SYNOPSIS Cur rent Status of Antimicrobial Resistance in Taiwan Po-Ren Hsueh,* Cheng-Yi Liu,† and Kwen-Tay Luh* While some trends in antimicrobial resistance rates are universal, others appear to be unique for specific regions. In Taiwan, the strikingly high prevalence of resistance to macrolides and streptogramin in clinical isolates of gram-positive bacteria correlates with the widespread use of these agents in the medical and farming communities, respectively. The relatively low rate of enterococci that are resistant to glycopeptide does not parallel the high use of glycopeptides and extended-spectrum beta-lactams in hospitals. The evolving problem of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneu- moniae isolates is substantial, and some unique enzymes have been found. Recently, some gram-nega- tive bacteria (e.g., Pseudomonas aeruginosa and Acinetobacter baumannii) that are resistant to all available antimicrobial agents including carbapenems have emerged. A lem worldwide, affecting every country to some degree. ntimicrobial resistance has become a major health prob- It is an inevitable consequence of the inappropriate use of anti- biotics in humans and animals. In Europe and North America, methicillin-resistant Staphylococcus aureus (MRSA), penicil- lin-nonsusceptible Streptococcus pneumoniae (PNSSP), van- comycin-resistant enterococci (VRE), and extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have emerged and spread into communities and hospitals. In Tai- wan, the widespread use of antimicrobial agents in primary care clinics and animal husbandry has allowed the rapid emer- gence of resistant bacteria. During the last 2 decades, many antimicrobial agents—such as extended-spectrum cepha- losporins, carbapenems, fluoroquinolones, and aminoglyco- sides—have been introduced and empirically used as first-line drugs to treat these resistant bacteria (1,2). This has further accelerated the development and dissemination of drug-resis- tant bacteria. Previous studies in Taiwan have clearly demon- strated the remarkably high prevalence of some critically resistant bacteria, such as MRSA, PNSSP, and macrolide- resistant streptococci (1,2). In addition, several multidrug- resistant bacteria, including ones resistant to carbapenems and fluoroquinolones and pan-drug-resistant gram-negative bacilli, have been isolated from different hospitals (3-6). Approval of Antibiotics Table 1 shows the years that selected antibiotics were approved in Taiwan. These antibiotics are now widely used to treat various infections, including community-acquired and nosocomial infections. Until now, two gylcopeptides (vanco- mycin and teicoplanin), two carbapenems (imipenem and meropenem), four macrolides (erythromycin, roxithromycin, clarithromycin, and azithromycin), and six quinolones (nalid- ixic acid, norfloxacin, ofloxacin, lomefloxacin, ciprofloxacin, and levofloxacin) have been available for clinical use in Tai- *National Taiwan University Hospital, National Taiwan University Col- lege of Medicine, Taipei, Taiwan; †and Taipei Veterans General Hospi- tal and National Yang-Ming University, Taipei, Taiwan wan. Most of these drugs were also readily available at drug- stores without prescription before 1995. Drug-Resistant Bacteria The following drug-resistance data were collected from a nationwide resistance survey (Surveillance from Multicenter Antimicrobial Resistance in Taiwan) of clinical isolates (including those recovered from hospitals and outpatients) from 12 major hospitals as well as isolates causing nosocomial infections from National Taiwan University Hospital (NTUH) in 2000 in Taiwan. These hospitals are located in different parts of the country. The number of beds in these hospitals ranged from 800 to 3,200. All these data were derived by using the disk-diffusion method (7). Some dilution antimicrobial susceptibility and epidemiol- ogy studies, including >100 strains published in English-lan- guage journals from January 1995 through 2001, were also included. Rather than provide a comprehensive review of all resistance problems in Taiwan, our aim was to point out some of the more critical resistance problems threatening the treat- ment of infections caused by Staphylococcus species, S. pyo- genes, Streptococcus pneumoniae, Enterococcus species, and Table 1. Year of approval of selected antimicrobial agents in Taiwan Antimicrobial agent Erythromycin Oxacillin Gentamicin Cefotaxime Amikacin Ceftazidime Imipenem Vancomycin Ciprofloxacin Cefepime Year of approval 1968 1970 1981 1983 1986 1988 1988 1983 1990 1997 132 Emerging Infectious Diseases • Vol. 8, No. 2, February 2002