High prevalence of HIV-1 transmitted drug resistance and factors associated with time to virological failure and viral suppression in Taiwan.

BACKGROUND: Integrase strand transfer inhibitor (InSTI)-based regimens have become the major first-line treatment for HIV-1-infected patients in Taiwan. Transmitted drug resistance (TDR) and several clinical characteristics are associated with time to virological failure or viral suppression; however, these have not been investigated in Taiwan. OBJECTIVES: To determine the impact of several factors on treatment outcomes in HIV-1-infected patients in Taiwan. METHODS: The cohort included 164 HIV-1 treatment-naive patients in Taiwan from 2018 to 2020. Blood specimens were collected to determine the genotypic drug resistance using the Stanford University HIV drug resistance database. Cox proportional hazards models were used to identify factors associated with time to virological failure or viral suppression. RESULTS: The prevalence of TDR in Taiwan was 27.4% and an increasing trend was seen from 2018 to 2020. TDR mutations related to NNRTIs were the most prevalent (21%) while TDR to InSTIs remained at a relatively low level (1.3%). A baseline HIV-1 viral load of ≥100 000 copies/mL was associated with a shorter time to virological failure [multivariate hazard ratio (mHR) 7.84; P = 0.018] and longer time to viral suppression (mHR 0.46; P < 0.001). Time to viral suppression was shorter in patients receiving InSTI-based regimens (mHR 2.18; P = 0.006). Different InSTI-based regimens as initial treatment did not affect the treatment outcomes. CONCLUSIONS: This study found an increasing trend of HIV-1 TDR prevalence from 2018 to 2020 in Taiwan. Baseline HIV-1 viral load and receiving InSTI-based regimens are important factors associated with time to virological failure or viral suppression.

Risk factors of tuberculosis after liver transplant in a tertiary care hospital.

BACKGROUND: Tuberculosis (TB) is a serious opportunistic infection in liver transplant (LT) recipients with a high rate of morbidity and mortality. This study aims to clarify the frequency and risk factors for tuberculosis in LT recipients. METHODS: A total of 884 LT recipients were investigated retrospectively at China Medical University Hospital, Taichung, Taiwan. We performed a case-control study (1:2) to investigate the potential risk factors and disease onset of TB after LT. RESULTS: Among the 884 LT recipients, 25 of TB cases (2.8%) were reported from 2009 to 2016. The overall incidence of TB was 744 cases per 100,000 patient-year, which was 18-fold higher than the general population in Taiwan. The median time to develop TB after liver transplant was 20 months. Of the TB cases, 15 were pulmonary TB and 10 were extra-pulmonary TB. Five cases of those extra-pulmonary TB occurred in the first post-transplant year. Overall five-year survival rate was 63.3%. Multivariate analyses identified apical fibrotic change in pre-transplant computed tomographic (CT) finding and the exposure to mammalian target of rapamycin (mTOR) inhibitors before TB event as independent risk factors for TB development (Odd ratio (OR) 10.79, 95% confidence interval (CI), 1.73-67.49, p = 0.01; OR 3.847, 95% CI 0.80-18.51, P = 0.09, respectively). CONCLUSION: TB incidence in LT recipients is high in this study. Among those post-transplant recipients with long-term immunosuppression, abnormal CT finding and exposure to mTOR inhibitors before liver transplant might be the risk factors for TB.

Clinical characteristics, treatments, and outcomes of hematogenous pyogenic vertebral osteomyelitis, 12-year experience from a tertiary hospital in central Taiwan.

BACKGROUND: In Taiwan, studies about hematogenous pyogenic vertebral osteomyelitis (HPVO) are limited. We conducted a retrospective study to evaluate the clinical presentations, treatment, and outcomes of patients with the diagnosis of HPVO. METHOD: This 12.5-year retrospective study included patients with a diagnosis of HPVO. Medical records of all HPVO patients were thoroughly reviewed and their clinical data were analyzed by the SPSS software. RESULT: 414 HPVO cases were included and the mean age was 61.6 ± 13.4 years. The mean duration of symptoms was 29 ± 35.3 days and pain over the affected site was reported by most patients (86.0%). Gram-positive bacteria, especially Staphylococcus aureus (162/399 = 40.6%), were the main HPVO pathogens. Escherichia coli (42/399 = 10.5%) was the most common gram-negative isolate. Surgery was performed in 68.8% of cases and the mean duration of total antibiotic treatment was 104.7 ± 77.7 days. All-cause mortality and recurrence rates were 6.3% and 18.8%, respectively. In multivariate analysis, polymicrobial infection (OR: 4.154, 95% CI: 1.039-16.604, p = 0.044), multiple vertebral body involvement (OR: 2.202, 95% CI: 1.088-4.457, p = 0.028), abscess formation treated with antibiotics alone (OR: 2.912, 95% CI: 1.064-7.966, p = 0.037), and the duration of antimicrobial treatment less than 4 weeks (OR: 3.737, 95% CI: 1.195-11.683, p = 0.023) were associated with HPVO recurrence. CONCLUSION: In Taiwan, HPVO mainly affected the elderly and S. aureus remained the most common HPVO pathogen. In patients with risk factors associated with HPVO recurrence, a longer duration (≥6 weeks) of antimicrobial therapy is suggested.

Clinical features, antifungal susceptibility, and outcome of Candida guilliermondii fungemia: An experience in a tertiary hospital in mid-Taiwan.

BACKGROUNDS: Candida guilliermondii is rarely isolated from clinical specimen. C. guilliermondii fungemia is seldom reported in the literature. The aims of this study were to report the clinical features, antifungal susceptibility, and outcomes of patients with C. guilliermondii fungemia. METHODS: From 2003 to 2015, we retrospectively analyzed the clinical and laboratory data of patients with C. guilliermondii fungemia in a tertiary hospital in mid-Taiwan. We performed a multivariable logistic regression analysis to identify the risk factors of mortality. The Sensititre YeastOne microtiter panel assessed the susceptibility of antifungal agents. RESULTS: In this study, we identified 36 patients with C. guilliermondii fungemia. The median age of patients was 50.5 years (range, 17 days to 96 year) and 20 cases (56%) were male. The incidence of C. guilliermondii fungemia was 0.05 per 1000 admissions. Malignancy was the most common co-morbidity, and 25 (69%) patients had central venous catheter in place. Thirty-day overall mortality was 16.7%. In multivariate logistical regression analysis, catheter retention was an independent risk factor of mortality. According to epidemiological cutoff values, most clinical isolates (21/22, 95.5%) belonged to the wild-type MIC distributions for amphotericin B and flucytosine; however, the isolates were less susceptible to fluconazole (68%) and echinocandins (77-91%). CONCLUSION: Despite the lower mortality rate associated with C. guilliermondii fungemia, the removal of a central venous catheter remained an independent factor influencing the outcome of patients. The clinical significance of less susceptibility of C. guilliermondii to triazoles and echinocandins remains to be elucidated.

Effect of antiretroviral therapy use and adherence on the risk of hyperlipidemia among HIV-infected patients, in the highly active antiretroviral therapy era.

HIV-infected patients exposed to antiretroviral therapy (ART) have an increased risk for hyperlipidemia and cardiovascular disease. We performed a longitudinal, comprehensive, and population-based study to investigate the cumulative effect of different types of ART regimens on hyperlipidemia risk in the Taiwanese HIV/ART cohort. A total of 13,370 HIV-infected patients (2,674 hyperlipidemia and 10,696 non-hyperlipidemia patients) were recruited after matching for age, gender, and the first diagnosis date of HIV infection by using the National Health Insurance Research Database in Taiwan. Hyperlipidemia risk associated with cumulative ART use, ART adherence, and their combination was assessed. The matched hyperlipidemia group had a larger number of patients using ART and a higher incidence of comorbidities, specifically, respiratory disease and diabetes. Patients with high ART dosage and dose-dependent manner adherence, respectively, demonstrated an increased risk of hyperlipidemia. For single ART regimens, patients receiving nucleoside reverse-transcriptase inhibitors (NRTI/NRTI)- containing regimen had the highest hyperlipidemia risk, followed by protease inhibitor (PI)- containing and non-NRTI- containing regimens. For combination ART regimens, patients receiving a NRTI/NRTI + PI regimen had the highest hyperlipidemia risk. An increased cumulative drug dose was observed in patients who received the PI, NRTI/NRTI, NRTI, and NNRTI regimens in the hyperlipidemia group, when compared to the non-hyperlipidemia group. In conclusion, ART cumulative use, adherence, and regimen may affect hyperlipidemia risk among HIV-infected patients in a dose-dependent manner.

Isolated tuberculous liver abscess in an immunocompetent adult patient: A case report and literature review.

Tuberculous liver abscess is a rare disease entity even in endemic areas of Mycobacterium tuberculosis. It is usually accompanied by pulmonary tuberculosis or enteric tuberculosis. Further, an isolated tuberculous liver abscess is extremely rare. The disease is diagnosed by laparotomy or postmortem autopsy in most cases, and some authors adopted a 9-month antituberculosis regimen. We herein report a case of an isolated tuberculous liver abscess that initially manifested as persistent fever and general malaise, which was diagnosed by liver biopsy and treated successfully with a 6-month antituberculosis regimen and percutaneous abscess drainage.

Prompt Oseltamivir Therapy Reduces Medical Care and Mortality for Patients With Influenza Infection: An Asian Population Cohort Study.

There are limited population-based studies on the progress of oseltamivir therapy for influenza infection.Using insurance claims data of 2005, 2009, and 2010, the authors established an "in-time" cohort and a "lag-time" cohort representing influenza patients taking the medicine within and not within 1 week to examine the treatment progress. Incident outpatient visit, emergency care and hospitalization, and fatality were compared between the 2 cohorts in the first week and the second week of follow-up periods, after the oseltamivir therapy.A total of 112,492 subjects diagnosed with influenza on oseltamivir therapy in 2005, 2009, and 2010 were identified. The multivariate logistic regression analysis showed that the in-time treatment was superior to the lag-time treatment with less repeat outpatient visits, hospitalizations, and fatality. The overall corresponding in-time treatment to lag-time treatment odds ratios (OR) were 0.50, 0.54, and 0.71 (all P value < 0.05), respectively. The in-time to lag-time ORs of all events were 0.50 in 2009 and 0.54 in 2010.Our study demonstrates that the in-time oseltamivir therapy leads to significantly better treatment outcomes. Oseltamivir should be administered as early as the onset of influenza symptoms appears.

Management and outcome of adults with skin and soft tissue infection caused by methicillin-resistant Staphylococcus aureus in a tertiary hospital in central Taiwan.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has been increasingly causing skin and soft tissue infections (SSTIs). Only limited studies have made comparisons between incision and drainage (I&D) alone and I&D with adjunctive antibiotic therapy for treatment effects, and most of the studies were conducted before the emergence of MRSA. This study was to evaluate whether antibiotics provide added benefit to I&D alone for purulent MRSA SSTIs. METHODS: This retrospective study collected data on SSTI patients, including patient demographics, treatment strategies, antibiotic susceptibilities of the infecting MRSA isolates, and clinical outcomes over the course of 24 months. RESULTS: Antimicrobial drug susceptibility rate were 100% for vancomycin, teicoplanin, and linezolid. Among the 211 patients, 7.6% were treated solely with I&D (Group A), 62.6% were treated via I&D with adjunctive antibiotic (Group B), and 29.8% patients received only antibiotics (Group C). The cure rate was highest in Group A (93.8%), followed by Group B (90.9%) and Group C (77.8%). Combining Group B and Group C, patients who were treated appropriately demonstrated a higher cute rate (91.3% vs. 75.4%, p = 0.005). Multivariate analysis showed that Group B was more likely to be successfully treated compared to Group C (odds ratio = 2.51, 95% confidence interval = 1.01-6.25, p = 0.047), whereas no difference between Group A and Group B was found (odds ratio = 2.09, 95% confidence interval = 0.20-22.34, p = 0.542, data not shown). CONCLUSION: Surgical intervention is the definitive therapy for purulent SSTIs. Adjunctive antibiotic therapy increased the cure rate and appropriateness of prescription is influential.

National surveillance on vancomycin-resistant Enterococcus faecium in Taiwan: emergence and widespread of ST414 and a Tn1546-like element with simultaneous insertion of IS1251-like and IS1678.

Cases of bacteremia caused by vancomycin-resistant E. faecium (VRE-fm) increased significantly in Taiwan. The present multicenter surveillance study was performed to reveal the associated epidemiological characteristics. In 2012, 134 non-repetitive VRE-fm isolates were prospectively collected from 12 hospitals in Taiwan. Antimicrobial susceptibility, pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and analysis of van genes and Tn1546 structures were investigated. Two isolates carried vanB genes, while all the remaining isolates carried vanA genes. Three isolates demonstrated a specific vanA genotype - vanB phenotype. Nine (6.7%) isolates demonstrated tigecycline resistance, and all were susceptible to daptomycin and linezolid. Molecular typing revealed 58 pulsotypes and 13 sequence types (STs), all belonged to three major lineages 17, 18, and 78. The most frequent STs were ST17 (n = 48, 35.8%), ST414 (n = 22, 16.4%), and ST78 (n = 16, 11.9%). Among the vanA harboring isolates, eight structure types of the Tn1546-like element were demonstrated. Type I (a partial deletion in the orf1 and insertion of IS1251-like between the vanS - vanH genes) and Type II (Type I with an additional insertion of IS1678 between orf2 - vanS genes) were the most predominant, consisted of 60 (45.5%) and 62 (47.0%) isolates, respectively. The increase of VRE-fm bacteremia in Taiwan may be associated with the inter- and intra-hospital spread of some major STs and horizontal transfer of vanA genes mostly carried on two efficient Tn1546-like elements. The prevailing ST414 and widespread of the Type II Tn1546-like elements are an emerging problem that requires continuous monitoring.

Nosocomial neonatal legionellosis associated with water in infant formula, Taiwan.

We report 2 cases of neonatal Legionella infection associated with aspiration of contaminated water used in hospitals to make infant formula. The molecular profiles of Legionella strains isolated from samples from the infants and from water dispensers were indistinguishable. Our report highlights the need to consider nosocomial legionellosis among neonates who have respiratory symptoms.

Ring finger protein 39 genetic variants associate with HIV-1 plasma viral loads and its replication in cell culture.

BACKGROUND: The human immunodeficiency virus (HIV-1) exploits host proteins to complete its life cycle. Genome-wide siRNA approaches suggested that host proteins affect HIV-1 replication. However, the results barely overlapped. RING finger protein 39 (RNF39) has been identified from genome-wide association studies. However, its function during HIV-1 replication remains unclear. METHODS AND RESULTS: We investigated the relationship between common RNF39 genetic variants and HIV-1 viral loads. The effect of RNF39 protein knockdown or overexpression on HIV-1 replication was then investigated in different cell lines. Two genetic variants were associated with HIV-1 viral loads. Patients with the ht1-GG/GG haplotype presented lower RNF39 expression levels and lower HIV-1 viral load. RNF39 knockdown inhibited HIV-1 expression. CONCLUSIONS: RNF39 protein may be involved in HIV-1 replication as observed in genetic studies on patients with HIV-1 and in in vitro cell cultures.

Correlation of virulence genes to clinical manifestations and outcome in patients with Streptococcus dysgalactiae subspecies equisimilis bacteremia.

BACKGROUND/PURPOSE: Streptococcus dysgalactiae subsp. equisimilis (SDSE) is increasingly recognized as a human pathogen responsible for invasive infection and streptococcal toxic shock syndrome (STSS). The pathogen possesses virulence genes that resemble those found in Streptococcus pyogenes (GAS). We analyzed the association between these specific toxic genes, clinical presentations, and outcome in patients with SDSE infections. METHODS: Patients (older than 18 years) with community-acquired invasive bacteremia caused by SDSE bacteremia who were undergoing treatment at China Medical University Hospital from June 2007 to December 2010 were included in this study. Multiplex polymerase chain reaction was performed to identify virulence genes of the SDSE isolates. Demographic data, clinical presentations, and outcome in patients with SDSE infections were reviewed and analyzed. RESULTS: Forty patients with 41 episodes of SDSE bacteremia were reviewed. The median age of the patients with SDSE infection was 69.7 years; 55% were female and 78% had underlying diseases. Malignancy (13, 33%) and diabetes mellitus (13, 33%) were the most common comorbidities. The 30-day mortality rate was 12%. Compared with the survivors, the non-survivors had a higher rate of diabetes mellitus (80% vs. 26%), liver cirrhosis (60% vs.11%), shock (60% vs.17%), STSS (60% vs. 8%), and a high Pittsburgh bacteremia score >4 (40% vs. 6%). Most isolates had scpA, ska, saga, and slo genes, whereas speC, speG, speH, speI, speK, smez, and ssa genes were not detected. speA gene was identified only in one patient with STSS (1/6, 17%). All isolates were susceptible to penicillin, cefotaxime, levofloxacin, moxifloxacin, vancomycin, and linezolid. CONCLUSION: In invasive SDSE infections, most isolates carry putative virulence genes, such as scpA, ska, saga, and slo. Clinical SDSE isolates in Taiwan remain susceptible to penicillin cefotaxime, and levofloxacin.

Intraventricular antimicrobial therapy in postneurosurgical Gram-negative bacillary meningitis or ventriculitis: a hospital-based retrospective study.

BACKGROUND: Postneurosurgical Gram-negative bacillary meningitis (GNBM) or ventriculitis is a serious issue. Intraventricular (IVT) therapy has been applied; however, its effectiveness remains controversial, and the adverse drug effects are considerable. METHODS: The demographic data, treatment strategies, and clinical outcomes of patients with postneurosurgical GNBM or ventriculitis were recorded. RESULTS: From 2003 to 2011, data on 127 episodes of infection in 109 patients were collected, and 15 episodes in 14 patients were treated using a sequential combination of intravenous antibiotics and IVT therapy; others received intravenous antibiotics alone. The average age of patients who received a sequential combination with IVT therapy was 48.9 years, and 71.4% of the patients were men. The regimens used for IVT therapies included gentamicin (n = 4), amikacin (n = 7), and colistin (n = 4). After meningitis had been diagnosed, the average period that elapsed before initiation of IVT therapy was 25.4 days, and the average duration of IVT therapy was 13.3 days. The most frequently isolated pathogen from cerebrospinal fluid (CSF) was Acinetobacter baumannii, followed by Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Serratia marcescens. The cure rate was 73.3%. Of note, the mean period to sterilize the CSF after appropriate IVT antibiotic treatment was 6.6 days. There were no incidents of seizure or chemical ventriculitis during this IVT therapy. CONCLUSION: The findings of this study suggest that IVT antibiotic therapy is a useful option in the treatment of postneurosurgical GNBM or ventriculitis, especially for those with a treatment-refractory state.

Report of a 63-case series of Candida empyema thoracis: 9-year experience of two medical centers in central Taiwan.

BACKGROUND: Candida empyema thoracis is a serious complication of invasive candidiasis with high mortality. However, the treatment for Candida empyema remains controversial. We conducted a 9-year retrospective study to analyze the treatments and factors associated with the mortality of patients with Candida empyema thoracis in two medical centers in central Taiwan. METHODS: The medical records of all patients with positive Candida culture from pleural effusion between October 2002 and September 2011 were reviewed. The demographic data, treatment regimens, and factors associated with mortality were analyzed. RESULTS: During the period of this study, 102 patients were identified. Sixty-three of these patients fulfilled the enrollment criteria, and their data were analyzed. Three-quarters of these patients were male, and the median age of these patients was 69. Thirty-five (55.6%) patients had contiguous infection. The crude mortality rate was 61.9%. Candida albicans was the most common isolate, and malignancy was the most common underlying disease. Patients with advanced age, a higher Charlson's score, shock status, respiratory failure, and noncontiguous infection had a higher mortality rate. Those who had received surgical intervention had a better outcome. In multivariate analysis, the shock status, respiratory failure, and noncontiguous infection source were associated with a higher mortality risk. CONCLUSION: Candida empyema thoracis is a severe invasive candidiasis with high mortality rate. Shock status, respiratory failure, and noncontiguous infection were factors associated with a higher mortality rate. Surgical intervention or drainage may improve the treatment outcome, especially in patients with contiguous infection.

Variants in ZNRD1 gene predict HIV-1/AIDS disease progression in a Han Chinese population in Taiwan.

Patients demonstrate notable variations in disease progression following human immunodeficiency virus (HIV) infection. We aimed to identify ZNRD1 and RNF39 genetic variants linked to AIDS progression. We conducted a genetic association study in HIV-1-infected Han Chinese patients residing in Taiwan. The clinical characteristics of 143 HIV-1-infected patients were measured, and patients were split into 2 groups: AIDS progression and AIDS non-progression. Genotyping of ZNRD1 and RNF39 was performed in all participants. We found that patients in the AIDS progression group had higher HIV-1 viral loads and lower CD4 cell counts than did patients in the AIDS non-progression group. The frequency of the AA genotype of ZNRD1 (rs16896970) was lower in the AIDS progression group than in the AIDS non-progression group. Patients with AA genotypes had lower levels of HIV-1 viral loads and higher levels of CD4 cell counts than did patients with AG+GG genotypes. AIDS progression in patients with the AA group is significantly different from that in patients with the AG and GG groups by using Kaplan-Meier survival analysis. The hazard ratio for progression was lower in the AA group than in the AG and GG groups. We identified a SNP that contributes to AIDS progression in HIV-1-infected patients in this population. This SNP had a significant protective influence on AIDS progression, and polymorphisms of the ZNRD1 gene may play a role in the pathogenesis of HIV-1 infection.

Echinocandins in invasive candidiasis.

We summarise a recent meeting, sponsored by Pfizer Inc., where experts in Asia shared their clinical experience in managing IC. The echinocandins have demonstrated good activity against non-albicans infections and also azole-resistant strains, both preclinically and in recent clinical trials. As well as proving efficacious, echinocandins have a favourable safety profile and are well tolerated, including among inpatient subpopulations, such as transplant recipients and those with renal or hepatic dysfunction. In addition the echinocandins generally have minimal drug-drug interactions, unlike the oral azoles, which have multiple effects on cytochrome P450-mediated drug metabolism. Echinocandins are characterised by a good safety profile, few drug-drug interactions and good susceptibilities. With the increase in potentially azole-resistant non-albicans infections, echinocandins may become the first-line treatment of choice for many patients.

Anti-IFN-γ autoantibodies in adults with disseminated nontuberculous mycobacterial infections are associated with HLA-DRB1*16:02 and HLA-DQB1*05:02 and the reactivation of latent varicella-zoster virus infection.

Adult patients with disseminated nontuberculous mycobacterial (dNTM) infections usually have severe immune system defects. Recently, several studies have shown that anti-IFN-γ autoantibodies may play an important role in the pathogenicity of dNTM infections. A considerable proportion of reported cases of anti-IFN-γ autoantibodies show either clinical or laboratory evidence of autoimmune disease. In the present study, we identified 19 formerly healthy adults who later developed dNTM infections, of whom 17 were further investigated immunologically. High-titer anti-IFN-γ autoantibodies capable of inhibiting IL-12 production in vitro were found in the plasma of all of these patients. In addition to dNTM infection, 35% and 71% of our patients also suffered from salmonellosis and herpes zoster, respectively. This observation suggests that IFN-γ may be crucial in controlling salmonella infection and reactivating latent varicella-zoster virus infection in humans. 2 HLA alleles, DRB1*16:02 DQB1*05:02 (odds ratio 8.68; 95% confidence interval, 3.47-21.90; P = 1.1 × 10(-6); Pc = 3.08 × 10(-5) and odds ratio 7.16; 95% confidence interval, 3.02-17.05; P = 1 × 10(-7); Pc = 1.4 × 10(-6), respectively), were found in 82% (14 of 17) of our patients. In conclusion, our data suggest that anti-IFN-γ autoantibodies may play a critical role in the pathogenesis of dNTM infections and reactivation of latent varicella-zoster virus infection and are associated with HLA-DRB1*16:02 and HLA-DQB1*05:02.

In vitro susceptibilities of non-Enterobacteriaceae isolates from patients with intra-abdominal infections in the Asia-Pacific region from 2003 to 2010: results from the Study for Monitoring Antimicrobial Resistance Trends (SMART).

The Study for Monitoring Antimicrobial Resistance Trends (SMART) is an international surveillance study designed to monitor resistance trends among aerobic and facultative Gram-negative bacilli (GNB) isolated from intra-abdominal infections. During 2003-2010, a total of 20710 GNB isolates were collected at medical centers in China, Hong Kong, Korea, New Zealand, and Taiwan. The susceptibility profiles of 2252 isolates of non-Enterobacteriaceae GNB were determined. At least 10 isolates of a given organism were required for that organism to be included in the analysis. Pseudomonas aeruginosa was the leading organism (49.2% of non-Enterobacteriaceae GNB), followed by Acinetobacter baumannii (21.5%), Aeromonas spp. (11.6%), and Stenotrophomonas maltophilia (9.1%). All the other species/genera made up less than 2%. The rates of susceptibility of the four major organisms were examined for two different time periods and according to whether the isolates had been obtained <48 h after hospitalization or ≥ 48 h after hospital admission. P. aeruginosa, Aeromonas spp., and S. maltophilia showed sustained levels of susceptibility to several antimicrobial agents in the two time periods, whereas A. baumannii exhibited very high rates of resistance to most antimicrobial agents including imipenem. Nosocomial P. aeruginosa and A. baumannii were more resistant than community-acquired pathogens, although this was not the case for Aeromonas spp. and S. maltophilia. Worldwide and regional surveillance is necessary to guide empirical antimicrobial therapy for infections due to non-Enterobacteriaceae GNB.

Antimicrobial susceptibility profiles of Gram-negative bacilli isolated from patients with hepatobiliary infections in Taiwan: results from the Study for Monitoring Antimicrobial Resistance Trends (SMART), 2006-2010.

We investigated the trends in antimicrobial resistance among species of Gram-negative bacilli isolated from patients with hepatobiliary tract infections in Taiwan during the period 2006-2010 as part of the Study for Monitoring Antimicrobial Resistance Trends (SMART). During the study period, 1032 isolates of Gram-negative bacilli that had been collected from patients with hepatobiliary infections were tested for susceptibility to 12 antimicrobial agents in accordance with the Clinical and Laboratory Standards Institute guidelines. Enterobacteriaceae accounted for the majority (n = 874, 84.7%) of isolates and Escherichia coli was the most common pathogen (n = 323, 31.3%). There were significantly more E. coli (P = 0.001) and Proteus mirabilis (P = 0.031) isolates collected from patients who had been hospitalized for less than 48 h and significantly more Serratia marcescens (P = 0.035) and Pseudomonas aeruginosa (P = 0.008) isolates collected from patients who had been hospitalized for 48 h or longer. The prevalence of extended-spectrum ß-lactamase (ESBL)-producing pathogens was low. The decline in susceptibility rates with time was remarkable for ceftazidime (P = 0.036), ciprofloxacin (P = 0.029), and levofloxacin (P = 0.018). The most effective antibiotics, i.e., those that were active against more than 90% of Enterobacteriaceae, were amikacin, cefepime, imipenem, ertapenem, and piperacillin-tazobactam. Susceptibility of P. aeruginosa to anti-pseudomonal agents was greater than 80%. In this study, we found an overall increase in resistance to antimicrobial agents among Gram-negative bacilli isolated from patients with hepatobiliary tract infections in Taiwan. Surveillance of antimicrobial susceptibility and updates of treatment guidelines are recommended to help achieve optimal therapy for patients with hepatobiliary infections.