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Cheng-Hsun Chiu

Publications and source records attributed to Cheng-Hsun Chiu.

At least 55 records · Page 3Linked to original sources
PubMed2004

Macrolide resistance and genotypic characterization of Streptococcus pneumoniae in Asian countries: a study of the Asian Network for Surveillance of Resistant Pathogens (ANSORP).

OBJECTIVES: To characterize mechanisms of macrolide resistance among Streptococcus pneumoniae from 10 Asian countries during 1998-2001. METHODS: Phenotypic and genotypic characterization of the isolates and their resistance mechanisms. RESULTS: Of 555 isolates studied, 216 (38.9%) were susceptible, 10 (1.8%) were intermediate and 329 (59.3%) were resistant to erythromycin. Vietnam had the highest prevalence of erythromycin resistance (88.3%), followed by Taiwan (87.2%), Korea (85.1%), Hong Kong (76.5%) and China (75.6%). Ribosomal methylation encoded by erm(B) was the most common mechanism of erythromycin resistance in China, Taiwan, Sri Lanka and Korea. In Hong Kong, Singapore, Thailand and Malaysia, efflux encoded by mef(A) was the more common in erythromycin-resistant isolates. In most Asian countries except Hong Kong, Malaysia and Singapore, erm(B) was found in >50% of pneumococcal isolates either alone or in combination with mef(A). The level of erythromycin resistance among pneumococcal isolates in most Asian countries except Thailand and India was very high with MIC(90)s of >128 mg/L. Molecular epidemiological studies suggest the horizontal transfer of the erm(B) gene and clonal dissemination of resistant strains in the Asian region. CONCLUSION: Data confirm that macrolide resistance in pneumococci is a serious problem in many Asian countries.

Alleles↗
PubMed2004

Fluoroquinolone resistance in clinical isolates of Streptococcus pneumoniae from Asian countries: ANSORP study.

Seventeen clinical isolates of Streptococcus pneumoniae showing reduced susceptibility to ciprofloxacin (MIC >/= 4 micro g/ml) collected from eight different Asian countries were analyzed by antimicrobial susceptibility, serotyping, pulsed-field gel electrophoresis (PFGE), and DNA sequencing of the quinolone resistance-determining regions (QRDRs) in gyrA, gyrB, parC, and parE. All isolates but one showed more than one amino acid alteration in QRDRs of four responsible genes. Ile460 --> Val in parE was the most common mutation. Data suggest that Lys137 --> Asn in parC may be a primary step in the development of high-level and multiple FQ resistance. An additional mutation of Ser81 --> Phe in gyrA resulted in high-level resistance to ciprofloxacin, levofloxacin, and gatifloxacin, whereas Ser79 --> Phe in parC may exert an important role in the development of moxifloxacin resistance. Two novel amino acid changes in gyrB, Ala390 --> Val and Asn423 --> Thr, were found. Data from PFGE suggest an introduction and local spread of multiple resistant Spain(23F)-1 clone in Hong Kong, but isolates from other Asian countries were not related to this clone.

Anti-Bacterial Agents↗
PubMed2004

High prevalence of antimicrobial resistance among clinical Streptococcus pneumoniae isolates in Asia (an ANSORP study).

A total of 685 clinical Streptococcus pneumoniae isolates from patients with pneumococcal diseases were collected from 14 centers in 11 Asian countries from January 2000 to June 2001. The in vitro susceptibilities of the isolates to 14 antimicrobial agents were determined by the broth microdilution test. Among the isolates tested, 483 (52.4%) were not susceptible to penicillin, 23% were intermediate, and 29.4% were penicillin resistant (MICs >/= 2 mg/liter). Isolates from Vietnam showed the highest prevalence of penicillin resistance (71.4%), followed by those from Korea (54.8%), Hong Kong (43.2%), and Taiwan (38.6%). The penicillin MICs at which 90% of isolates are inhibited (MIC(90)s) were 4 mg/liter among isolates from Vietnam, Hong Kong, Korea, and Taiwan. The prevalence of erythromycin resistance was also very high in Vietnam (92.1%), Taiwan (86%), Korea (80.6%), Hong Kong (76.8%), and China (73.9%). The MIC(90)s of erythromycin were >32 mg/liter among isolates from Korea, Vietnam, China, Taiwan, Singapore, Malaysia, and Hong Kong. Isolates from Hong Kong showed the highest rate of ciprofloxacin resistance (11.8%), followed by isolates from Sri Lanka (9.5%), the Philippines (9.1%), and Korea (6.5%). Multilocus sequence typing showed that the spread of the Taiwan(19F) clone and the Spain(23F) clone could be one of the major reasons for the rapid increases in antimicrobial resistance among S. pneumoniae isolates in Asia. Data from the multinational surveillance study clearly documented distinctive increases in the prevalence rates and the levels of antimicrobial resistance among S. pneumoniae isolates in many Asian countries, which are among the highest in the world published to date.

Anti-Infective Agents↗
PubMed2004

Salmonella enterica serotype Choleraesuis: epidemiology, pathogenesis, clinical disease, and treatment.

Nontyphoid Salmonella strains are important causes of reportable food-borne infection. Among more than 2,000 serotypes, Salmonella enterica serotype Choleraesuis shows the highest predilection to cause systemic infections in humans. The most feared complication of serotype Cholearesuis bacteremia in adults is the development of mycotic aneurysm, which previously was almost uniformally fatal. The advances in diagnostic techniques, surgical care, and antimicrobial therapy have greatly improved the survival of these patients. However, the recent emergence of serotype Choleraesuis that is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, and, notably, fluoroquinolone antibiotics has aroused concern about the use of these agents for the empirical treatment of systemic infection caused by this organism. In view of the serious implications of the situation, the chain of transmission and mechanism of resistance should be carefully studied to reduce the spread of infection and threat to human health. To date, there are no vaccines available to prevent serotype Choleraesuis infections in humans. The availability, in the near future, of the genome sequence of serotype Cholearesuis will facilitate the development of effective vaccines as well as the discovery of new targets for novel antimicrobial agents.

Anti-Bacterial Agents↗
PubMed2004

Prevalence and antimicrobial susceptibility of serogroup D nontyphoidal Salmonella in a university hospital in Taiwan.

The incidence of serogroup D Salmonella has been increasing in Taiwan. Most of these isolates belonged to Salmonella enterica serovar Enteritidis and showed a relatively higher rate of resistance to sulfamethoxazole-trimethoprim than to other antimicrobial agents. The results of molecular experiments indicated that genes responsible for the resistance were located on plasmids. The resistance may occur via horizontal gene transfer. Furthermore, the first identification of ciprofloxacin and ceftriaxone resistance in serogroup D Salmonella in our hospital is also than they did to other antimicrobial agents cause for concern.

Drug Resistance, Bacterial↗
PubMed2004

Clinical and microbiological analysis of bloodstream infections caused by Chryseobacterium meningosepticum in nonneonatal patients.

Chryseobacterium meningosepticum bloodstream infections in 11 nonneonatal patients were reported. More than half of the infections were community acquired. PCR assays indicated that the organisms produced extended-spectrum beta-lactamases as well as metallo-beta-lactamases. Genotyping showed diverse fingerprints among the isolates. Six patients survived without appropriate antibiotic treatment. Host factors are the major determinant of the outcomes of C. meningosepticum infections.

Adult↗
PubMed2004

Pulse methylprednisolone therapy in the treatment of immune globulin-resistant Kawasaki disease: case report and review of the literature.

A subgroup of patients with Kawasaki disease (KD) did not respond to intravenous immune globulin (IVIG) therapy. Corticosteroid therapy remains a controversial alternative in such cases. We report two young children with KD who failed to respond to three courses of IVIG therapy and subsequently received pulse methylprednisolone as an alternative. One had a satisfactory outcome but the other developed giant coronary aneurysms and had a myocardial infarction 2 months after onset of the illness. A review of relevant literature showed that the timing of initiation of pulse methylprednisolone therapy is important. It is suggested that pulse methylprednisolone therapy should be considered if there is no response to two standard doses of IVIG treatment.

Child, Preschool↗
PubMed2004

Prognostic implications of myoclonic jerk in children with enterovirus infection.

To determine the prognostic value of myoclonic jerk in children with enterovirus 71 (EV71) infection, a retrospective study was conducted on 665 enterovirus culture-confirmed patients admitted to Chang Gung Children's Hospital from January 2000 to September 2001. The mean age was 35.0 months +/- 32.2 months, ranging from 1 day to 15 years and 416 (62.6%) of them were male. Among these patients, 140 (21.1%) had EV71 isolated, and 150 (22.6%) had myoclonic jerk. Fifty one percent (72/140) of EV71 cases and only 15% (78/525) of non-EV71 cases had myoclonic jerk (p<0.001). The age of enterovirus patients with myoclonic jerk was younger than that of patients without myoclonic jerk (23.2 +/- 17.6 vs 38.4 +/- 34.6 months, p=0.005). The hospitalization and fever durations were significantly longer in the EV71 group than in the non-EV71 group (8.3 +/- 13 vs 4.2 +/- 2.7 days, p<0.001; 5.9 +/- 4.8 vs 4.2 +/- 3.0 days, p=0.009, respectively). Patients with myoclonic jerk also had higher percentages of severe illness, and neurologic sequelae (20% and 9%, respectively) than those without myoclonic jerk (5% and 1%, respectively) [p<0.001]. The positive predictive values of myoclonic jerk for EV71 infection, severe cases, and neurologic sequelae were 0.48, 0.20, and 0.09, respectively; the negative predictive values for severe cases and neurologic sequelae were 0.95 and 0.99, respectively. This study demonstrated that myoclonic jerk and EV71 infection are both independently associated with more severe disease and higher incidence of neurologic sequelae.

Adolescent↗
PubMed2004

Salmonella enterica serotype Choleraesuis infection in a medical center in northern Taiwan.

This retrospective study was conducted in order to determine the clinical and microbiologic features of infection with Salmonella enterica serotype Choleraesuis. Between March 1999 and December 2002, 55 patients with 66 isolates were enrolled for analysis. The ratio of males to females was 2.2:1. Most patients were older than 60 years (56%) and had underlying diseases (78%), such as diabetes mellitus, malignancy, and peptic ulcer. Fever (85%) was the most common clinical manifestation, followed by abdominal pain/fullness (31%). The gastrointestinal manifestations, including nausea/vomiting or diarrhea, accounted for only 13% and 11% of patients, respectively. S. enterica serotype Choleraesuis was extremely invasive, with a high predilection to cause bacteremia (78% of the isolates were from blood). Various types of metastatic focal infections were found, including infected arterial aneurysm, osteomyelitis, septic arthritis, urinary tract infection and wound infection. The crude mortality rate was 18% (10 deaths in 55 cases). Nearly all isolates were susceptible to the third-generation cephalosporins. A higher resistance rate to commonly used antimicrobial agents was found with ampicillin (85%, 56/66), trimethoprim-sulfamethoxazole (81%, 40/49), chloramphenicol (96%, 47/49), and ciprofloxacin (49%, 30/61). In view of the emergence of fluoroquinolone resistance, the third-generation cephalosporins appear to be the best choice for treatment of invasive infections caused by this organism.

Adult↗
PubMed2004

Comparison of multiplex polymerase chain reaction, culture, and serology for the diagnosis of Bordetella pertussis infection.

BACKGROUND: Accurate diagnosis of Bordetella pertussis infection is difficult. Polymerase chain reaction (PCR) tests are more sensitive than culture, but the reported sensitivity is variable. We prospectively compared the performance of culture, serology, and a multiplex PCR for the detection of B. pertussis. METHODS: A total of 193 paired nasopharyngeal (NP) swab specimens were examined by both culture and a multiplex PCR. Serology results were available in 103 patients. Medical charts of the patients with discrepant laboratory findings were reviewed and compared with the United States Centers for Disease Control and Prevention (CDC) clinical case definition. RESULTS: Of the 193 specimens, 11 were positive on both culture and PCR, and 14 were positive on PCR only. Of the 103 specimens with serology results, 3 were positive with all three methods, and 69 were negative with all methods. Eleven of the 14 PCR-positive only cases and 6 of the 19 serology-positive only cases were defined as true pertussis cases according to an expanded standard which includes either (1) culture positive or (2) PCR or serology positive with clinical features fulfilling the CDC clinical case definition and the patients having received macrolides treatment for more than 10 days. The sensitivity and specificity of the multiplex PCR were 79% and 98%, respectively, while those for serology were 47% and 85%, and for culture 39% and 100%. CONCLUSIONS: Our data confirm the superior sensitivity of the multiplex PCR in detection of B. pertussis, compared with conventional culture and serology. Clinical validation indicates that the multiplex PCR offers specific detection of B. pertussis from NP specimens.

Adolescent↗
PubMed2004

Bordetella pertussis infection in northern Taiwan, 1997-2001.

The clinical presentations of laboratory-confirmed Bordetella pertussis infection in Chang Gung Children's Hospital during 1997 and 2001 were analyzed. Of the 46 cases, 25 (54.3%) were male. The patients ages ranged from 24 days to 37 years, with a mean and median of 4.3 years and 10.5 years, respectively. Forty four patients had vaccination records, among them 23 patients (52.2%) had received > or = 3 doses of pertussis vaccine. Of the patients who were partially vaccinated (received 1 or 2 doses vaccine) or unvaccinated, 16 (69.6%) presented with whooping cough, 5 (22.2%) with post-tussive vomiting, and 13 (59.1%) with cyanosis. Leukocytosis (white blood cells > or = 15,000 cells/microL) and lymphocytosis (lymphocytes > or = 10,000 cells/microL) were observed in 17 (47.2%) and 16 (44.4%) of the patients, respectively. Fourteen patients (30.4%) developed complications, among which pneumonia was the most common (92.3%). Among infants < or = 1 year of age, 95.2% were partially vaccinated (20/21), compared with 5% (1/20) of the patients > 1 year of age (p<0.05). The overall complication rate was 37.5%, compared with 18.2% for patients > 1 year of age (p<0.05). One 2-month-old patient required ventilatory support after the development of cardiopulmonary failure. There was no mortality in this study. In summary, pertussis most commonly occurred in infants who were unvaccinated or partially vaccinated. These patients usually presented with atypical symptoms such as cyanosis or apnea. The importance of vaccination still cannot be overemphasized because immunized patients usually present with milder disease than those who are not immunized.

Adolescent↗
PubMed2003

Translocation of coagulase-negative bacterial staphylococci in rats following intestinal ischemia-reperfusion injury.

Many patients with sepsis have bacteremia for which no septic focus is identified either clinically or by autopsy. This study was designed to determine the relationship between the ischemia-reperfusion injury (IRI) and bacterial translocation that might be involved in the pathogenesis of necrotizing enterocolitis. In the first experiment, a total of 32 Sprague-Dawley rats weighing 150-200 g were divided into four groups. The mesentery to isolated loop was occluded for 30, 60, and 90 min following 30-min reperfusion in the three groups of experimental animals with a micro-bulldog clamp. A control group involved the same technique and exposure, without occlusion of the mesentery. Two sets of blood culture were taken through a catheter in the portal vein immediately and 15 min after the reperfusion, respectively. In another experiment, bacteria isolated were fed in different doses to control rats and those after 30- or 60-min ischemia and 30-min reperfusion. Two sets of blood culture were taken following the procedure. Invasion and transcytosis of the bacteria through epithelial cells were studied in vitro using a Madin-Derby canine kidney (MDCK) cell monolayer model. PCR for delta toxin gene was performed on all bacteria isolated, using Staphylococcus epidermidis as the control. Coagulase-negative staphylococci (CoNS) were invariably isolated from mice with prolonged ischemia (90 min) and reperfusion. When bacteria were fed into mice with only 30-min ischemia, an inoculum as low as 5 x 10(5) CFU/ml could induce bacteremia. No bacterial translocation was found in control mice even fed with a higher dose of bacteria (5 x 10(8) CFU/ml). In vitro experiments showed that CoNS failed to transcytose MDCK monolayer. These isolates were not cytotoxic to MDCK cells and contained no delta toxin gene. Bacterial translocation of CoNS occurred following severe bowel ischemia and reperfusion injury. Intact mucosa integrity readily prevented bacterial translocation; however, bacterial translocation could occur in rats following mild IRI in the presence of a higher number of CoNS in the gut.

Animals↗
PubMed2003

Reduced apoptosis in newborn compared to adult rat intestine after ischemia-reperfusion injury.

The pathogenesis of necrotizing enterocolitis (NEC) is unknown. Ischemia and reperfusion (I/R) injury has been considered to be a major contributing factor. More recent reports have noted that apoptosis is a significant and perhaps the principal contributor to cell death after I/R. Some reports revealed that infants with NEC and perforated bowel can completely recover with drainage alone. This study aims to assess the ability of newborn rat intestine to resist apoptosis after I/R injury compared with adult rat intestine. Intestines from 10 groups of rats (n = 6 for each study group) were studied: (1) normal control group; (2) ischemia group, receiving vascular occlusion for 60 min; (3) I/R groups receiving vascular occlusion for 60 min and reperfusion for 15, 30, and 60 min, respectively. Apoptosis was quantified by TUNEL methods. Statistical analysis was performed using ANOVA with Dunn's test. TUNEL-positive cells per 10 crypts were significantly increased in the ischemia and I/R groups compared to the control group. The peak number of positive cells by TUNEL was recognized 30 min after reperfusion in adult and newborn rats and then reduced gradually. The newborn rats had significantly less TUNEL-positive cells per 10 crypts than adult rats subjected to I/R injury (p < 0.05). We demonstrated that the activation of apoptosis occurred after intestinal I/R injury, especially during the reperfusion phase. The newborn intestine was more resistant to I/R injury and thus may have significant clinical application.

Aging↗