Trends in microbial profile of burn patients following an event of dust explosion at a tertiary medical center.

BACKGROUND: Microbial infection is the main cause of increased morbidity and mortality in burn patients, especially infections caused by multiple drug-resistant organisms (MDRO). The purpose of this study was to explore major microbial trends in burn patients. METHODS: This retrospective study was conducted at burn wards and intensive care units, where burn patients were admitted following an event of dust explosion. Data were collected for a number of variables including severity of burns, demographic and clinical characteristics, laboratory data, and therapeutic devices. RESULTS: A total of 1132 specimens were collected from 37 hospitalized burn patients with mean TBSA of 46.1%.The most commonly isolated species were Staphylococcus spp. (22.4%). The highest rate of antibiotic resistance was observed in carbapenem-resistant A. baumannii (14.6%), followed by methicillin-resistant S. aureus (11.3%). For each additional 10% TBSA, the isolation of MDRO increased 2.58-17.57 times (p < 0.05); for each additional 10% of the third-degree burn severity, the risk of MDRO significantly decreased by 47% (95% CI, 0.38-0.73, p < 0.001) by Cox model. CONCLUSIONS: The proportion of overall microbial isolates increased with the increase in TBSA and duration of time after burns. The extent of TBSA was the most important factor affecting MDRO.

Is fluoroquinolone monotherapy a useful alternative treatment for Pseudomonas aeruginosa bacteraemia?

PURPOSE: Pseudomonas aeruginosa bacteraemia is associated with high mortality, and most monotherapies are beta-lactam-based. We aimed to investigate clinical outcomes of definitive fluoroquinolone monotherapy versus beta-lactam monotherapy for P. aeruginosa bacteraemia. METHODS: This retrospective study enrolled adult patients receiving definitive monotherapy with beta-lactam or fluoroquinolone between November 2013 and November 2014 at Taipei Veterans General Hospital. The independent risk factors for 28-day mortality were analyzed by logistic regression and propensity score-adjusted analysis. RESULTS: Among the 105 patients enrolled, 78 patients received beta-lactams and 27 received fluoroquinolones (20 with ciprofloxacin and 7 with levofloxacin). Primary bacteraemia (39.0%) and urinary tract infections (37.1%) were the most common sources of bacteraemia. The 28-day mortality rate was 11.1% for those receiving fluoroquinolones and 32.1% for those receiving beta-lactams (P = 0.062). The 28-day mortality rate between the two groups stratified by APACHE II and Pitt bacteraemia scores showed no significant differences in each category. Propensity score-adjusted multivariate analysis revealed that definitive therapy with a fluoroquinolone was not associated with 28-day mortality (OR 0.42; 95% CI 0.08-2.23; P = 0.305). CONCLUSIONS: Fluoroquinolone might be an alternative to beta-lactam as a definitive monotherapy for P. aeruginosa bacteraemia provided they are active in vitro. Our results could be a basis for further studies and provide a possible target for antibiotic stewardship interventions in P. aeruginosa bacteraemia.

Anaerobic coverage as definitive therapy does not affect clinical outcomes in community-onset bacteremic biliary tract infection without anaerobic bacteremia.

BACKGROUND: Antibiotics with anaerobic coverage are widely used for the treatment of biliary tract infection (BTI), even in the absence of isolated anaerobes. The current study aimed to investigate the differences in clinical outcomes in patients with community-onset bacteremic BTIs without anaerobic bacteremia, treated with vs. without anti-anaerobic coverage. METHODS: A retrospective analysis was conducted at a medical center in Taiwan from September 2014 to March 2016. Patients with community-onset bacteremic BTIs without anaerobic bacteremia and who were treated with appropriate antibiotics were analyzed. The clinical outcomes were compared between patients treated with and without anti-anaerobic coverage as definitive therapy after the blood culture reports were available. Multivariable and propensity score-adjusted analysis were used to identify the risk factors associated with treatment failure. RESULTS: Among the enrolled 87 patients, 63 and 24 patients were treated with and without anaerobic coverage, respectively. Escherichia coli (55.2%) and Klebsiella pneumoniae (23.0%) were the most common organisms isolated from the blood cultures. The rate of treatment failure (relapse and 28-day mortality) was similar between the groups with and without anaerobic coverage (20.6% vs. 16.7%, p = 0.677). Propensity score-adjusted multivariable analysis revealed that definitive therapy without anaerobic coverage was not a predisposing factor for treatment failure (OR = 0.92, 95% CI 0.18-4.67, p = 0.916). CONCLUSIONS: Definitive therapy without anaerobic coverage does not affect the outcomes of patients with community-onset bacteremic BTIs without anaerobes isolated from blood. Our results might provide a possible target for antibiotic stewardship interventions in BTIs.

Clinical outcomes and safety of remdesivir in hospitalized individuals with COVID-19, with or without severe renal impairment.

BACKGROUND: The use of remdesivir in patients with coronavirus disease 2019 (COVID-19) and severe renal impairment has been approved; however, limited clinical data exist. Accordingly, we aimed to compare outcomes and adverse events associated with remdesivir in hospitalized patients with COVID-19, with and without severe renal impairment. METHODS: Hospitalized patients with COVID-19 undergoing a 5-day remdesivir course at Taipei Veterans General Hospital from April 1 to July 31, 2022, were enrolled. Comparative analysis of outcomes and safety between patients with or without severe renal impairment (estimated glomerular filtration rate of < 30 mL/min per 1.73 m2) were conducted. Prognostic factors associated with 28-day mortality in patients with severe renal impairment were investigated using logistic regression analysis. RESULTS: A total of 671 hospitalized patients, including 132 patients with severe renal impairment, who received a 5-day course of remdesivir were analyzed. The 28-day mortality was higher in patients with severe renal impairment than in patients without severe renal impairment (15.2% vs. 7.8%). The proportion of patients with acute kidney injury (AKI) and deteriorated liver function after completing remdesivir therapy was similar between the patients with and without severe renal impairment, and the recovery rate of AKI was similar in both groups. The sequential organ failure assessment score was an independent factor associated with 28-day mortality in patients with severe renal impairment. CONCLUSIONS: Remdesivir was well-tolerated in hospitalized patients with COVID-19, regardless of renal function. Our findings support the recent recommendation to administer remdesivir in patients with severe renal impairment.

Klebsiella pneumoniae liver abscess in diabetic patients: association of glycemic control with the clinical characteristics.

BACKGROUND: Klebsiella pneumoniae liver abscess (KPLA) has been reported with increasing frequency in East Asian countries in the past 3 decades, especially in Taiwan and Korea. Diabetes is a well-known risk factor for KPLA and highly associated with septic metastatic complications from KPLA. We investigated the association of glycemic control in diabetic patients with the clinical characteristics of KPLA in Taiwan. METHODS: Adult diabetic patients with KPLA were identified retrospectively in a medical center from January 2007 to January 2012. Clinical characteristics were compared among patients with different levels of current hemoglobin A1c (HbA1c). Risk factors for metastatic infection from KPLA were analyzed. RESULTS: Patients with uncontrolled glycemia (HbA1c ≥ 7%) were significantly younger than those with controlled glycemia (HbA1c < 7%). Patients with uncontrolled glycemia had the trend to have a higher rate of gas-forming liver abscess, cryptogenic liver abscess, and metastatic infection than those with controlled glycemia. Cryptogenic liver abscess and metastatic infection were more common in the poor glycemic control group (HbA1c value >; 10%) after adjustment with age. HbA1c level and abscess < 5 cm were independent risk factors for metastatic complications from KPLA. CONCLUSIONS: Glycemic control in diabetic patients played an essential role in the clinical characteristics of KPLA, especially in metastatic complications from KPLA.

Prognostic factors for poor outcomes in patients with severe COVID-19 treated with remdesivir plus dexamethasone in Taiwan.

BACKGROUND: Coronavirus disease-2019 (COVID-19) remains a global public health concern, and remdesivir plus dexamethasone combination therapy is suggested for patients with severe disease. However, the factors associated with poor outcomes in these patients remain unclear. We identified the factors associated with poor outcomes in Taiwanese patients with severe COVID-19 treated with remdesivir plus dexamethasone. METHODS: Adults with severe COVID-19 (oxygen saturation <94% on room air or requiring supplemental oxygen) treated with remdesivir and dexamethasone were identified between 1 May and 31 July 2021. The main outcomes were 14-day non-recovery, 28-day mortality, and progression to respiratory failure requiring invasive mechanical ventilation or death in initially non-ventilated patients. The prognostic factors associated with poor outcomes were analyzed by multivariate logistic regression and Cox regression. RESULTS: Of the 110 patients treated with remdesivir and dexamethasone, 57 (51.8%) recovered within 14 days and 6 (5.5%) died within 28 days. Of the 89 initially non-ventilated patients, 12 (13.5%) progressed to respiratory failure or death. Charlson Comorbidity Index, SOFA score, and admission to remdesivir treatment interval were associated with 14-day non-recovery. C-reactive protein level was associated with 28-day mortality. Pneumonia Severity Index and admission to remdesivir treatment interval were associated with progression to respiratory failure requiring invasive mechanical ventilation or death in initially non-ventilated patients. CONCLUSION: High disease severity on admission and delayed initiation of remdesivir therapy were associated with poor outcomes in COVID-19 patients treated with remdesivir and dexamethasone.

Tenofovir use is associated with a decreased risk of hepatocellular carcinoma among men with HIV irrespective of coinfection status.

Background & Aims: Tenofovir is recommended as part of the first-line antiretroviral therapy (ART) to treat people living with HIV (PLWH) with HBV coinfection. However, the effects of tenofovir-containing ART on hepatocellular carcinoma (HCC) risk among PLWH with/without chronic hepatitis virus infections remain unclear. Methods: This study included 23,838 PLWH. All of them were males aged ≥20 years and followed prospectively during 2000-2017. Four major nationwide registries - the Human Immunodeficiency Virus surveillance database, Taiwan Cancer Registry, Death Certification System, and National Health Insurance Database - were applied to define ART and comorbidities and ascertain newly diagnosed HCC. Tenofovir-containing ART was identified through prescription records. Cox proportional hazards models were used to determine the association of tenofovir use with HCC incidence. Results: HCC incidence was lower among ever users of tenofovir than among never users (24.2 and 85.7 per 100,000 person-years, respectively). Ever users had significantly reduced HCC risk (adjusted hazard ratio 0.20, 95% CI 0.13-0.31). The effect of tenofovir use on reduced risk for HCC consistently favored never users across many prespecified subgroups, including HBV or HCV coinfection (p <0.05). The findings were consistent in subgroups of PLWH diagnosed with HIV before tenofovir's approval and in those born before the nationwide roll-out of neonatal HBV vaccination. Conclusions: Our findings underscore the need for randomized controlled trials of tenofovir in combination with long-acting injectable ART regimens to assess its safety and efficacy in PLWH, particularly in those with HBV or HCV coinfection. Impact and implications: Tenofovir's effect on the risk of hepatocellular carcinoma (HCC) among people living with HIV with hepatitis B or C coinfection remains under investigated. This nationwide prospective cohort study, comprising 23,838 men living with HIV, showed that tenofovir-containing antiretroviral therapy was associated with reduced risk of HCC (adjusted relative risk: 0.20, 95% CI 0.13-0.31), which was consistently observed across many prespecified subgroups. The effect of tenofovir use on HCC risk should be further investigated in PLWH, particularly following the development of long-acting injectable ART regimens.

The influence of low-level viremia on CD4+ cell count in human immunodeficiency virus-infected patients.

BACKGROUND: Following initiation of combined antiretroviral therapy, the majority of human immunodeficiency virus-infected patients experience immune reconstitution indicated by virologic suppression and an increase in peripheral CD4+ T-cell counts. Some patients may suffer from low-level viremia, which was reported to be significantly associated with acquired immunodeficiency syndrome cases, virologic failure, and death. We aimed to further investigate the influence of low-level viremia on CD4+ T-cell count. METHODS: In our study, we included human immunodeficiency virus-seropositive patients on combined antiretroviral therapy, for at least 6 months, who received at least one assessment of human immunodeficiency virus plasma viral load and CD4+ cell count every 6 months, from January 2009 to January 2019. The copy-year viremia was determined by calculating the area under the curve of the plasma human immunodeficiency virus viral load. RESULTS: When comparing patients with a mean CD4+ cell count <200 cells/µL, there was no significant difference between patients with a mean viral load <1000 copies/mL and patients with a mean viral load ≥1000 copies/mL (p = 0.219). Among those with a mean viral load <1000 copies/mL, a higher proportion of patients had a mean CD4+ cell count ≥500 cells/µL (p < 0.001). The mean CD4+ cell count of patients with copy-years viremia (log10) <4 (577.7, interquartile range 429.2-736.7) was significantly higher than that of patients with copy-years viremia (log10) ≥4 (443.3, interquartile range 319.0-558.4) (p < 0.001). In multivariate logistic regression analysis, we observed that malignancy without history, lower copy-years viremia, and high nadir CD4+ cell count were independent predictors of mean CD4+ cell count ≥500 cells/µL. CONCLUSION: Human immunodeficiency virus-infected patients with a history of malignancy, high copy-year viremia, and lower nadir CD4+ cell counts should be monitored carefully in clinical settings.

The impact of antimicrobial stewardship program designed to shorten antibiotics use on the incidence of resistant bacterial infections and mortality.

Reassessing the continuing need for and choice of antibiotics by using an antibiotic "time out'' program may reduce unnecessary treatment. This study aimed to explore the effect of an antibiotic stewardship program (ASP) on the antibiotics consumption, incidence of resistant bacterial infections and overall hospital mortality in a tertiary medical center during the study period 2012-2014. An ASP composed of multidisciplinary strategies including pre-prescription approval and post-approval feedback and audit, and a major "time out'' intervention (shorten the default antibiotic prescription duration) usage was introduced in year 2013. Consumption of antibiotics was quantified by calculating defined daily doses (DDDs). Interrupted time series (ITS) analysis was used to explore the changes of antibiotics consumption before and after intervention, accounting for temporal trends that may be unrelated to intervention. Our results showed that following the intervention, DDDs showed a decreased trend in overall (in particular the major consumed penicillins and cephalosporins), in both intensive care unit (ICU) and non-ICU, and in non-restrictive versus restrictive antibiotics. Importantly, ITS analysis showed a significantly slope change since intervention (slope change p value 0.007), whereas the incidence of carbapenem-resistant and vancomycin-resistant pathogens did not change significantly. Moreover, annual overall mortality rates were 3.0%, 3.1% and 3.1% from 2012 to 2014, respectively. This study indicates that implementing a multi-disciplinary strategy to shorten the default duration of antibiotic prescription can be an effective manner to reduce antibiotic consumption while not compromising resistant infection incidence or mortality rates.

Clinical characteristics and outcomes of 56 patients with pneumonia caused by carbapenem-resistant Klebsiella pneumoniae.

OBJECTIVES: Pneumonia caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) is associated with high mortality. However, clinical studies on CRKP infections often exclusively involve bacteraemia, with only a few studies having focused on pneumonia. This retrospective study was conducted to investigate the clinical and microbiological characteristics of pneumonia caused by CRKP. METHODS: Adult patients diagnosed with CRKP monomicrobial pneumonia treated with at least one active antimicrobial agent within 5 days of the pneumonia diagnosis were identified in a medical centre in Taiwan between January 2017 and April 2019. Clinical characteristics and outcomes of these patients were determined. Resistance mechanisms and capsular types of the CRKP isolates were determined by PCR. RESULTS: A total of 56 patients with CRKP monomicrobial pneumonia were identified. The 7-day and 14-day mortality rates were 7.1% and 23.2%, respectively. Malignancy [adjusted odds ratio (aOR) = 8.87, 95% confidence interval (CI) 1.66-47.26; P = 0.011] and Acute Physiology and Chronic Health Evaluation (APACHE) II score (aOR = 1.12, 95% CI 1-1.25; P = 0.048) were independently associated with 14-day mortality. Most CRKP clinical isolates were carbapenemase-producers (39/44; 88.6%), of which K. pneumoniae carbapenemase type 2 (KPC-2)-producing isolates were most prevalent (30/39; 76.9%). The most prevalent capsular type in these isolates was K47 (30/44; 68.2%). CONCLUSION: CRKP pneumonia is associated with high 14-day mortality. Malignancy and APACHE II score were independently associated with 14-day mortality.

The epidemiology and etiologies of respiratory tract infection in Northern Taiwan during the early phase of coronavirus disease 2019 (COVID-19) outbreak.

BACKGROUND: Coronavirus disease 2019 (COVID-19) manifests symptoms as common etiologies of respiratory tract infections (RTIs). During the pandemic of COVID-19, identifying the etiologies correctly from patients with RTI symptoms was crucial in not only disease control but preventing healthcare system from collapsing. By applying sensitive PCR-based molecular assays, we detected the etiologic agents and delineated the epidemiologic picture of RTIs in the early phase of COVID-19 pandemic. METHODS: From December 2019 to February 2020, we screened patients presented with RTIs using multiplex PCR-based diagnostic assays. Data from pediatric and adult patients were compared with different months and units in the hospital. RESULTS: Of all 1631 patients including 1445 adult and 186 pediatric patients screened, 8 viruses and 4 bacteria were identified. Positive rates were 25% in December, 37% in January, and 20% in February, with pediatric patients having higher positive rates than adults (Ps < 0.001). In pediatric patients, RhV/EnV was the most commonly detected, followed by parainfluenza viruses. Most Mycoplasma pneumoniae infection occurred in pediatric patients. RhV/EnV was the most commonly detected agent in pediatric patients admitted to intensive care units (ICUs), while influenza accounted for the majority of adult cases with critical illness. Noticeably, seasonal coronavirus ranked second in both adult and pediatric patients with ICU admission. CONCLUSION: While we focused on the pandemic of COVID-19, common etiologies still accounted for the majority of RTIs and lead to severe diseases, including other seasonal coronaviruses.

Anal human papillomavirus and its associations with abnormal anal cytology among men who have sex with men.

Human papillomavirus (HPV) infection contributes to most anal cancers and premalignant intraepithelial lesions. This study investigated anal HPV infections and cytological abnormalities among men who have sex with men (MSM). Sociodemographic characteristics and sexual behaviors were collected by using a structured questionnaire. Anal cytological results were examined, and HPV genotyping was performed by the Linear Array HPV Genotyping test. Logistic regression was used to estimate risk factors and their associations with high-risk HPV infection and cytological abnormalities. Among 163 MSM, 101 were seropositive for human immunodeficiency virus (HIV) and 62 were seronegative for HIV. The overall prevalence of HPV was 66.2%. A total of 61.9% and 48.2% of participants had never acquired any of either the quadrivalent or nonavalent vaccine HPV types, respectively. Cytological findings showed 15.3% atypical squamous cells of undetermined significance, 16.6% low-grade squamous intraepithelial lesion, 4.9% atypical squamous cells that cannot exclude high-grade squamous intraepithelial lesion and 17% high-grade squamous intraepithelial lesion. The number of high-risk HPV types was the predominant risk factor for abnormal anal cytology (OR 2.02, 95% CI 1.27-3.24). Infection with high-risk HPV was a significant predictor for cytological abnormality. MSM should be encouraged to obtain the HPV vaccine.

Large-scale genome-wide association study identifies HLA class II variants associated with chronic HBV infection: a study from Taiwan Biobank.

BACKGROUND: Chronic hepatitis B virus (HBV) infection is a great health burden with geographical variations. AIMS: To explore genetic variants associated with chronic HBV infection. METHODS: The study included 15 352 participants seropositive for HBV core antibodies in Taiwan Biobank. Among them, 2591 (16.9%) seropositive for HBV surface antigen (HBsAg) were defined as having chronic HBV infection. All participants were examined for whole-genome genotyping by Axiom-Taiwan Biobank Array. The human leucocyte antigen (HLA) imputation was performed after identification of the variants within the region. Logistic regressions were used to estimate odds ratios (ORs) with 95% confidence intervals. Correlations of different HLA allele frequencies with HBsAg seroprevalence were evaluated across worldwide populations by Pearson correlation coefficients. Epitope prediction was performed for HLA alleles using NetMHCIIpan method. RESULTS: Located within a cluster of 450 single nucleotide polymorphisms in HLA class II, rs7770370 (P = 2.73 × 10-35 ) was significantly associated with HBV chronicity (Pcorrected  < 8.6 × 10-8 ). Imputation analyses showed that HLA-DPA1*02:02 and HLA-DPB1*05:01 were associated with chronic HBV, with adjusted ORs of 1.43 (1.09-1.89) and 1.61 (1.29-2.01). These allele frequencies were positively correlated with global HBsAg seroprevalence, with R of 0.75 and 0.62 respectively (P < 0.05). HLA-DRB1*13:02, HLA-DQA1* 01:02 and HLA-DQB1*06:09 associated with HBV chronicity negatively, with adjusted ORs of 0.31 (0.17-0.58), 0.70 (0.56-0.87) and 0.33 (0.18-0.63). These HLA alleles had various binding affinities to the predicted epitopes derived from HBV nucleocapsid protein. CONCLUSIONS: HLA class II variants are relevant for chronicity after HBV acquisition.

Distribution of virulence genes in bacteremic methicillin-resistant Staphylococcus aureus isolates from various sources.

BACKGROUND/PURPOSE: Methicillin-resistant Staphylococcus aureus (MRSA) can encode proteins which directly bind bacteria to many tissues and medical devices or catheters to trigger pathogenesis. However, the relationship between genetic backgrounds and virulent factors in MRSA isolates remained incompletely understood yet. METHODS: MRSA isolates were collected from blood cultures of patients with infective endocarditis, bone/joint infection, skin/soft tissue infection, or catheter-related bacteremia in hemodialysis at a tertiary medical center between 2005 and 2011. MRSA isolates were characterized by the methods of spa, multilocus sequence, and staphylococcal cassette chromosome mec (SCCmec) typing. Identification of virulence gene expression was measured by Power SYBR Green PCR Master Mix. RESULTS: Overall collected were 136 MRSA bacteremic isolates, including those from the cases of infective endocarditis (n = 23), bone/joint infection (n = 49), skin/soft tissue infection (n = 20), or catheter-related bacteremia in patients with acute kidney injury or end-stage renal stage receiving hemodialysis (n = 54). CC8-ST239-MRSA-SCCmec type III-spa type t037 was the most prevalent type observed in all of 136 MRSA bacteremic isolates. The prevalent genes in the group of infective endocarditis were clfA, clfB, fnbA, ebpS, eap, emp, sae, and eno; bone/joint infections clfA, emp, sae, and eno; skin/soft tissue infection eno; hemodialysis catheter-related bacteremia clfA and sae. The distribution of each gene was not statically different among four groups. CONCLUSIONS: A major MRSA lineage, CC8-ST239-MRSA-SCCmec type III-spa type t037, is noted among bacteremic MRSA isolates. No disease-specific virulent genes can be identified.

Comparison of clinical characteristics of bacteremia from Elizabethkingia meningoseptica and other carbapenem-resistant, non-fermenting Gram-negative bacilli at a tertiary medical center.

BACKGROUND: Acquired carbapenem resistance among non-fermenting Gram-negative bacilli (NFGNB), such as Pseudomonas aeruginosa and Acinetobacter calcoaceticus-Acinetobacter baumannii complex (ACB complex), is a serious problem in nosocomial infections. We previously reported that patients infected with the intrinsically carbapenem-resistant Elizabethkingia meningoseptica were associated with high mortality. However, little information is available regarding the clinical outcome of E. meningoseptica bacteremia when compared to that of other carbapenem-resistant NFGNB. METHODS: We conducted an observational study that included consecutive patients with E. meningoseptica, carbapenem-resistant ACB complex, carbapenem-resistant P. aeruginosa, and Stenotrophomonas maltophilia bacteremia at a Taiwanese medical center in 2015. We compared the clinical characteristics and outcomes between patients with E. meningoseptica bacteremia and those with other carbapenem-resistant NFGNB bacteremia. RESULTS: We identified 30 patients with E. meningoseptica, 71 with carbapenem-resistant ACB complex, 25 with S. maltophilia, and 17 with carbapenem-resistant P. aeruginosa bacteremia. The clinical characteristics, disease severity, and previous antibiotic exposures were similar between patients with bacteremia either due to E. meningoseptica or other carbapenem-resistant NFGNB. Patients with E. meningoseptica bacteremia had a higher rate of appropriate empirical antibiotics than those with other carbapenem-resistant NFGNB and was less associated with central venous catheterization. The 28-day mortality rates were similar between patients with E. meningoseptica and the other carbapenem-resistant NFGNB bacteremia (46.7% vs 46%, p = 0.949). CONCLUSION: The mortality rate of E. meningoseptica bacteremia was as high as other carbapenem-resistant NFGNB infections. The emerging E. meningoseptica infection calls for active surveillance and continued awareness from clinical physicians for this serious carbapenem-resistant infection.

Incidence of and risk factors for cryptococcosis in kidney transplant recipients in Taiwan-A nationwide population-based study.

OBJECTIVES: The aim of this study was to determine the long-term incidence of cryptococcosis in kidney transplant recipients (KTRs) and to analyze its risk factors. METHODS: This retrospective population-based cohort study analyzed data obtained from Taiwan's National Health Insurance Research Database for KTRs during 2000-2012 and matched cohorts. Both populations were followed until death, development of cryptococcosis, or December 2013. RESULTS: A total of 4,933 KTRs and 49,930 matched patients were included. The cryptococcosis incidence rates for the KTR cohort and matched cohort were 10.59 and 0.4 per 10,000 person-years, respectively. The hazard ratio for cryptococcosis among KTRs was 26.65 (p<0.001); and 43.77 (p<0.001) for cryptococcosis affecting the central nervous system (CNS). The Kaplan-Meier method confirmed an elevated cumulative incidence of cryptococcosis among KTRs (1.00% vs. 0.04%). Predictors for cryptococcosis were advanced age (OR 1.39, 95% CI 1.02-1.89, P=0.038) and cancer (OR 2.63, 95% CI 1.22-5.67, P=0.013), but not the use of any particular class of immunosuppressants. CONCLUSIONS: KTRs are at dramatically higher risk of developing cryptococcosis, especially with CNS involvement, relative to a non-KTR matched cohort. Older KTRs and those with cancer are at even higher risk of developing cryptococcosis.

Resistance rates of non-albicans Candida infections in Taiwan after the revision of 2012 Clinical and Laboratory Standards Institute breakpoints.

PURPOSE: In 2012, the Clinical and Laboratory Standards Institute (CLSI) revised its breakpoints for drugs and species because of the increase in non-albicans Candida infections and their drug resistance. Following global trends, the non-albicans candidemia resistance rate has increased in Taiwan as well. To update the antifungal susceptibility of non-albicans candidemia isolates, we conducted a multicenter study using the revised break points. PATIENTS AND METHODS: Patients with non-albicans candidemia infections were identified at five tertiary hospitals in Taiwan from July 1, 2011, to June 30, 2014. The broth microdilution method using a Sensititre YeastOne system was performed for the determination of minimum inhibitory concentration (MIC). The susceptibility was interpreted based on the guidelines of the CLSI (CLSI M27-S4 and M27-S3). RESULTS: Candida tropicalis was the predominant non-albicans candidemia pathogen (42.4%), and it showed increased fluconazole non-susceptibility (36.3%) when compared to the results from previous studies. In particular, C. tropicalis showed high cross-resistance to azole agents. C. tropicalis isolates that were found to be resistant to fluconazole also showed increased resistance to voriconazole (82.2%) and posaconazole (100%). The increased non-susceptibility of Candida glabrata to multiple antifungal agents, based on the revised break points, resulted from an increase in dose-dependent susceptibility (94.4%) rather than from an increase in resistance (5.6%). CONCLUSION: The resistance rate of non-albicans candidemia isolates is increasing, particularly for C. tropicalis and C. glabrata.

High mortality among patients infected with hypervirulent antimicrobial-resistant capsular type K1 Klebsiella pneumoniae strains in Taiwan.

Capsular type K1 Klebsiella pneumoniae, highly virulent strains which are common in Asian countries, can cause pyogenic infections. These hypervirulent strains are usually susceptible to most antimicrobials, except for ampicillin. Little is known regarding the clinical and molecular characteristics of antimicrobial-resistant K1 K. pneumoniae strains. This retrospective study evaluated patients infected with capsular type K1 K. pneumoniae strains in a Taiwanese medical centre between April 2013 and March 2016. Antimicrobial-resistant strains were defined based on non-susceptibility to antimicrobial agents except ampicillin. We compared the clinical outcome of patients infected with and without antimicrobial-resistant strains. The in vivo virulence, genetic relatedness, and resistance mechanisms of these hypervirulent antimicrobial-resistant strains were also investigated. A total of 182 capsular type K1 K. pneumoniae strains were identified, including 18 antimicrobial-resistant strains. The 28-day mortality rate among the 18 cases caused by antimicrobial-resistant strains was significantly higher than that among 164 cases caused by antimicrobial-sensitive strains (50% vs. 10.4%, P < 0.001). Infection with antimicrobial-resistant strain independently increased the 28-day mortality risk. Most antimicrobial-resistant strains were not clonally related, and they exhibited high in vivo virulence in a mouse lethality experiment. The major resistance mechanisms involved the presence of ß-lactamases and the overexpression of efflux pumps. In conclusion, hypervirulent antimicrobial-resistant capsular type K1 K. pneumoniae strains can predispose to a fatal outcome. These strains may represent an emerging threat to public health in Taiwan.

Epidemiology and antifungal susceptibility of candidemia isolates of non-albicans Candida species from cancer patients.

Candidemia is a growing concern worldwide, and its species distribution has shifted toward non-albicans Candida in recent decades, especially in patients with malignancy. This study aimed to update the epidemiology and antifungal susceptibility of non-albicans candidemia isolates from the cancer patients. Adult cancer patients with non-albicans candidemia were recruited, and clinical data were retrospectively collected from five medical centers in Taiwan from 1 July 2011 to 30 June 2014. In vitro susceptibility was determined by the broth dilution method using a Sensititre YeastOne system and interpreted according to the guidelines of the Clinical and Laboratory Standards Institute. A total of 346 episodes of non-albicans candidemia were identified in cancer patients. Candida tropicalis was the most common species (n=145, 41.9%) and had the highest resistance rate to fluconazole (n=17, 13.9%) among all the preserved isolates, including C. tropicalis, Candida glabrata and Candida parapsilosis. A higher Charlson comorbidity index, non-albicans candidemia due to C. tropicalis, neutropenia and septic shock were independent predictors of 28-day mortality. In conclusion, the species distribution and antifungal susceptibility of non-albicans candidemia isolates in our study differed from those in Western countries, providing useful information about local epidemiology for the selection of empirical antifungal agents for cancer patients.

High minimum inhibitory concentration of imipenem as a predictor of fatal outcome in patients with carbapenem non-susceptible Klebsiella pneumoniae.

Carbapenem resistance in Klebsiella pneumoniae is important because of its increasing prevalence and limited therapeutic options. To investigate the clinical and microbiological characteristics of patients infected or colonized with carbapenem non-susceptible K. pneumoniae (CnsKP) in Taiwan, we conducted a retrospective study at Taipei Veterans General Hospital from January 2012 to November 2013. Carbapenem non-susceptibility was defined as a minimum inhibitory concentration (MIC) of ≥2 mg/L for imipenem or meropenem. A total of 105 cases with CnsKP were identified: 49 patients with infection and 56 patients with colonization. Thirty-one isolates had genes that encoded carbapenemases (29.5%), including K. pneumoniae carbapenemase (KPC)-2 (n = 27), KPC-3 (n = 1), VIM-1 (n = 1) and IMP-8 (n = 2). The in-hospital mortality among patients with CnsKP was 43.8%. A MIC for imipenem ≥16 µg/mL, nasogastric intubation and Acute Physiology and Chronic Health Evaluation II score were independent risk factors for in-hospital mortality for all patients with CnsKP. A MIC for imipenem ≥16 µg/mL was also an independent risk factor for 14-day mortality in patients with CnsKP. In conclusion, a positive culture for CnsKP was associated with high in-hospital mortality. A high imipenem MIC of CnsKP can predispose a patient to a poor prognosis.