferase, lactate dehydrogenase, creatine phosphokinase, and C-reactive protein. The most common radiological finding is pneumonic lesion(s) in the chest radiogram. Many patients experience exacerbation of clinical symptoms in the second week of disease course and some may progress to respiratory failure and need mechanical ventilatory support. The overall case fatality rate is 9.6%. The current method of treatment of SARS is still controversial. SUMMARY: SARS is an infectious disease with high contagiousness and a high mortality rate. Early case identification and infection control are two important factors to limit its spread.

Communicable Diseases, Emerging↗
PubMed2004

Increasing prevalence of methicillin-resistant Staphylococcus aureus causing nosocomial infections at a university hospital in Taiwan from 1986 to 2001.

A rapid emergence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection (from 26.3% in 1986 to 77% in 2001) was found. The susceptibility of 200 nonduplicate blood isolates of MRSA and 100 MRSA isolates causing refractory bacteremia to 22 antimicrobial agents disclosed that glycopeptides, quinupristin-dalfopristin, and linezolid remained the most active agents.

Anti-Bacterial Agents↗
PubMed2004

Isolation of a chromosomal region of Klebsiella pneumoniae associated with allantoin metabolism and liver infection.

Klebsiella pneumoniae liver abscess with metastatic complications is an emerging infectious disease in Taiwan. To identify genes associated with liver infection, we used a DNA microarray to compare the transcriptional profiles of three strains causing liver abscess and three strains not associated with liver infection. There were 13 clones that showed higher RNA expression levels in the three liver infection strains, and 3 of these 13 clones contained a region that was absent in MGH 78578. Sequencing of the clones revealed the replacement of 149 bp of MGH 78578 with a 21,745-bp fragment in a liver infection strain, NTUH-K2044. This 21,745-bp fragment contained 19 open reading frames, 14 of which were proven to be associated with allantoin metabolism. The K2044 (DeltaallS) mutant showed a significant decrease of virulence in intragastric inoculation of BALB/c mice, and the prevalence of this chromosomal region was significantly higher in strains associated with liver abscess than in those that were not (19 or 32 versus 2 of 94; P = 0.0001 [chi(2) test]). Therefore, the 22-kb region may play a role in K. pneumoniae liver infection and serve as a marker for rapid identification.

Allantoin↗
PubMed2004

Patient data, early SARS epidemic, Taiwan.

Of the first 10 patients in the epidemic of severe acute respiratory syndrome (SARS) in Taiwan, 4 were closely associated with a SARS patient in an airplane. Loose stools or diarrhea, hemophagocytosis syndrome, and high serum levels of interleukin (IL)-6, IL-8, and tumor necrosis factor-a associated with lung lesions were found in all 10 patients.

Adult↗
PubMed2004

SARS in hospital emergency room.

Thirty-one cases of severe acute respiratory syndrome (SARS) occurred after exposure in the emergency room at the National Taiwan University Hospital. The index patient was linked to an outbreak at a nearby municipal hospital. Three clusters were identified over a 3-week period. The first cluster (5 patients) and the second cluster (14 patients) occurred among patients, family members, and nursing aids. The third cluster (12 patients) occurred exclusively among healthcare workers. Six healthcare workers had close contact with SARS patients. Six others, with different working patterns, indicated that they did not have contact with a SARS patient. Environmental surveys found 9 of 119 samples of inanimate objects to be positive for SARS coronavirus RNA. These observations indicate that although transmission by direct contact with known SARS patients was responsible for most cases, environmental contamination with the SARS coronavirus may have lead to infection among healthcare workers without documented contact with known hospitalized SARS patients.

Adult↗
PubMed2004

Clinical manifestations, laboratory findings, and treatment outcomes of SARS patients.

Clinical and laboratory data on severe acute respiratory syndrome (SARS), particularly on the temporal progression of abnormal laboratory findings, are limited. We conducted a prospective study on the clinical, radiologic, and hematologic findings of SARS patients with pneumonia, who were admitted to National Taiwan University Hospital from March 8 to June 15, 2003. Fever was the most frequent initial symptom, followed by cough, myalgia, dyspnea, and diarrhea. Twenty-four patients had various underlying diseases. Most patients had elevated C-reactive protein (CRP) levels and lymphopenia. Other common abnormal laboratory findings included leukopenia, thrombocytopenia, and elevated levels of aminotransferase, lactate dehydrogenase, and creatine kinase. These clinical and laboratory findings were exacerbated in most patients during the second week of disease. The overall case-fatality rate was 19.7%. By multivariate analysis, underlying disease and initial CRP level were predictive of death.

Adult↗
PubMed2004

Infection control and SARS transmission among healthcare workers, Taiwan.

This study found infrequent transmission of severe acute respiratory syndrome (SARS) coronavirus to healthcare workers involved in the care of the first five case-patients in Taiwan, despite a substantial number of unprotected exposures. Nonetheless, given that SARS has been highly transmissible on some occasions, we still recommend strict precautions.

Antibodies, Viral↗
PubMed2004

Detection of SARS-associated coronavirus in throat wash and saliva in early diagnosis.

The severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is thought to be transmitted primarily through dispersal of droplets, but little is known about the load of SARS-CoV in oral droplets. We examined oral specimens, including throat wash and saliva, and found large amounts of SARS-CoV RNA in both throat wash (9.58 x 10(2) to 5.93 x 10(6) copies/mL) and saliva (7.08 x 10(3) to 6.38 x 10(8) copies/mL) from all specimens of 17 consecutive probable SARS case-patients, supporting the possibility of transmission through oral droplets. Immunofluorescence study showed replication of SARS-CoV in the cells derived from throat wash, demonstrating the possibility of developing a convenient antigen detection assay. This finding, with the high detection rate a median of 4 days after disease onset and before the development of lung lesions in four patients, suggests that throat wash and saliva should be included in sample collection guidelines for SARS diagnosis.

Adult↗
PubMed2004

Molecular epidemiology and control of nosocomial methicillin-resistant Staphylococcus aureus infection in a teaching hospital.

BACKGROUND AND PURPOSE: Nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection is difficult to control. Due to a dramatic increase in the nosocomial MRSA infection rate at our hospital from 2000 to 2001, this study was conducted to identify the source of these infections and the effectiveness of control measures. METHODS: 179 healthcare workers (HCWs) were screened for carriage of MRSA. Starting in April 2001, all patients with MRSA infection or colonization were put in strict contact and cohort isolation. The bacterial isolates of HCW carriers and patients with MRSA infection from April 2001 to September 2001 were subjected to antimicrobial susceptibility testing by disk-diffusion method and molecular typing by pulsed-field gel electrophoresis (PFGE). RESULTS: Fifteen HCWs were found to be carriers of MRSA. They were all given topical mupirocin treatment. After these interventions, the nosocomial MRSA infection rate decreased from 1.23 to 0.53 per 1000 patient-days. All 61 MRSA isolates available for antimicrobial susceptibility testing and molecular typing were multidrug resistant. PFGE study revealed 2 predominant types, type C and type Y, comprising 36 and 12 isolates, respectively. CONCLUSIONS: The current study demonstrates the importance of measures to control nosocomial MRSA infections in hospitals that already have a high incidence of endemic MRSA infection. Elimination of carriage by healthcare workers, and strict contact and cohort isolation are the main effective measures.

Anti-Bacterial Agents↗
PubMed2004

Nosocomial infection of Aeromonas hydrophila presenting as necrotizing fasciitis.

Aeromonas hydrophila is infrequently reported as a causative organism of necrotizing fasciitis. We report a case of necrotizing fasciitis due to A. hydrophila in a 44-year-old man with Marfan syndrome who underwent valve replacement surgery twice. He was admitted due to a 2-day history of fever. The fever was attributed to hepatitis, and ingestion of herbal medication was suspected to be the cause. The fever relapsed on the 28th day of hospitalization with rapidly progressive erythematous patches on the bilateral lower extremities. Septic shock developed within a few hours, and 2 small diagnostic incisions on the skin lesions suggested necrotizing fasciitis. Surgical exploration further revealed extensive necrosis of the subcutaneous tissue and fascia, but the muscle was spared. Blood cultures and cultures of the debrided tissue all yielded A. hydrophila. Pathological examination showed necrosis and degeneration of the soft tissue. Although appropriately managed with broad-spectrum antibiotics, fasciotomies and debridement, the patient's condition deteriorated rapidly and resulted in death 11 hours after the surgery. This case indicates that A. hydrophila can be a causative organism of nosocomial necrotizing fasciitis.

Adult↗
PubMed2004

Discontinuation of secondary prophylaxis in AIDS patients with disseminated non-tuberculous mycobacteria infection.

From June 1994 to June 2002, disseminated infections due to non-tuberculous mycobacteria (NTM) were diagnosed in 42 of 716 (5.9%) non-haemophiliac HIV-infected patients aged > or =15 years who were treated at National Taiwan University Hospital. The median age of these patients was 35 years (range, 27 to 60 years). The median CD4+ cell count and plasma viral load at the time of diagnosis of disseminated NTM infections were 8 x 10(6)/L (range, 0 to 892 x 10(6)/L) and 37,600 copies/mL (range, <400 to >750,000 copies/mL), respectively. The nadir CD4+ count during the observation period was 6 x 10(6)/L (range, 0 to 30 x 10(6)/L). The species of NTM isolated included Mycobacterium avium complex (MAC) [n = 35], Mycobacterium kansasii (4), Mycobacterium chelonae (1), Mycobacterium abscessus (1), and unidentified NTM (3). Co-infection with 2 species of NTM was diagnosed in 2 patients. NTMs were isolated from blood (n = 18), liver (18), lymph node (12), bone marrow (10), cerebral spinal fluid (1), ascites (1), and pericardial effusion (1). The median duration of antimycobacterial therapy of the 42 patients was 7 months (range, 0 to 24 months). Mortality during the study period was greater in the patients enrolled before highly active antiretroviral therapy (HAART) was introduced (14 of 15, 93%) than in those who received HAART (9 of 27, 33%). As of December 31, 2002, 15 patients (35.7%) had discontinued secondary prophylaxis against disseminated NTM infections when their median CD4+ count had increased to 119 x 10(6)/L (range, 25 to 465 x 10(6)/L), and 86.7% (13/15) of the patients had achieved an undetectable plasma viral load after HAART. During the median observation duration of 12 months (range, 2 to 57 months), none of the 15 patients had relapse of disseminated NTM infections. Our findings indicate that disseminated NTM infections without primary prophylaxis were associated with a high mortality rate, especially before HAART became available. In patients who received HAART and had a favorable response with viral suppression and immune restoration, discontinuation of secondary prophylaxis against disseminated NTM infections was safe.

AIDS-Related Opportunistic Infections↗
PubMed2004

Simultaneous determination of indinavir, ritonavir and saquinavir in plasma by high-performance liquid chromatography.

BACKGROUND AND PURPOSE: Antiretroviral regimens consisting of a combination of protease inhibitors have been shown to be highly potent for the treatment of HIV infection. Therapeutic drug monitoring may ensure optimal drug levels to improve efficacy and minimize side effects. The purpose of this study was to establish a method for simultaneous determination of plasma concentrations of indinavir (IDV), ritonavir (RTV) and saquinavir (SQV) by high-performance liquid chromatography (HPLC) in a single run. METHODS: A C(18) column and an ultraviolet detector set at 215 nm were used in the HPLC. The mobile phase consisted of phosphate buffer (50 mM, pH 5.6) and acetonitrile (55:45, v/v), and the flow rate was 1.5 mL/min. Plasma sample (0.5 mL) containing IDV, RTV, and SQV was alkalinized with ammonia water (10%) and propylparaben added as an internal standard (IS), which was then extracted with methyl tert.-butyl ether. The organic layer was taken and evaporated to dryness. The residue was dissolved in the mobile phase, and the solution was washed with n-hexane followed by HPLC analysis. RESULTS: The calibration curves were linear for each of the 3 drugs in the studied concentration range (0.1 to 5 microg/mL). The extraction recoveries were greater than 90%. One HPLC run takes less than 15 minutes. Analysis of plasma samples of patients treated with combinations of these drugs demonstrated that the calibration curves covered the clinical concentration range. CONCLUSIONS: This study established a simple and accurate method for simultaneous determination of IDV, RTV, and SQV in plasma by isocratic HPLC. The method is practical for therapeutic drug monitoring.

Chromatography, High Pressure Liquid↗
PubMed2004

Changing characteristics of typhoid fever in Taiwan.

Typhoid fever, a systemic disease caused by Salmonella typhi, is classically characterized by fever and abdominal symptoms. Although now considered uncommon, it seems to have re-emerged in Taiwan in recent years. We conducted a retrospective study of the clinical characteristics and microbiologic findings in 24 confirmed cases of typhoid fever treated over a 7-year period at a medical center in northern Taiwan. There were 11 males and 13 females, including 15 adults (over 18 years in age) and 9 children. Their mean age was 24.7 years (range, 9 months to 58 years). Twelve patients had recently returned from abroad, mostly from Southeast Asia. The most common complaints were fever (24/24), diarrhea (18/24), abdominal pain (10/24), and cough (10/24). The average duration of fever before diagnosis was 14.1 days, with a maximum of 30 days. Relative bradycardia was noted in 6 patients. Leukopenia was noted in 2 patients. S. typhi was isolated from blood culture in 20 cases, from stool culture in 3 cases, and from bone marrow culture in 1 case. Widal test was only positive initially in 7/18 cases. Fever of unknown origin was the most common initial diagnosis. Typhoid or enteric fever was impressed initially in only 2 cases. Almost all isolates of S. typhi were susceptible to antibiotics currently used for typhoid fever, with only 1 isolate resistant to chloramphenicol. All patients survived after antibiotic treatment. Only 1 patient developed recurrence after a 10-day course of ceftriaxone. In conclusion, the diagnosis of typhoid fever is often challenging due to non-specific symptoms and lack of an immediate confirmatory test. It is important to include this disease in the differential diagnosis of febrile patients with abdominal symptoms.

Abdominal Pain↗
PubMed2004

Clinical features and outcome analysis of infective endocarditis in elderly patients.

BACKGROUND AND PURPOSE: Diagnosis and management of infective endocarditis (IE) in elderly patients remains a difficult problem. This study evaluated the clinical and microbiologic characteristics and outcome of IE in elderly patients. METHODS: From 1996 to 2002, clinical and microbiologic data from 67 patients with IE aged > or = 65 years at National Taiwan University Hospital were reviewed and analyzed. RESULTS: The median age of the 67 patients was 74 years (range, 66 to 95 years). Staphylococci and streptococci were the 2 leading etiologies of IE. Forty seven of the cases were defined as community-acquired. IE had not been diagnosed at admission in nearly two-thirds of cases. Of the 20 episodes of nosocomial IE, the median interval to development of IE after hospitalization was 30 days. Staphylococci constituted 90% of causative pathogens in nosocomial IE. The in-hospital mortality rate was 29.9%. Univariate analysis revealed that staphylococci as the causative pathogen and nosocomial IE were predictors of fatal outcome (p <0.05). When significant variables related to a fatal outcome on univariate analysis, i.e., staphylococcal IE, nosocomial IE, acute renal failure and cardiac complications, were entered in the multivariate analysis, acute renal failure and development of congestive heart failure or new conduction disturbance were both significantly associated with in-hospital death. CONCLUSIONS: Diagnosis of IE in the elderly was often delayed and a substantial proportion of patients died during hospitalization. Staphylococcal IE and nosocomial IE were significant predictors of in-hospital death.

Aged↗