The impact of revised CLSI cefazolin breakpoints on the clinical outcomes of Escherichia coli bacteremia

AbstractBackground/PurposeThe susceptibility breakpoints of cephalosporins for Enterobacteriaceae were revised by the Clinical and Laboratory Standards Institute (CLSI) in 2010 and 2011. The clinical outcome and susceptibility data were analyzed to evaluate the impact of revised CLSI cefazolin breakpoints on the treatment of Escherichia coli bacteremia.MethodsForty-three bacteremic Escherichia coli isolates from Taichung Veterans General Hospital, Taichung, Taiwan, during the period from January 2013 to December 2013, were selected to analyze the minimum inhibitory concentration (MIC) distributions of cefazolin and the correlated clinical responses to cefazolin therapy.ResultsThe modal cefazolin MIC among the 43 isolates was 1 μg/mL and accounted for 18 (42%) isolates. The cumulative percentage for MICs ≤ 2 μg/mL was 79%. The conventional dosing regimens achieved clinical cure in 33 (97%) of 34 patients with bacteremia due to E. coli with a cefazolin MIC ≤ 2 μg/mL, in all of the six patients with a cefazolin MIC of 4 μg/mL, and all of the three patients with a cefazolin MIC of 8 μg/mL.ConclusionThe microbiological data support the revised CLSI breakpoints of cefazolin. The conventional cefazolin dosing regimens can still achieve satisfactory clinical cure rates for bacteremia of E. coli with a cefazolin MIC ≤ 2 μg/mL in patients without severe septic shock. Before the approval of the efficacy of cefazolin for the treatment of E. coli isolates with a cefazolin MIC of 4 μg/mL, it is prudent to use cefazolin only when a high drug level can be achieved in the infection site, such as the urinary tract

The association of molecular typing, vancomycin MIC, and clinical outcome for patients with methicillin-resistant Staphylococcus aureus infections

AbstractBackground/PurposeThere are reports of an increase in vancomycin minimum inhibitory concentration (MIC) against methicillin-resistant Staphylococcus aureus (MRSA) over time, a phenomenon referred to as “MIC creep”, but some studies have conflicting results. The aim of this study is to evaluate the association of molecular typing, vancomycin MIC, and clinical outcome for patients with MRSA infections.MethodsThirty-two MRSA isolates from Taichung Veterans General Hospital (TCVGH), Taichung, Taiwan during the period of 2003 to 2008 were analyzed for the association of sequence typing, vancomycin MIC, and the correlated clinical outcome for patients with MRSA infections. The vancomycin MICs of 28 additional isolates from 2014 were used for the detection of MIC creep.ResultsAmong the genotypes of 32 isolates, there were 17 (53.1%) isolates with ST239-SCCmecIII, seven (21.9%) isolates with ST5-SCCmecII, six (18.8%) isolates with ST59-SCCmecIV, and two (6.2%) isolates with ST59-SCCmecVT. Two isolates had an MIC of 2 μg/mL and were identified as ST239-SCCmecIII. No statistically significant change in the distribution of MICs of all isolates was observed between 2003 and 2014 (p = 0.263). There was no significant difference in the mortality rates between two groups of patients with vancomycin MICs < 2 μg/mL and ≥ 2 μg/mL (p = > 0.99).ConclusionThere was no vancomycin MIC creep in the period from 2003 to 2014 in this study. Appropriate prognostic models for assessment of the association among sequence types, vancomycin MICs, and clinical outcome warrant further investigation

Antimicrobial Susceptibility and Multiplex PCR Screening of AmpC Genes From Isolates of Enterobacter cloacae, Citrobacter freundii, and Serratia marcescens

Background/PurposeThe emergence of multiple drug resistance in Enterobacteriaceae is of particular concern. The aim of this study was to evaluate the antimicrobial susceptibility and screen for the ampC gene in three members of the Enterobacteriaceae family (Enterobacter cloacae, Citrobacter freundii, and Serratia marcescens) found at Taichung Veterans General Hospital during the past 5 years using multiplex polymerase chain reaction (PCR).MethodsThe susceptibility of thirty isolates from each of the three Enterobacteriaceae family members to five antimicrobial agents (ceftazidime, flomoxef, imipenem, moxifloxacin, and colistin) was assessed. The susceptibility was analyzed by disk diffusion, screening and confirmatory tests for extended-spectrum β-lactamases (ESBL) and minimum inhibitory concentration tests according to the recommendations of the Clinical and Laboratory Standards Institute. The detection of ampC genes (3 families, including DHA, EBC and CIT) was performed by multiplex PCR. To detect the coexistence of ESBL genes, PCR was performed using five primer pairs: TEM, SHV, SHV-5, CTX-M-3, and CTX-M-14.ResultsOf the 90 isolates, 53 (58.9%) were positive in the screening test for ESBL. Resistance genes were detected in 12 (22.6%) of these isolates: ampC gene of DHA type in one E. cloacae isolate and EBC type in three E. cloacae isolates; ampC gene of CIT type in four C. freundii isolates; CTX-M-3-like in one C. freundii isolate and one S. marcescens isolate; TEM in three E. cloacae isolates, three C. freundii isolates and two S. marcescens isolates; SHV in one C. freundii isolate.ConclusionAntibiotic phenotypes cannot accurately distinguish the resistance mechanisms caused by ampC or ESBL, and especially in ESBL-ampC combinations. However, PCR is a useful technique for the identification of the different types of resistance genes

Clinical Outcome of Mycobacterium abscessus Infection and Antimicrobial Susceptibility Testing

Background/PurposeMycobacterium abscessus is the most resistant and rapidly growing mycobacterium and causes a wide range of clinical infectious diseases. The relationship between antimicrobial susceptibility and clinical outcome needs to be further evaluated.MethodsForty M. abscessus isolates were obtained from clinical specimens of 40 patients at the Taichung Veterans General Hospital from January 2006 to December 2008. Antimicrobial susceptibility testing was performed using the broth microdilution method according to the recommendations of the National Committee for Clinical Laboratory Standards. The clinical manifestations and outcomes were reviewed from medical records.ResultsTwenty-two patients were diagnosed with M. abscessus infection. Cough (86.3%), hemoptysis (31.8%) and fever (18.1%) were the most common symptoms. The radiographic findings included reticulonodular opacities (50.0%), consolidation (31.8%) and cavitary lesions (18.1%). The 40 isolates were susceptible to amikacin (95.0%), cefoxitin (32.5%), ciprofloxacin (10.0%), clarithromycin (92.5%), doxycycline (7.5%), imipenem (12.5%), moxifloxacin (22.5%), sulfamethoxazole (7.5%) and tigecycline (100%). The rate of treatment failure was 27.3% at the end of the 12th month after the start of treatment, although these patients were treated with a combination of clarithromycin and other antimicrobial agents.ConclusionM. abscessus is naturally susceptible to clarithromycin and amikacin, variably susceptible to cefoxitin and imipenem, and resistant to most other antimicrobial drugs. Combination therapy with clarithromycin, amikacin and other active antimicrobial agents may lead to clinical improvement; however, the rate of treatment failure is still high

Epidemiology of methecillin resistant Staphylococcus aureus isolates in Taiwan

摘 要 金黃色葡萄球菌(Staphylococcus aureus)是醫院最常見的致病菌，自從1961年分離出第一株抗甲氧苯青黴素金黃色葡萄球菌（methecillin resistant Staphylococcus aureus;MRSA）之後，MRSA很快的出現在各國，由於抗生素的大量使用，使MRSA成為目前院內感染最常見的菌種。本研究收集台灣地區5家醫院自2001年1月至2008年3月共107株MRSA，期望藉脈衝電場電泳基因分型法（Pulsed-field gel electrophoresis；PFGE）、多基因組序列分析(Multilocuse sequence typing；MLST)兩種方法，分析菌株的基因相關性，並進一步和其他國家比較，找出台灣的本土流行株，並比較台灣不同地域MRSA的親源相關性。脈衝電場電泳結果，經比對分析菌株親緣樹枝圖後，親緣百分比>80％即定義為同一族群(cluster)，因此得到五種族群：A（80.5％）、B（89.8％）、C（80.4％）、D（88.0％）與E（87.5％），其中A群與B群全台5家醫院都存在此兩群，C、D、E群則各分布在不同醫院。本次107株MRSA經MLST分型再與資料庫比對，共87株可比對，且有6種型別，包括：ST239、ST59、ST241、ST5、ST25與ST221，最主要的是ST239與ST59，各佔59.8％與13％。從本研究發現ST239是臺灣最主要的流行株，與亞洲國家有些異同，如韓國主要的流行株是ST5與ST239，而日本主要的流行株是ST5，又中國的主要菌株是ST239，和台灣具相同的流行株，原因可能是中國和台灣經常有台商和探親來往頻繁之故。另一方面，本研究呈現MRSA在臺灣的醫院是廣泛分佈的，所以醫院對於此抗藥性菌株，除了持續的監測，完備的感控措施及完善的抗生素管制外，嚴謹的院內感染管制政策的落實，是最重要的預防院內感染（nosocomial infection）之道。目 次 誌謝--------------------------------------------------------------- i 中文摘要----------------------------------------------------------- ii 英文摘要-------------------------------------------------------- iii 目次------------------------------------------------------------------------- iv 圖表次----------------------------------------------------------------------- v 壹、前言-------------------------------------------------------------------- 1 貳、材 料 與 方 法 一、菌株來源-------------------------------------------------------------- 6 二、藥品-------------------------------------------------------------------- 7 三、培養基----------------------------------------------------------------- 7 四、抗生素----------------------------------------------------------------- 8 五、細菌之培養與鑑定-------------------------------------------------- 8 六、最低抑菌濃度-------------------------------------------------------- 11 七、脈衝電場電泳法----------------------------------------------------- 12 八、PFGE條紋片段的比對---------------------------------------------- 14 九、DNA萃取--------------------------------------------------------------- 15 十、進行MLST前的PCR反應------------------------------------------- 15 十一、多基因定序分型-------------------------------------------------- 16 十二、mecA測定---------------------------------------------------------- 17 叁、結果 一、細菌鑑定-------------------------------------------------------------- 18 二、最低抑菌濃度-------------------------------------------------------- 18 三、PCR反應--------------------------------------------------------------- 19 四、脈衝電場電泳-------------------------------------------------------- 19 五、多基因定序分型----------------------------------------------------- 20 肆、討論-------------------------------------------------------------------- 21 伍、結論-------------------------------------------------------------------- 27 陸、參考文獻-------------------------------------------------------------- 48 柒、附錄-------------------------------------------------------------------------------- 63 圖 表 次 表一金黃色葡萄球菌對oxacillin的最低抑菌濃度結果-------- 30 表二、MLST PCR引子的序列------------------------------------------ 31 表三、MLST基因型的表現--------------------------------------- 32 表四、台灣地區醫院ST的分布--------------------------------------- 33 表五、臺灣地區PFGE型別的分佈------------------------------------ 34 圖一、金黃色葡萄球菌在血液培養基的菌落型態----------------- 35 圖二、革蘭氏染色結果-------------------------------------------------- 36 圖三、tpi、gmk與pta為引子的PCR產物--------------------------- 37 圖四、mecA為引子的PCR產物--------------------------------------- 38 圖五、MRSA的脈衝電場電泳結果------------------------------------- 39 圖六、107株MRSA的PFGE結果親緣樹枝圖------------------------ 40 圖七、中榮MRSA的PFGE結果親緣樹枝圖------------------------ 41 圖八、馬偕MRSA的PFGE結果親緣樹枝圖-------------------------- 42 圖九、桃園MRSA的PFGE結果親緣樹枝--------------------------- 43 圖十、屏東MRSA的PFGE結果親緣樹枝圖------------------------ 44 圖十一、高雄MRSA的PFGE結果親緣樹枝圖-------------------- 45 圖十二、ST59的PFGE結果親緣樹枝圖------------------------------ 46 圖十三、ST239的PFGE結果親緣樹枝圖---------------------------- 4

The association of molecular typing, vancomycin MIC, and clinical outcome for patients with methicillin-resistant Staphylococcus aureus infections

Background/Purpose: There are reports of an increase in vancomycin minimum inhibitory concentration (MIC) against methicillin-resistant Staphylococcus aureus (MRSA) over time, a phenomenon referred to as “MIC creep”, but some studies have conflicting results. The aim of this study is to evaluate the association of molecular typing, vancomycin MIC, and clinical outcome for patients with MRSA infections. Methods: Thirty-two MRSA isolates from Taichung Veterans General Hospital (TCVGH), Taichung, Taiwan during the period of 2003 to 2008 were analyzed for the association of sequence typing, vancomycin MIC, and the correlated clinical outcome for patients with MRSA infections. The vancomycin MICs of 28 additional isolates from 2014 were used for the detection of MIC creep. Results: Among the genotypes of 32 isolates, there were 17 (53.1%) isolates with ST239-SCCmecIII, seven (21.9%) isolates with ST5-SCCmecII, six (18.8%) isolates with ST59-SCCmecIV, and two (6.2%) isolates with ST59-SCCmecVT. Two isolates had an MIC of 2 μg/mL and were identified as ST239-SCCmecIII. No statistically significant change in the distribution of MICs of all isolates was observed between 2003 and 2014 (p = 0.263). There was no significant difference in the mortality rates between two groups of patients with vancomycin MICs  0.99). Conclusion: There was no vancomycin MIC creep in the period from 2003 to 2014 in this study. Appropriate prognostic models for assessment of the association among sequence types, vancomycin MICs, and clinical outcome warrant further investigation

Biofeedback relaxation for pain associated with continuous passive motion in Taiwanese patients after total knee arthroplasty

[[abstract]]Effective pain management is crucial for patient recovery after total knee arthroplasty (TKA). Biofeedback therapy, which encourages relaxation and helps alleviate various conditions associated with stress, may help to decrease postoperative pain in patients undergoing TKA. A quasi- experimental design was used to investigate the efficacy of a biofeedback relaxation intervention in reducing pain associated with postoperative continuous passive motion (CPM) therapy. Sixty-six patients admitted to a general hospital in Taiwan for TKA were recruited and randomly assigned to the intervention or control group. The intervention group received biofeedback training twice daily for 5 days, concurrent with CPM therapy, whereas the control group did not receive the biofeedback intervention. Pain was measured using a numeric rating scale before and after each CPM therapy session on postoperative days 1 through 5. The CPM-elicited pain score was calculated by subtracting the pre-CPM pain score from the post-CPM pain score. Results of repeated-measures analysis of variance showed intervention group reported significantly less pain caused by CPM than did the control group (f = 29.70, p < 0.001). The study results provide preliminary support for biofeedback relaxation, a non-invasive and non-pharmacological intervention, as a complementary treatment option for pain management in this population