Higher mortality of severe influenza patients with probable aspergillosis than those with and without other coinfections.

BACKGROUND/PURPOSE: Aspergillus-associated infection might comprise up to 23-29% of severe influenza patients from the community throughout stay in an intensive care unit (ICU). In Taiwan, cases of severe influenza with aspergillosis are increasingly reported. Therefore, we describe the relative risk of mortality among severe influenza patients with aspergillosis and other coinfections compared to severe influenza patients without Aspergillus coinfections. METHODS: We retrospectively reviewed 124 adult patients with severe influenza in a tertiary medical center in southern Taiwan from January 2015 through March 2016. The definition of probable aspergillosis required abnormal radiological findings and positive Aspergillus galactomannan (GM) antigen and/or Aspergillus isolation. RESULTS: Probable aspergillosis (detected throughout the whole course) and other coinfections (only community-acquired) were diagnosed in 21 (17%) and 38 (31%) of all patients respectively. Klebsiella pneumoniae (36.8%), Pseudomonas aeruginosa (31.6%) and Staphylococcus aureus (31.6%) were the most frequent isolates of other coinfections. In-ICU mortality of Aspergillus group (66.7%) was significantly higher than other coinfections (23.7%, p = 0.001) or control group without coinfections (15.4%, p < 0.001), with significant odds ratios after adjusting for important variables. The factor of GM index ≥0.6 had a 19.82 (95% CI, 4.91 to 80.07, p < 0.0001) odds of expiring in an ICU among the Aspergillus group. CONCLUSION: Dual Aspergillus and influenza infection is emerging in southern Taiwan. Meanwhile, community-acquired P. aeruginosa should be listed in the common copathogens with severe influenza. The 67% mortality linked to aspergillosis highlights the need for physicians to focus attention on patients with GM ≥ 0.6.

Developing a mobile electronic D2B checklist for treatment of ST elevation myocardial infarction patients who need a primary coronary intervention.

ST elevation myocardial infarction (STEMI), one main type of acute myocardial infarction with high mortality, requires percutaneous coronary intervention (PCI) with balloon inflation. Current guidelines recommend a door-to-balloon (D2B) interval (i.e., starts with the patient's arrival in the emergency department and ends when PCI with a catheter guidewire and balloon inflation crosses the culprit lesion) of no more than 90 min. However, promptly implementing PCI requires coordinating various medical teams. Checklists can be used to ensure consistency and operating sequences when executing complex tasks in a clinical routine. Developing an effective D2B checklist would enhance the care of STEMI patients who need PCI. Mobile information and communication technologies have the potential to greatly improve communication, facilitate access to information, and eliminate duplicated documentation without the limitations of space and time. In a research project by the Chi Mei Medical Center, "Developing a Mobile Electronic D2B Checklist for Managing the Treatment of STEMI Patients Who Need Primary Coronary Intervention," a prototype version of a mobile checklist was developed. This study describes the research project and the four phases of the system development life cycle, comprising system planning and selection, analysis, design, and implementation and operation. Face-to-face interviews with 16 potential users were conducted and revealed highly positive user perception and use intention toward the prototype. Discussion and directions for future research are also presented.

Decline in rates of acquired multidrug-resistant tuberculosis after implementation of the directly observed therapy, short course (DOTS) and DOTS-Plus programmes in Taiwan.

OBJECTIVES: To investigate the impact of the directly observed therapy, short course (DOTS) and DOTS-Plus strategies on changes in resistance profiles among Mycobacterium tuberculosis (MTB). METHODS: We performed a retrospective analysis of resistance profiles among isolates of MTB obtained from 2160 consecutive patients with culture-confirmed pulmonary tuberculosis (TB) between 2005 and 2011 at a referral centre in southern Taiwan. RESULTS: Of the 2160 patients, 70 (3.2%) had primary multidrug-resistant (MDR)-TB, 178 (8.2%) had acquired MDR-TB, 10 (0.5%) had primary extensively drug-resistant (XDR)-TB, 23 (1.1%) had acquired XDR-TB and 5 (0.2%) had totally drug-resistant (TDR)-TB. Trend analysis revealed that the rates of acquired MDR-TB were significantly lower after implementation of the DOTS and DOTS-Plus programmes (P < 0.01). There was a significant negative correlation between the coverage rates of the DOTS and DOTS-Plus programmes and the rates of acquired MDR-TB (r = -0.84, P = 0.02 and r = -0.92, P = 0.03, respectively). The rates of resistance to rifampicin, isoniazid, ofloxacin, moxifloxacin, levofloxacin and para-aminosalicylic acid also decreased significantly during the study period. However, the rates of primary MDR-TB remained stable (P = 0.11). Multivariate logistic regression analysis showed that age ranging from 45 to 64 years, positive acid-fast stain results at the initiation of treatment and treatment without DOTS were independent risk factors associated with acquired MDR-TB. In addition, previous treatment for TB (100% versus 19% for TDR-TB and non-TDR-TB, P < 0.01) and treatment without DOTS (80% versus 44% for TDR-TB and non-TDR-TB, P = 0.18) were risk factors for TDR-TB. CONCLUSIONS: DOTS and DOTS-Plus are both effective at preventing the acquisition of MDR-TB in Taiwan.

Recurrent bacteremia caused by the Acinetobacter calcoaceticus-Acinetobacter baumannii complex.

This study investigated the clinical and microbiological characteristics of patients with recurrent bacteremia caused by the Acinetobacter calcoaceticus-Acinetobacter baumannii (ACB) complex at a medical center. All ACB complex isolates associated with recurrent bacteremia were identified to the genomic species level using a 16S-23S rRNA gene intergenic spacer sequence-based method. Genotypes were determined by the random amplified polymorphic DNA patterns generated by arbitrarily primed PCR and by pulsotypes generated by pulsed-field gel electrophoresis. Relapse of infection was defined as when the genotype of the recurrent isolate was identical to that of the original infecting strain. Reinfection was defined as when the genospecies or genotype of the recurrent isolate differed from that of the original isolate. From 2006 to 2008, 446 patients had ACB complex bacteremia and 25 (5.6%) had recurrent bacteremia caused by the ACB complex. Among the 25 patients, 12 (48%) had relapse of bacteremia caused by A. nosocomialis (n = 7) or A. baumannii (n = 5). Among the 13 patients with reinfection, 5 (38.5%) had reinfection caused by different genospecies of the ACB complex. Most of the patients were immunocompromised, and most of the infection foci were catheter-related bloodstream infections. The overall in-hospital mortality rate was 33.3%. A. baumannii isolates had lower antimicrobial susceptibility rates than A. nosocomialis and A. pittii isolates. In conclusion, relapse of ACB complex bacteremia can develop in immunocompromised patients, especially those with central venous catheters. Molecular methods to identify the ACB complex to the genospecies level are essential for differentiating between reinfection and relapse of bacteremia caused by the ACB complex.

Intermediate bioelectrolyte changes after phospho-soda or polyethylene glycol precolonoscopic laxatives in a population undergoing health examinations.

BACKGROUND: Colonoscopy is a common procedure for diagnosing and screening colon cancer and other bowel-related diseases. Many studies have pointed out that using phospho-soda as a bowel preparation can cause obvious electrolyte abnormalities or acute kidney injury. Nonetheless, there are few studies related to its prevalence and risk factors in the population undergoing health examinations. Our aim was to compare the biochemical and electrolyte changes after using two commonly used bowel preparation regimens in this population. METHODS: In this retrospective study, we collected data about participants who, before a screening colonoscopy, used oral phospho-soda laxatives in 2006, and those who used polyethylene glycol-based laxatives in 2005. Several serum biochemical and electrolyte profiles were compared between the two groups. Additional risk factors of hyperphosphatemia, a well-known side effect of phospho-soda, were also derived. RESULTS: We enrolled a total of 2270 participants (1321 in 2005; 1449 in 2006). The basic demographic data of the two groups were not statistically different. Nonetheless, between the two groups, some serum biochemical and electrolytic data differed significantly: in those using oral phospho-soda laxatives, we found a higher prevalence of hyperuricemia, hypocalcemia, hypokalemia, hypernatremia and hyperphosphatemia. Further analyses showed that using oral phospho-soda laxatives was a risk factor for hyperphosphatemia; conversely, being male was a protective factor. CONCLUSION: Oral phospho-soda laxatives indeed influence the biochemical and electrolyte profiles of persons undergoing health examinations. One should be careful when interpreting bioelectrolytic data while using phospho-soda as a bowel preparation.

Infections caused by unusual Methylobacterium species.

We describe six patients with hospital-acquired bacteremia caused by Methylobacterium species, including M. radiotolerans (n = 2), M. thiocyanatum (n = 2), M. aminovorans (n = 1), and M. lusitanum (n = 1), which were confirmed to species level by 16S rRNA gene sequence analysis. Among these patients, five had catheter-related bacteremia and all had favorable outcomes.

Acinetobacter baumannii and Acinetobacter genospecies 13TU and 3 bacteraemia: comparison of clinical features, prognostic factors and outcomes.

OBJECTIVES: To investigate the clinical impact of different genospecies of the Acinetobacter calcoaceticus-Acinetobacter baumannii complex (ACB complex; A. baumannii, Acinetobacter gen. sp. 13TU and Acinetobacter gen. sp. 3) on the severity of bacteraemia. METHODS: We retrospectively compared the clinical features and outcomes of patients with bacteraemia caused by A. baumannii, Acinetobacter gen. sp. 13TU or Acinetobacter gen. sp. 3. The genospecies were identified using oligonucleotide array sequence analysis (interspacer sequence), and the clonality of Acinetobacter gen. sp. 13TU and 3 isolates was determined by PFGE analysis. RESULTS: A total of 215 patients with bacteraemia due to ACB complex were evaluated. Among them, 117 (54.4%) had A. baumannii bacteraemia, 77 (35.8%) had Acinetobacter gen. sp. 13TU bacteraemia and 21 (9.8%) had Acinetobacter gen. sp. 3 bacteraemia. A. baumannii bacteraemia was associated with a higher 14 day mortality rate (P < 0.001), a higher 30 day mortality rate (P < 0.001) and a higher in-hospital mortality rate than bacteraemia due to Acinetobacter gen. sp. 13TU or Acinetobacter gen. sp. 3. Independent prognostic factors for the 30 day mortality included the Charlson co-morbidity index (P < 0.001) and Pitt bacteraemia score (P < 0.001). Bloodstream infection caused by a multidrug-resistant A. baumannii isolate appeared to be associated with a poor outcome (P = 0.069). There was no clonal spread of Acinetobacter gen. sp. 13TU or Acinetobacter gen. sp. 3 during the study period. CONCLUSIONS: Bacteraemia due to multidrug-resistant strains but not A. baumannii per se appears to be associated with poor outcome.

Correlation between antibiotic consumption and resistance of Gram-negative bacteria causing healthcare-associated infections at a university hospital in Taiwan from 2000 to 2009.

OBJECTIVES: This study investigated the correlation between antibiotic consumption and antimicrobial resistance in Gram-negative bacteria causing healthcare-associated infections at a university hospital in Taiwan from 2000 to 2009. METHODS: Disc susceptibility data of Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Serratia marcescens, Proteus spp., Pseudomonas aeruginosa, Acinetobacter spp., Stenotrophomonas maltophilia and other non-fermentative Gram-negative bacilli causing healthcare-associated infections were evaluated. Data on annual patient-days and annual consumption (defined daily doses per 1000 patient-days) of extended-spectrum cephalosporins, ß-lactam/ß-lactamase inhibitor combinations, carbapenems, aminoglycosides and fluoroquinolones were analysed. RESULTS: The trend of total consumption of extended-spectrum cephalosporins, ß-lactam/ß-lactamase inhibitor combinations, carbapenems, aminoglycosides and fluoroquinolones significantly increased between 2000 and 2003 and remained stable between 2004 and 2009. The decreasing use of gentamicin and amikacin in recent years was associated with increasing susceptibility of E. coli, E. cloacae, S. marcescens and P. aeruginosa to gentamicin, as well as increasing susceptibility of P. aeruginosa to amikacin. The use of piperacillin/tazobactam was positively correlated with the prevalence of piperacillin/tazobactam-resistant E. coli and S. maltophilia. In contrast, the use of cefotaxime and piperacillin/tazobactam was negatively correlated with the prevalence of cefotaxime-resistant E. coli and piperacillin/tazobactam-resistant S. maltophilia, respectively. The consumption of fluoroquinolones was positively correlated with the rates of ciprofloxacin-resistant E. coli, piperacillin/tazobactam-resistant P. aeruginosa and ceftazidime-resistant S. maltophilia. CONCLUSIONS: The relationship between antibiotic prescription and the rates of resistance for Gram-negative bacteria is complicated; every type of antimicrobial agent or even individual agent can have distinct associations with different pathogens.

Shortening the Time of the Identification and Antimicrobial Susceptibility Testing on Positive Blood Cultures with MALDI-TOF MS.

The current processes used in clinical microbiology laboratories take ~24 h for incubation to identify the bacteria after the blood culture has been confirmed as positive and fa further ~24 h to report the results of antimicrobial susceptibility tests (ASTs). Patients with suspected bloodstream infection are treated with empiric broad-spectrum antibiotics but delayed targeted antimicrobial therapy. This study aimed to develop a method with a significantly shortened turnaround time for clinical application by identifying the optimal incubation period of a subculture. A total of 188 positive blood culture samples obtained from Nov. 2019 to Aug. 2020 were included. Compared to the conventional 24-h incubation for bacterial identification, our approach achieved 96.1% and 97.4% identification accuracy after shortening the incubation time to 4.5 and 3.5 h for gram-positive (GP) and gram-negative (GN) bacterial samples, respectively. Samples from short-term incubation without any intermediate step or process were directly subjected to analysis with the Phoenix M50 AST. Compared to the conventional disk diffusion AST, the category agreements for GP (excluding Streptococcus spp.), Streptococcus spp., and GN bacterial samples were 91.8%, 97.5%, and 92.7%, respectively. Our approach significantly reduced the average turnaround time from 48 h to 28 h for reporting bacterial identity and decreased average AST from 72 h to 50.3 h compared to the conventional methods. Accordingly, this approach allows a physician to prescribe the appropriate antibiotic(s) ~21.7 h earlier, thereby improving patient outcomes.

Increasing incidence of nontuberculous mycobacteria, Taiwan, 2000-2008.

To assess the species distribution and epidemiologic trends of nontuberculous mycobacteria, we examined isolates from patients in Taiwan. During 2000-2008, the proportion increased significantly from 32.3% to 49.8%. Associated disease incidence increased from 2.7 to 10.2 cases per 100,000 patients. Mycobacterium avium complex and M. abscessus were most frequently isolated.

Fatal Citrobacter farmeri meningitis in a patient with nasopharyngeal cancer.

We describe the case of an adult male with nasopharyngeal carcinoma who had meningitis caused by Citrobacter farmeri. The isolate was confirmed as C. farmeri by two commercial identification systems and 16S rRNA gene analysis. The patient developed multiorgan failure and died despite antibiotic treatment with in vitro active agents (ceftriaxone and meropenem).

Risk factors for mortality in patients with persistent methicillin-resistant Staphylococcus aureus bacteraemia in a tertiary care hospital in Taiwan.

OBJECTIVES: To investigate the determinants of outcome in patients with persistent methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia. METHODS: All patients >or=18 years old with MRSA bacteraemia for >or=7 days from 2000 to 2008 treated at National Taiwan University Hospital were investigated. The associations of mortality with clinical characteristics, management and vancomycin MICs for serial MRSA isolates were analysed. RESULTS: Persistent MRSA bacteraemia occurred in 227 patients. Decreasing trends in the incidence of MRSA bacteraemia (P < 0.001) and persistent MRSA bacteraemia (P = 0.031) were found. Elevated vancomycin MICs for subsequent MRSA isolates were found in 49 (24.6%) of 199 patients, especially those with infective endocarditis (41.9% versus 21.4%; P = 0.027). Metastatic infection [odds ratio (OR) 5.23; 95% confidence interval (CI) 2.17-12.59; P < 0.001], congestive heart failure (OR 4.78; 95% CI 2.19-10.42; P < 0.001) and elevated vancomycin MICs for subsequent MRSA isolates (OR 3.21; 95% CI 1.46-7.07; P = 0.004) were independent predictors of MRSA-related mortality, while metastatic infection (OR 3.01; 95% CI 1.45-6.28, P = 0.003) and congestive heart failure (OR 2.85; 95% CI 1.44-5.56, P = 0.003) were predictors of 30 day mortality. No significant impact of empirical glycopeptide therapy on MRSA-related (P = 0.89) or 30 day mortality (P = 0.26) was found. The 30 day mortality rate was lower in patients who received complete foci eradication (35.6% versus 51.1%; P = 0.03). CONCLUSIONS: Congestive heart failure and metastatic infections were predictors of mortality. Isolates with decreased susceptibility to vancomycin that emerged during persistent MRSA bacteraemia were associated with mortality. Aggressive attempts to completely eradicate foci should be encouraged.

Diagnostic usefulness of enzyme-linked immunospot assay for interferon-gamma for tuberculosis in cancer patients.

The interferon-γ enzyme-linked immunospot assay (ELISPOT) has been demonstrated to be useful in the diagnosis of active tuberculosis (TB). In this study we aimed to evaluate the diagnostic performance of the ELISPOT assay in cancer patients with suspected pulmonary TB. Eighty-one cancer patients with suspected pulmonary TB were prospectively enrolled from April 2007 to December 2008, to investigate the diagnostic sensitivity and specificity of the ELISPOT assay. Of the 38 patients with TB, 33 (86.8%) had positive ELISPOT results. Of the 43 patients without TB, the results of the ELISPOT assay were negative in 35 (81.3%) patients. The overall sensitivity was 86.8%, specificity 81.3%, positive predictive value 80.5% and negative predictive value 87.5%. No significant difference was noted for the diagnostic performance of the ELISPOT assay for diagnosing TB between solid cancer and haematological cancer patients. In addition, a quantitative study did not show that TB patients with solid cancers have a better response than haematological cancer patients as measured by spot-forming cells per 10(6) peripheral blood mononuclear cells after exposure to early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10). In conclusion, the ELISPOT assay could be a useful supplementary tool for the diagnosis of pulmonary TB among cancer patients, irrespective of cancer type.

Comparative in vitro activities of nemonoxacin, doripenem, tigecycline and 16 other antimicrobials against Nocardia brasiliensis, Nocardia asteroides and unusual Nocardia species.

OBJECTIVES: The aim of this study was to assess the in vitro activities of nemonoxacin (a novel non-fluorinated quinolone), doripenem, tigecycline and 16 other antimicrobial agents against the Nocardia species. METHODS: MICs of 19 antimicrobial agents for 125 clinical isolates of the Nocardia species were determined by the broth microdilution method. RESULTS: Nocardia brasiliensis (n = 61), Nocardia asteroides (n = 45), Nocardia flavorosea (n = 5), Nocardia otitidiscaviarum (n = 4), Nocardia farcinica (n = 3), Nocardia beijingensis (n = 2), Nocardia puris (n = 2) and one each of Nocardia nova, Nocardia jinanensis and Nocardia takedensis were identified based on a 16S rRNA gene sequencing analysis. For N. brasiliensis isolates, the MIC(90)s of the tested quinolones were in the order nemonoxacin < gemifloxacin = moxifloxacin < levofloxacin = ciprofloxacin, and the MIC(90)s of the tested carbapenems were in the order doripenem = meropenem < ertapenem < imipenem. Tigecycline had a lower MIC(90) (1 mg/L) than linezolid (8 mg/L). For N. asteroides isolates, the MIC(90)s of the tested quinolones were in the order nemonoxacin < gemifloxacin = moxifloxacin < levofloxacin < ciprofloxacin, and the MIC(90)s of the tested carbapenems were in the order doripenem = meropenem = imipenem < ertapenem. For the other 19 Nocardia species isolates, nemonoxacin showed good activity with the lowest MIC(90) of the tested quinolones. Among the four tested carbapenems, doripenem and meropenem had comparatively lower MIC(90)s. CONCLUSIONS: The results of this in vitro study suggest that nemonoxacin, linezolid and tigecycline show promise as treatment options for nocardiosis. Further investigation of their clinical role is warranted.

Readmission to the intensive care unit: an indicator that reflects the potential risks of morbidity and mortality of surgical patients in the intensive care unit.

PURPOSE: To investigate the characteristics and outcomes of surgical patients who were readmitted to the intensive care unit (ICU). METHODS: The data were collected for all readmissions to the surgical ICUs in a tertiary hospital in the year 2003. RESULTS: Of all the 945 ICU discharges, 110 patients (11.6%) were readmitted. They had a longer initial ICU stay (8.05 +/- 7.17 vs 5.22 +/- 4.95, P < 0.001) and were older and in a more severe condition than those not readmitted, but with a longer hospital stay and higher mortality rate (40% vs 3.6%, P < 0.001). A total of 26.4% of the readmission patients had an early readmission (<48 h), with a lower mortality rate than those with a late readmission (24.1% vs 45.7%, P = 0.049). A total of 46.4% of the patients were readmitted with the same diagnosis while the rest were readmitted with a new complication. Respiratory disease was the most common diagnosis for patients readmitted with a new complication (66.1%). The nonsurvivors had a significantly higher second Acute Physiology and Chronic Health Evaluation (APACHE II) score (22.1 +/- 8.8 vs.14.6 +/- 7.4, P < 0.001) and second Therapeutic Intervention Scoring System (TISS) score (30.1 +/- 8.7 vs 24.7 +/- 7.6, P = 0.001) and a longer stay in the first ICU admission (10.4 +/- 9 days vs 6.4 +/- 5 days, P = 0.010). A multivariate analysis showed that the first ICU length of stay and the APACHE II score at the time of readmission were the two risk factors for mortality. CONCLUSION: The mortality of surgical patients with ICU readmission was high with respiratory complications being the most important issue.

Ceftazidime-Avibactam versus Meropenem for the Treatment of Complicated Intra-Abdominal Infections.

This study reports an integrated analysis of three randomized controlled trials to compare the clinical efficacies and safety of the ceftazidime-avibactam (CAZ-AVI) combination and meropenem in the treatment of adult patients with complicated intra-abdominal infections (cIAIs). Overall, a total of 1677 patients (CAZ-AVI: 835 patients; meropenem: 842 patients) were included in this analysis. CAZ-AVI had a clinical cure rate at test of cure in the clinically evaluable (CE) population similar to that of meropenem (OR, 0.88; 95% CI, 0.58-1.32; I2 = 0%). Similar trends were also observed in the modified intent-to-treat (MITT) population (OR, 0.80; 95% CI, 0.59-1.09; I2 = 0%) and microbiological evaluable (ME) population (OR, 0.73; 95% CI, 0.32-1.68; I2 = 0%). In terms of clinical cure rate at the end of treatment, the efficacy of CAZ-AVI was comparable to that of meropenem in the CE population (OR, 0.77; 95% CI, 0.47-1.25; I2 = 0%), MITT population (OR, 0.70; 95% CI, 0.47-1.06; I2 = 5%), and ME population (OR, 1.26; 95% CI, 0.39-4.08; I2 = 0%). CAZ-AVI had a similar risk of (i) treatment emergent adverse events (TEAEs) (OR, 1.03; 95% CI, 0.79-1.36; I2 = 38%), (ii) any serious adverse events (OR, 0.97; 95% CI, 0.67-1.40; I2 = 0%), (iii) discontinuation of study drug due to TEAE (OR, 2.14; 95% CI, 1.00-4.57), and iv) all-cause mortality (OR, 1.66; 95% CI, 0.78-3.53; I2 = 0%) when compared with meropenem. In conclusion, CAZ-AVI had comparable efficacy and safety profile to those of meropenem in the treatment of cIAI.

Extensively drug-resistant Mycobacterium tuberculosis during a trend of decreasing drug resistance from 2000 through 2006 at a Medical Center in Taiwan.

BACKGROUND: Drug resistance rates are one of the most important aspects in the national tuberculosis (TB) control program, and drug-resistant TB, especially extensively drug-resistant (XDR) TB, is not well understood in Taiwan. The objectives of this study were to investigate the prevalence of drug resistance from 2000 through 2006 and to identify XDR TB isolates to elucidate the clinical characteristics of patients with XDR TB at National Taiwan University Hospital. METHODS: The prevalence of drug resistance among clinical, nonduplicate Mycobacterium tuberculosis isolates was analyzed. Testing of susceptibility to antituberculosis agents, including isoniazid, rifampicin, ethambutol, streptomycin, rifabutin, ofloxacin, ethinamide, and para-aminosalicylic acid, was performed using the proportional method. Minimum inhibitory concentrations of amikacin, capreomycin, isepamycin, linezolid, cycloserine, ciprofloxacin, levofloxacin, moxifloxacin, and gemifloxacin were determined for 40 available multidrug-resistant M. tuberculosis isolates. RESULTS: Significant decreasing trends in rates of resistance to isoniazid, ethambutol, and at least 1 of the 3 first-line agents were observed among 2625 M. tuberculosis isolates from 2000 through 2006. Among these 2625 isolates, 150 (5.7%) were multidrug resistant, and 10 M. tuberculosis isolates (0.4%) fulfilled the definition of XDR M. tuberculosis. Nine (90%) of 10 patients with XDR TB had a previous history of TB and received anti-TB treatment before acquisition of XDR TB. CONCLUSIONS: The remaining high prevalence of multidrug-resistant TB and the presence of XDR TB during a trend of decreasing drug resistance are alarming. Continuous surveillance of clinical isolates of M. tuberculosis is needed to identify XDR TB, especially in patients who have a history of TB and have received prior anti-TB treatment.