Biomedical subjects

Yung-Ching Liu

Publications and source records attributed to Yung-Ching Liu.

At least 55 records · Page 3Linked to original sources

PubMed2004

Characteristics of a dengue hemorrhagic fever outbreak in 2001 in Kaohsiung.

A dengue outbreak occurred in Kaohsiung City starting in July in 2001. We studied the clinical profile of all patients admitted to Kaohsiung Veterans General Hospital during this outbreak from July 2001 to January 2002. A total of 25 cases of clinically suspected dengue fever were treated during this period, and 13 of them were confirmed by laboratory results (13/25; 52%). Eleven of the 25 patients (11/25; 44%) were admitted. The mean age of the patients with laboratory confirmation of infection was 53 years (range, 7 to 85 years). Headache (7/13; 53.8%), bone pain (8/13; 61.5%), myalgia (10/13; 76.9%), abdominal pain (7/13; 53.8%), and skin rash (9/13; 69.2%) were the most common presentations. A high proportion of patients were classified as having dengue hemorrhagic fever (DHF) [6/13; 46.2%] and 2 of these patients had dengue shock syndrome (DSS) based on the World Health Organization criteria. Pretibial petechia (6/13; 46.1%), gastrointestinal bleeding (6/13; 46.1%), and hemoptysis (4/13; 30.8%) were the most common hemorrhagic manifestations. The average hospital stay was 7.1 days. Thrombocytopenia was very common and 84.6% patients had a platelet count less than 100,000/mm3. Monocytosis was found in all patients. Few patients required blood or platelet concentrate transfusion. The 2 patients who developed DSS both survived. All patients recovered completely without any obvious sequela. In conclusion, there was a high percentage of DHF among patients in the dengue outbreak in 2001. Increasing rates of DHF compared to previous reports from Taiwan may be a sign of hyperendemicity (multiple serotypes present) of the dengue virus in Kaohsiung City and its greater likelihood elsewhere in Taiwan. Prevention and control of both dengue fever and DHF have thus become increasingly important.

Adolescent↗

PubMed2004

Emergence of G9 serotype rotavirus as a major cause of infectious gastroenteritis in southern Taiwan.

Infectious gastroenteritis is a common illness in children. This study investigated the etiology and clinical manifestations of hospitalized children with symptoms of infectious gastroenteritis in southern Taiwan. We studied 467 consecutive patients with infectious gastroenteritis aged from 2 days to 10 years hospitalized from April 2001 to March 2002. Rotavirus was the most common etiology (57%) of infectious gastroenteritis in these patients. Bacterial infection was noted in 57 cases (12%). Rotavirus was found in 92% of nosocomial infectious gastroenteritis (p < or = 0.001). Bloody stool was a presentation of bacterial infection in 74% of cases and rotavirus gastroenteritis in 8% of cases (p < or = 0.001). The G serotype of rotavirus was identified in 87 patients. Serotype G1 was the most common (51%), followed by G9 (31%). The emergence of serotype G9 strains in rotavirus infection has not been previously reported from Taiwan. Incorporation of G9 rotavirus into vaccines should be considered.

Child↗

PubMed2003

High levels of plasma dengue viral load during defervescence in patients with dengue hemorrhagic fever: implications for pathogenesis.

Studies of the pathogenesis of dengue hemorrhagic fever (DHF), a potentially life-threatening disease, have revealed the importance of initial high levels of virus replication. However, the possible involvement of virus during the transition from fever to defervescence, a critical stage in determining the severity of disease, has not been appreciated. Using quantitative reverse transcription-polymerase chain reaction, we examined the levels of plasma dengue viral load during both fever and defervescence periods in patients from a DEN-3 outbreak in southern Taiwan in 1998. Higher levels of plasma dengue viral RNA were found in DHF patients than in DF patients. During defervescence, while the level of plasma dengue viral RNA was undetectable in most DF patients, it remains high in all DHF patients. Using a modified immunoprecipitation assay, we demonstrated for the first time that the plasma dengue viruses persisting during defervescence were in the immune complexes for most DHF patients. These findings suggest that continued active viral replication or delay in the clearance of viremia contributes to the pathogenesis of DHF. Moreover, high levels of plasma dengue viral RNA during defervescence may serve as a disease marker for DHF.

Adult↗

PubMed2003

Rapid detection of pulmonary tuberculosis using the BDProbeTEC ET Mycobacterium tuberculosis Complex Direct Detection Assay (DTB).

The ability to rapidly detect tubercle bacilli in respiratory secretions was determined for the BDProbeTEC ET Mycobacterium tuberculosis Complex Direct Detection Assay in comparison with the acid-fast smear (AFS). A total of 267 respiratory specimens obtained from 89 patients were evaluated. The DTB assay was positive in 70 of 78 culture positive specimens (89.7%) and 12 of 177 culture negative specimens (6.8%). The AFS was positive in 33 of 78 culture positive specimens (42.3%) and 3 of 186 culture negative specimens (1.6%). The sensitivity, specificity, positive predictive value, and negative predictive value of DTB assay were 89.7%, 93.7%, 85.4%, and 95.7%, respectively. The sensitivity of a single DBT (74.4%) was 2.1-times greater than three AFS (35.9%). The greater cost of the DTB assay compared to the AFS was compensated by its valuable information for the diagnosis and control of tuberculosis. These results demonstrated the clinical usefulness of the DTB assay for the rapid diagnosis of tuberculosis in respiratory specimens.

Bacteriological Techniques↗

PubMed2003

Correlation between pyrazinamide activity and pncA mutations in Mycobacterium tuberculosis isolates in Taiwan.

A total of 76 clinical Mycobacterium tuberculosis isolates from Taiwan were tested for pyrazinamidase activity, pyrazinamide susceptibility, and pncA mutations. Frequency of resistance to PZA rose with increases in resistance to first-line drugs. Of 17 pyrazinamide-resistant strains, 7 (3 of which had not been previously described) possessed mutations in the pncA gene.

Amidohydrolases↗

PubMed2003

Telithromycin- and fluoroquinolone-resistant Streptococcus pneumoniae in Taiwan with high prevalence of resistance to macrolides and beta-lactams: SMART program 2001 data.

There is a high prevalence of beta-lactam- and macrolide-resistant Streptococcus pneumoniae in Taiwan. To understand the in vitro susceptibilities of recent isolates of S. pneumoniae to fluoroquinolones and telithromycin (which is not available in Taiwan), the MICs of 23 antimicrobial agents for 936 clinical isolates of S. pneumoniae isolated from different parts of Taiwan from 2000 to 2001 were determined by the agar dilution method. Overall, 72% of isolates were not susceptible to penicillin (with 61% being intermediate and 11% being resistant) and 92% were resistant to erythromycin. Telithromycin MICs were >or=1 microg/ml for 16% of the isolates, and for 99% of these isolates the MICs of all macrolides tested were >or=256 microg/ml; all of these isolates had the constitutive macrolide-lincosamide-streptogramin B phenotype. Eighty-eight percent of the isolates were resistant to three or more classes of drugs. The ciprofloxacin MICs were >or=4 microg/ml for six (0.6%) isolates from five patients collected in 2000 and 2001, and the levofloxacin MICs were >or=8 microg/ml for five of these isolates. Seven isolates for which ciprofloxacin MICs were >or=4 microg/ml, including one isolate recovered in 1999, belonged to three serotypes (serotype 19F, five isolates; serotype 23A, one isolate; and serotype 23B, one isolate). The isolates from the six patients for which ciprofloxacin MICs were >or=4 microg/ml had different pulsed-field gel electrophoresis profiles and random amplified polymorphic DNA patterns, indicating that no clonal dissemination occurred over this time period. Despite the increased rate of fluoroquinolone use, the proportion of pneumococcal isolates for which ciprofloxacin MICs were elevated (>or=4 microg/ml) remained low. However, the occurrence of telithromycin resistance is impressive and raises concerns for the future.

Adult↗

PubMed2003

Telithromycin and quinupristin-dalfopristin resistance in clinical isolates of Streptococcus pyogenes: SMART Program 2001 Data.

This study evaluated the current status of antimicrobial resistance in clinical isolates of Streptococcus pyogenes in Taiwan as part of the SMART (Surveillance from Multicenter Antimicrobial Resistance in Taiwan) program. In 2001, 419 different isolates of S. pyogenes, including 275 from respiratory secretions, 87 from wound pus, and 31 from blood, were collected from nine hospitals in different parts of Taiwan. MICs of 23 antimicrobial agents were determined at a central location by the agar dilution method. All of the isolates were susceptible to penicillin (MIC at which 90% of the isolates were inhibited [MIC(90)], moxifloxacin > ciprofloxacin = levofloxacin = gatifloxacin > gemifloxacin) demonstrated potent activity against nearly all of the isolates of S. pyogenes tested. Thirty-two isolates (8%) were not susceptible to quinupristin-dalfopristin. Seventeen percent of isolates had telithromycin MICs of >or=1 microg/ml, and all of these isolates exhibited erythromycin MICs of >or=32 microg/ml. The high prevalence of resistance to telithromycin (which is not available in Taiwan) limits its potential use in the treatment of S. pyogenes infections, particularly in areas with high rates of macrolide resistance.

Anti-Bacterial Agents↗

PubMed2003

Eosinophilic meningitis caused by Angiostrongylus cantonensis associated with eating raw snails: correlation of brain magnetic resonance imaging scans with clinical findings.

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis worldwide. Human infection occurs after ingestion of the worms in raw snails or fish that serve as intermediate hosts. Two outbreaks of central nervous system infection with A. cantonensis occurred in Kaoshiung, Taiwan, during 1998 and 1999 among Thai laborers who ate raw snails. A detailed clinical studies of 17 of these patients was conducted, including study of 13 patients who underwent magnetic resonance imaging (MRI) scans of the brain. The MRI scans revealed high signal intensities over the globus pallidus and cerebral peduncle on T1-weighted imaging, leptomeningeal enhancement, ventriculomegaly, and punctate areas of abnormal enhancement within the cerebral and cerebellar hemisphere on gadolinium-enhancing T1 imaging, and a hyperintense signal on T2-weighted images. There was a significant correlation between severity of headache, cerebrospinal fluid (CSF) pleocytosis, and CSF and blood eosinophilia with MRI signal intensity in T1-weighted imaging (P < 0.05). Eosinophilic meningitis produced by A. cantonensis needs to added to the list of causes of hyperintense basal ganglia lesions found on T1-weighted MRI scans in tropical countries.

Adult↗

PubMed2003

Liver abscess caused by an infected ventriculoperitoneal shunt.

Pyogenic liver abscess in Taiwan is most commonly due to Klebsiella pneumoniae infection in diabetic patients, and less frequently due to biliary tract infections. Liver abscess caused by ventriculoperitoneal (VP) shunt is very rare. We report a case of liver abscess caused by methicillin-resistant Staphylococcus aureus (MRSA), which developed as a complication of an infected VP shunt. A 53-year-old woman, who had shad a VP shunt implanted 3 months previously for hydrocephalus due to intracranial hemorrhage, presented with fever off and on, drowsiness and seizure attacks for 1 week. Computed tomography (CT) of the brain showed only mild right-sided hydrocephalus, and was negative for intracranial hemorrhage and intracranial mass. Analysis of cerebrospinal fluid showed significant pleocytosis and hypoglycorrhachia. CT scan of the abdomen disclosed a huge abscess in the right lobe of the liver. Cultures of both the cerebrospinal fluid and aspirated liver abscess isolated MRSA. The patient was treated with intraventricular and intravenous vancomycin, intravenous teicoplanin and oral rifampicin, followed by oral chloramphenicol and rifampicin. Percutaneous drainage of the liver abscess and externalization of the VP shunt were performed. The liver abscess had resolved almost completely on ultrasonography after 2 weeks of therapy. Liver abscess in patients with a VP shunt should be considered a possible abdominal complication of the VP shunt, and may be caused by unusual pathogens. Diagnosis requires CT scan and direct aspiration and culture of the liver abscess. Treatment requires management of both the liver abscess and the infected shunt.

Female↗

PubMed2003

Microscopic morphology in smears prepared from MGIT broth medium for rapid presumptive identification of Mycobacterium tuberculosis complex, Mycobacterium avium complex and Mycobacterium kansasii.

Mycobacterium species has a specific morphology when grown in liquid medium. Mycobacterium tuberculosis complex (MTB) often exhibits serpentine cording, which is different from the dot and cross-barring morphology observed in Mycobacterium avium complex (MAC) and Mycobacterium kansasii (MK), respectively. These characteristic morphologies can be used as a cost-effective method for rapid, presumptive identification of mycobacterial isolates cultured from the MGIT 960 system. By using Kinyoun acid-fast stain, serpentine cording was found in 840 of 904 (92.1%) samples positive for MTB; dot or loose aggregation was observed in 112 of 136 (82.3%) samples positive for MAC; and the cross-barring, ladder-like, morphology was observed in 45 of 56 (80.5%) samples positive for MK. The sensitivity and specificity were 92.9% and 96.4% for MTB; 82.4% and 94.5% for MAC; and 80.4% and 94.6% for MK, respectively. Using growth rate selection to exclude rapid growers, the positive and negative predictive values were 98% and 87.6% for MTB; 78.3% and 98% for MAC; and 78.9% and 99.1% for MK, respectively. Twenty-eight (93.3%) of 30 strains with ball morphology were rapid growers. Microscopic morphology can be used for rapid, presumptive identification of M. tuberculosis complex, M. kansasii, and M. avium complex and act as a guide for appropriate selection of initial probes to reduce costs.

Culture Media↗

PubMed2003

Outbreak of aseptic meningitis among adults in southern Taiwan.

A total of 38 adult cases of aseptic meningitis were diagnosed based on clinical manifestations as well as examination of cerebrospinal fluid at Kaohsiung Veterans General Hospital in 2001. The majority (31 cases, 82%) of cases occurred between June and August, and most (33 cases, 87%) of them aged from 18 to 35 years (median age, 25 years). The male-to-female ratio was 2.16:1. Common clinical presentations included headache, fever, nausea or vomiting, and symptoms of common cold. On initial cerebrospinal fluid examination, white cell counts were above 500 cells/mm3 in 7 (18%) cases, and neutrophils predominated in 10 (28%) of 36 cases. The cerebrospinal fluid protein concentration was below 100 mg/dL in 29 (77%) of 38 cases, and hypoglycorrhachia (cerebrospinal fluid/serum glucose ratio <0.5) was seen in 9 (24%) cases. Enterovirus as a definite etiology was confirmed by isolation from cerebrospinal fluid in 17 (45%) of 38 cases and was the presumptive etiology by isolation from the stool or throat swab in 2 (5%) cases. Of the 19 cases with positive viral isolation, echovirus serotype 30 accounted for the majority (15 cases, 79%), followed by echovirus serotype 6 (3 cases, 16%), with one (5%) case undetermined. The viral isolation rate from cerebrospinal fluid correlated to the day of cerebrospinal fluid sampling after disease onset (chi2 = 12.05, p = 0.007). All patients were discharged uneventfully without receiving antibiotic therapy.

Adolescent↗

PubMed2003

Mycobacteriosis in patients with fever of unknown origin.

Fever of unknown origin (FUO) is a common syndrome. A total of 94 patients (57 men and 37 women; mean age, 56.3 +/- 19 years, range, 18-86 years) who met the criteria of FUO were included in this study. Mycobacteriosis was diagnosed in 22 (23%) of these patients (13 men and 9 women), including 9 with disseminated disease and 13 with pulmonary disease. There was no significant statistical difference in age, sex, short-term survival status (3 months), and other clinical parameters between patients with and without mycobacteriosis. Clinical manifestations may be specific or nonspecific. The most common initial presentations in patients with mycobacteriosis were respiratory tract symptoms, mainly of cough and dyspnea, observed in 11 (50%) patients, and disturbance of consciousness in 6 (27%). The associated conditions included malnutrition (4 patients, 18%), diabetes mellitus (3, 14%), and renal failure (3, 14%). Four (18%) patients had a history of pulmonary tuberculosis or tuberculous spondylitis in their early adulthood. The 2 most common findings on chest radiograph were interstitial (41%) and nonspecific infiltrative (32%) patterns. In conclusion, mycobacteriosis remains the leading cause of FUO in southern Taiwan and it is important to screen for this treatable disease in all cases of FUO.

Adolescent↗

PubMed2002

Clinical manifestations of strongyloidiasis in southern Taiwan.

The diagnosis and management of strongyloidiasis present a continuous challenge in developing countries including Taiwan. In this study, the clinical characteristics and microbiological findings of 27 patients with Strongyloides stercoralis infection were retrospectively analyzed. Intestinal infection was identified in 17 patients and hyperinfection syndrome or disseminated disease in 10 (including 2 autopsy cases). The most frequent clinical findings were diarrhea (74%), fever (70%), abdominal pain (59%), cough (37%), dyspnea (33%), and constipation (26%). The common initial laboratory abnormalities were leukocytosis (81%), anemia (67%), liver function impairment (52%), and eosinophilia (44%). Most of the 27 patients had comorbid conditions, including malnutrition in 20 (74%), corticosteroid dependence in 15 (55%), chronic obstructive pulmonary disease in 9 (33%), chronic liver disease or cirrhosis in 8 (30%), and peptic ulcer disease in 7 (26%). There was no difference in the time interval from symptom onset to diagnosis between the intestinal infection group and the hyperinfection/disseminated group (22 +/- 15 vs 17 +/- 9 days). Larvae of S. stercoralis were identified in the stool of 24 patients, in the sputum smear of 5, in the gastric biopsy of one, and on histology of autopsy specimens in 2. Twenty-six patients received antiparasitic drug therapy of variable duration (mebendazole in 24, albendazole in 2, combined therapy in one). The overall cure rate was 52% (14/27). Relapse occurred in 4 patients. The overall mortality was 26% (7/27). There was a high mortality (up to 50%) in the hyperinfection/disseminated disease group. In conclusion, diagnosis of strongyloidiasis is often delayed and overlooked because of nonspecific symptoms. Physicians in endemic regions should include strongyloidiasis in the differential diagnosis when patients present with gastrointestinal and/or pulmonary symptoms with peripheral eosinophilia.

Adolescent↗

PubMed2002

Antimicrobial susceptibility testing of Mycobacterium tuberculosis to first-line drugs: comparisons of the MGIT 960 and BACTEC 460 systems.

The reliability of the Mycobacteria Growth Indicator Tube (MGIT) 960 system for rapid antimicrobial susceptibility testing (AST) of Mycobacterium tuberculosis was evaluated. Forty-seven isolates, including 10 fully susceptible and 37 resistant strains, were tested for susceptibility to the critical concentrations of streptomycin (STR), isoniazid (INH), rifampin (RMP), and ethambutol (EMB), as recommended by the manufacturer. Strains resistant to the critical concentrations were tested with higher concentrations. The results were compared to those obtained by a radiometric method (BACTEC 460TB) and by a conventional agar dilution method, which served as the reference method. Based on these data, we suggest that the following antibiotic concentrations give satisfactory results with the MGIT 960 system: STR, 4.0 microg/ml; INH, 0.1 microg/ml; RMP, 1.0 microg/ml; and EMB, 5.0 microg/ml. The time required to obtain susceptibility results averaged 6.9 days by the MGIT 960 system and 5.4 days by the BACTEC 460TB system; these intervals were not significantly different. This study shows that the MGIT 960 system is a reliable, rapid, automated method for testing the susceptibility of M. tuberculosis isolates to first-line drugs.

Antitubercular Agents↗

PubMed2002

Endocarditis caused by penicillin-resistant Streptococcus mitis in a 12-year-old boy.

A case of congenital coronary arteriovenous fistula with infective endocarditis caused by penicillin-resistant Streptococcus mitis is reported. Lack of prophylactic antibiotics during dental procedure may cause the development of endocarditis. Bactericidal test (Schlichter test) was performed to guide the therapy for this case of bacterial endocarditis caused by penicillin-resistant viridans streptococci. This case highlights the importance of antibiotic prophylaxis in patients with underlying heart disease undergoing dental procedures.

Ampicillin↗

PubMed2002

Excessive use of antibiotics in the community associated with delayed admission and masked diagnosis of infectious diseases.

Resistance to antimicrobial drugs is becoming more serious throughout the world, and is a major problem in Taiwan. The selective pressure of antibiotic use makes some degree of antibiotic resistance inevitable, but extraordinarily high rates of resistance suggest excessive use. This report reviews collaborative studies undertaken in the southern city of Kaohsiung to better define the use of antibiotics in the community and to determine whether recent use of antibiotics results in delayed admission and missed or masked diagnoses of infectious diseases among patients presented at an emergency department. Because of the unreliability in the patients' medical history, antibiotic activity was determined in the urine. These studies demonstrated that (1) detection of antibiotics in the urine offers a simple and inexpensive means to determine antibiotic use when a history of drug use is unreliable; (2) the high frequency of antibiotics use among patients presenting at emergency departments, clinics, and in the community may account for the extraordinarily high rates of antimicrobial drug resistance in Taiwan; and (3) recent use of antimicrobial drugs before visiting an emergency department was associated with a significantly increased risk of delayed and masked or missed diagnoses of infectious diseases, and missed diagnosis of noninfectious diseases. These findings reflect inherent social, economic, and cultural problems and constraints in the medical care system in Taiwan. The issue of inappropriate use of antibiotics in the community, hospitals, and agriculture is now being addressed at a national level.

Adult↗

PubMed2002

Safety and efficacy of cefepime versus ceftazidime in the treatment of severe infections.

An open-label, randomized study was conducted to evaluate the safety and efficacy of cefepime versus ceftazidime in the treatment of severe bacterial infections, including septicemia, urinary tract infection, bacterial bronchitis, bacterial pneumonia, and intraabdominal infection. Fifty-two patients with severe infections were eligible and prospectively randomized to receive cefepime (26 patients) or ceftazidime (26 patients) during a 15-month period. Forty-two patients were evaluable (24 in the cefepime group and 18 in the ceftazidime group). Most (86%) of the patients had urinary tract infections and the most commonly isolated pathogen was Escherichia coli (79%). Satisfactory clinical response rates of 71% and 61%, and bacteriological eradication rates of 87.5% and 89% were achieved for the cefepime and ceftazidime groups, respectively. Two patients treated with cefepime died, one from superinfection and one from suspected paraneoplastic syndrome. Cultures of the blood obtained at entry into the study were positive in 19 (45%) of the 42 evaluable cases. In the cefepime group, a patient with Salmonella paratyphi A septicemia was cured, which has not been previously reported. Adverse effects attributable to therapy were minimal in both groups of patients, and none required discontinuation or dose reduction. In conclusion, these results suggest that cefepime is as efficacious and well tolerated as ceftazidime in the treatment of severe bacterial infections, such as septicemia, urinary tract infection, bacterial bronchitis, bacterial pneumonia, and intraabdominal infection.

Adolescent↗

PubMed2002

A pilot study of oral fleroxacin once daily compared with conventional therapy in patients with pyogenic liver abscess.

The object of this open-label, randomized, comparative study was to evaluate the efficacy and safety of fleroxacin versus conventional therapy (cefazolin plus gentamicin/cephalexin) in the treatment of patients with bacterial liver abscess. Thirty-one adult patients (26 men and 5 women) received fleroxacin 400 mg orally once daily for 3 weeks, and 30 adult patients (21 men and 9 women) received conventional therapy for 3 to 4 weeks. Patients was assessed on day 3 of treatment, thereafter every week during treatment, and at 7 to 14 days (compulsory follow-up) after treatment for assessment of bacteriologic, clinical, and safety parameters. A total of 20 patients in the fleroxacin group and 22 patients in the conventional therapy group were evaluated. Klebsiella pneumoniae was the predominant pathogen isolated in all evaluable cases. Bacteriologic cure was achieved in 14 (70%) of 20 patients on fleroxacin therapy compared with 18 (81.8%) of 22 patients on conventional therapy (p=0.48). Clinical cure was achieved in 12 (60%) and 18 (81.8%) patients, and improvement in 2 (10%) and 1 (4.5%) patients in the fleroxacin and conventional therapy group, respectively. Most of adverse effects were of mild intensity. Oral fleroxacin once-daily administration is an effective, alternative treatment of bacterial liver abscess.

Administration, Oral↗