Biomedical subjects

Po-Ren Hsueh

Publications and source records attributed to Po-Ren Hsueh.

150 records · Page 9Linked to original sources

PubMed2002

Antimicrobial resistance in Streptococcus pneumoniae, Taiwan.

Taiwan has one of the highest levels of antibiotic-resistant pneumococcus in the world. Pneumococcal isolates not susceptible to penicillin first appeared in Taiwan in 1986; in 1995 an increase in the prevalence of nonsusceptibility to penicillins, extended-spectrum cephalosporins, trimethoprim-sulfamethoxazole, and macrolides as well as multidrug resistance began to be recognized. With the persistence of antibiotic selective pressure, resistance in some antibiotics reached a high plateau (beta-lactam antibiotics) or continued to increase (macrolides), while novel resistance (fluoroquinolones) emerged in the last 3 years. Widespread distribution of some novel resistant 23F and 19F clones (and the international epidemic of 23F clones) contributes further to the rapid increase of resistance. Because Streptococcus pneumoniae is a major pathogen that causes community-acquired lower respiratory tract infections and meningitis in adults and children, antibiotic-resistance in this organism is a serious problem.

Drug Resistance↗

PubMed2002

Antimicrobial drug resistance in pathogens causing nosocomial infections at a university hospital in Taiwan, 1981-1999.

To determine the distribution and antimicrobial drug resistance in bacterial pathogens causing nosocomial infections, surveillance data on nosocomial infections documented from 1981 to 1999 at National Taiwan University Hospital were analyzed. During this period, 35,580 bacterial pathogens causing nosocomial infections were identified. Candida species increased considerably, ranking first by 1999 in the incidence of pathogens causing all nosocomial infections, followed by Staphylococcus aureus and Pseudomonas aeruginosa. Candida species also increased in importance as bloodstream infection isolates, from 1.0% in 1981-1986 to 16.2% in 1999. The most frequent isolates from urinary tract infections were Candida species (23.6%), followed by Escherichia coli (18.6%) and P. aeruginosa (11.0%). P. aeruginosa remained the most frequent isolates for respiratory tract and surgical site infections in the past 13 years. A remarkable increase in incidence was found in methicillin-resistant S. aureus (from 4.3% in 1981-1986 to 58.9% in 1993-1998), cefotaxime-resistant E. coli (from 0% in 1981-1986 to 6.1% in 1993-1998), and cefotaxime-resistant Klebsiella pneumoniae (from 4.0% in 1981-1986 to 25.8% in 1993-1998). Etiologic shifts in nosocomial infections and an upsurge of antimicrobial resistance among these pathogens, particularly those isolated from intensive care units, are impressive and alarming.

Anti-Bacterial Agents↗

PubMed2002

Primary liver abscess caused by one clone of Klebsiella pneumoniae with two colonial morphotypes and resistotypes.

Two diabetic patients with primary liver abscess, who initially responded unsatisfactorily to intravenous ceftriaxone or cefoxitin treatment and had abscess drainage, were found to be infected with a single clone of Klebsiella pneumoniae with two different colonial morphotypes and resistotypes. Primary liver abscess caused by second-generation cephalosporin-resistant K. pneumoniae strains may be an emerging problem in Taiwan.

Adult↗

PubMed2002

In vitro activities of antimicrobial combinations against clinical isolates of Stenotrophomonas maltophilia.

BACKGROUND AND PURPOSE: Stenotrophomonas maltophilia, a major pathogen causing nosocomial infection, is inherently resistant to multiple antimicrobial agents. Evaluation of the effectiveness of recommended therapeutic options for S. maltophilia infections is crucial, particularly in areas with high antimicrobial resistance in this nosocomial pathogen. METHODS: The in vitro activities of ceftazidime (CAZ), ticarcillin-clavulanate (TIM), amikacin (AN), ciprofloxacin (CIP), and trimethoprim-sulfamethoxazole (TMP-SMZ) against 102 clinical isolates of S. maltophilia collected from January 1998 to December 1999 at a university hospital were evaluated. The disk diffusion and agar dilution susceptibilities of individual agents against these isolates were determined concomitantly. Errors between results obtained by the two methods were identified based on the guidelines for Acinetobacter species provided by the National Committee for Clinical Laboratory Standards. Activities of three two-drug combinations (AN + CIP, CAZ + CIP, and TIM + TMP-SMZ) against 32 of these isolates were analyzed using the checkerboard synergy test. RESULTS: Among the agents tested, TMP-SMZ was the most active against S. maltophilia (83.3% susceptible), followed by CIP (63.7%), CAZ (39.2%), TIM (36.2%), and AN (20.5%). Errors (very major and major) between the results obtained by the disk diffusion and agar dilution methods occurred at a high frequency for AN (15% and 3%), CAZ (8% and 6%), and CIP (3% and 3%). Synergy or partial synergy of antimicrobial agent combinations was detected predominantly with CAZ + CIP (81.3%) and TIM + TMP-SMZ (84.4%) but not with AN + CIP (37.5%). No antagonism was detected with any drug combinations. CONCLUSION: The dilution method is preferable to the disk diffusion method for susceptibility testing of S. maltophilia isolates, particularly for testing with AN, CAZ, and TIM, which have considerable error rates between the results obtained by the two methods. The findings from the synergy test suggest that TIM + TMP-SMZ and CAZ + CIP combinations are the treatments of choice for infections caused by S. maltophilia.

Anti-Bacterial Agents↗

PubMed2002

Phaeohyphomycosis caused by Exophiala species in immunocompromised hosts.

Exophiala species are rarely implicated in clinical diseases. In the past 2 years, we have treated phaeohyphomycosis caused by Exophiala species in three immunocompromised patients. Two of these patients presented with subcutaneous abscess or cutaneous verrucous lesions due to Exophiala jeanselmei. The former, an 81-year-old woman, had pulmonary tuberculosis and the latter, a 62-year-old man, had undergone heart transplantation and was receiving immunosuppressive treatment. The third patient, a 62-year-old woman, had acute lymphoblastic leukemia and developed lymphadenitis due to Wangiella (Exophiala) dermatitidis. In each case, the fungus was discovered on a Gram stain of the aspirated material and was identified by conventional tests. One patient died of bacterial pneumonia with acute respiratory distress syndrome and the other two were treated successfully with surgical excision and antifungal agents. With the more frequent and widespread use of immunosuppressive agents, the incidence of Exophiala infection will certainly increase. Surgical excision or debridement with or without antifungal agents may offer the possibility of cure for phaeohyphomycosis due to Exophiala species.

Aged↗

PubMedDate not supplied

Group B streptococcus infection in infancy: 21-year experience.

In this hospital-based review, clinical presentations associated with Group B streptococcus (GBS) infections in children occurring between January 1980 and March 2000 were analyzed. Among the 25 infants with invasive group B streptococcal infections, 9 (36%) were early onset diseases (EOD), 12 (48%) were late onset diseases (LOD), and 4 (16%) occurred beyond the third month of life. Eight of the nine (89%) EOD cases manifested during the first day of life and three (33%) were premature births. Common presentations in GBS infection were fever (75%), poor activity (25%), respiratory distress (25%), lethargy (20%), and irritability (20%). Seizure occurred in 31% of infants with meningitis. Pneumonia (66%) and case-fatality rate (33.3%) were significantly higher in EOD than in LOD. Meningitis was the major manifestation (77%) of LOD and had severe sequelae in 40% of cases. Eight strains were assayed for antibiotic sensitivity and they were all susceptible to penicillin, ampicillin, cefotaxime, and vancomycin. The susceptibilities to erythromycin and clindamycin were 62% and 75%, respectively. Most of the strains from blood or cerebrospinal fluid were type III.

Humans↗