貝華鋒+茅國峰
[摘要] 目的 探討本院近三年糞腸球菌臨床分布及耐藥性特征,為臨床用藥提供參考。 方法 選取近三年臨床分離出的糞腸球菌239株,分析其臨床分布特征,并做常規抗生素敏感性試驗,用whonet5.4軟件進行統計學分析。結果 糞腸球菌大多來源于肝膽外科、泌尿外科的尿液、膽汁和引流液標本;對喹努普汀/達福普汀耐藥率為100%,對四環素和紅霉素耐藥率均為53.14%,呋喃妥因對糞腸球菌敏感性較高,為95.82%;糞腸球菌對替加環素、替考拉寧和萬古霉素全敏感。結論 加強藥敏試驗,定期監測臨床耐藥現象,對指導臨床用藥具有重要意義。
[關鍵詞] 糞腸球菌;耐藥性;抗生素;藥敏試驗
[中圖分類號] R446.5 [文獻標識碼] B [文章編號] 1673-9701(2014)28-0063-03
腸球菌屬為條件致病性菌,可造成人體多種組織器官感染,為人體腸道內正常寄生菌群,異味寄生可引起呼吸道、泌尿道及敗血癥等一系列感染病癥。近年來發現腸球菌引起的院內感染現象日益嚴重,且對常規藥物耐藥性日益嚴重,其中最常見的為糞腸球菌[1,2],容易被忽視,為了解本院糞腸球菌感染情況及耐藥率,選取近三年來臨床分離的糞腸球菌為研究對象,分析其臨床分布及感染情況,同時監測其對各種常見抗生素耐藥率及敏感性,為臨床醫師選擇抗生素做參考。
1 材料與方法
1.1 標本來源
收集中醫院2010~2013年三年臨床科室分離的239株糞腸球菌,操作規程按衛生部標準進行。
1.2 分析方法
采用法國全自動梅里埃微生物鑒定儀分離鑒定菌株,紙片擴散法(K-B法)進行藥敏實驗,根據CLSI規定的標準判定結果[3]。
1.3 藥敏紙片
藥敏紙片為喹努普汀/達福普汀、四環素、紅霉素、高水平慶大霉素、高水平鏈霉素、氨芐西林、青霉素G、環丙沙星、左旋氧氟沙星、莫西沙星、呋喃妥因、替加環素、替考拉寧和萬古霉素。
1.4 統計學處理
Whonet5.4軟件進行統計學分析。
2 結果
2.1 標本來源
本院分離的239株糞腸球菌主要取自膽汁、尿液及引流液中,占80%以上,其中尿液97例,膽汁86例,見表1。
2.2 科室分布
肝膽外科和泌尿外科分別分離出糞腸球菌108株和63株,占大多數,其余各科室分離菌落數較少,見表2 。
2.3 藥敏試驗
藥敏結果顯示糞腸球菌對喹努普汀/達福普汀耐藥率為100%,對四環素和紅霉素耐藥率均為53.14%,呋喃妥因對糞腸球菌敏感性較高,為95.82;對青霉素G、氨芐西林和莫西沙星等敏感性亦較高,為80%左右,糞腸球菌對替加環素、替考拉寧和萬古霉素全敏感(表3)。
3 討論
腸球菌存在于人及動物腸道內,屬于正常菌群,最初在腸道及盆腔感染中被發現,在院內感染致病菌中僅次于葡萄球菌。腸球菌能夠引起一系列感染病灶,如泌尿系統感染、呼吸系統感染及敗血癥等感染癥狀。其中最重要的代表是糞腸球菌,屬于條件致病菌。近幾年來,由于應用侵入性治療,免疫抑制劑的廣泛使用以及不合理應用抗菌藥物等若干原因,導致糞腸球菌耐藥現象日益嚴峻,應受到臨床重視。
本文對臨床分離出的239株糞腸球菌統計分析表明,糞腸球菌大多數來自于膽汁、尿液及引流液等標本中。據報道院內尿路感染中大腸桿菌居首,腸球菌以16%的比例位居第二,導致這種現象的原因主要與導尿管的留置、醫療器械的操作以及異常的尿路結構相關,如腎盂腎炎及膀胱炎等,也有少數為腎周膿腫[4,5]。與廖國林等[6]報道結果一致,但與劉媚娜等[7]結果具有一定差異,這與醫院的科室結構、床位配置、病種構成、標本來源等不同有關。對于本院而言,肝膽外科和泌尿外科分別分離出糞腸球菌108株和63株,占大多數。
近年來由于免疫抑制劑和廣譜抗菌藥物使用,出現了耐高濃度氨基糖苷類藥物腸球菌屬(HLAR)[8-10]和耐萬古霉素腸球菌(VRE)[11,12]。氨基糖苷類抗生素對于細菌的作用主要是抑制細菌蛋白質的合成,研究表明,氨基糖苷類抗生素妨礙初始復合物的合成,通過影響細菌蛋白質合成全過程,誘導細菌合成錯誤蛋白以及阻抑已合成蛋白的釋放,從而導致細菌死亡。耐高濃度氨基糖苷類藥物腸球菌屬產生的質粒介導的氨基糖苷類修飾酶[如乙酰轉移酶(AAC)、磷酸轉移酶(APH)、核苷轉移酶(ANT)]使氨基糖苷類抗菌藥物氨基乙酰化、羥基磷酸化和羥基核苷化,不能再與細菌核糖體結合,使得該類細菌與細胞壁合成藥物的聯合用藥的協同作用消失[13-16]。本院糞腸球菌藥敏結果顯示糞腸球菌對喹努普汀/達福普汀耐藥率為100%,對四環素和紅霉素耐藥率均為53.14%。相關文獻[17-19]研究表明腸球菌對青霉素敏感性較差,主要機制為細菌產生一種特殊的青霉素結合蛋白(PBP5),后者與青霉素的親和力減低,從而導致耐藥[20,21],本研究顯示糞腸球菌對青霉素G敏感性亦較高,提示本院尚未出現較高的青霉素耐藥糞腸球菌,腸球菌屬通常存在于人體腸道和女性生殖道中,而且常常存在于環境中,這類細菌可造成感染。萬古霉素常常作為治療腸球菌屬感染的最后有效抗菌藥物,某些情況下,腸球菌屬對萬古霉素產生耐藥,這類細菌稱為耐萬古霉素腸球菌(VRE),大多數的VRE感染通常發生在醫院內[22,23]。本院糞腸球菌對氨基糖苷類藥物慶大霉素和鏈霉素耐藥率亦較低,敏感性為萬古霉素100%,尚未出現耐萬古霉素腸球菌(VRE)菌株,表明腸球菌中糞腸球菌耐藥性普遍較屎腸球菌緩和,與相關文獻報道一致[22,23],但臨床必須嚴格按照實驗室檢測的耐藥情況進行用藥,防止耐藥現象加重。
從本文糞腸球菌耐藥分析得出,目前我院分離的糞腸球菌耐藥現象控制較好,常用藥物亦具有較強的抗菌作用。臨床上應對產菌株進行監測,臨床醫師應避免經驗用藥,要通過耐藥性檢測和藥敏試驗為其提供合理選擇抗生素治療的直接依據,以達到增加治愈率,減少耐藥率的目的,控制耐藥菌株的播散和流行。endprint
[參考文獻]
[1] Arias CA,Murray BE. The rise of the Enterococcus:beyond vancomycin resistance[J]. Nat Rev Microbiol,2012,10(4):266-278.
[2] 胡志東,王金良. 腸球菌耐藥性的研究進展[J]. 國際流行病學傳染病學志,2007,34(4):284.
[3] 郭玲嬌,李招云,張穎,等. 鮑氏不動桿菌感染及耐藥性分析[J]. 中華醫院感染學雜志,2007,17(2):216-217.
[4] Matsumoto T,Hamasuna R,Ishikawa K,et al. Sensitivities of major causative organisms isolated from patients with acute uncomplicated cystitis against various antibacterial agents:results of subanalysis based on the presence of menopause[J]. J Infect Chemother,2012,18(4):597-607.
[5] Cai T,Mazzoli S,Mondaini N,et al. The role of asymptomatic bacteriuria in young women with recurrent urinary tract infections:to treat or not to treat?[J]. Clin Infect Dis,2012,55(6):771-777.
[6] 廖國林,劉建,李芳,等. 腸球菌屬醫院感染分布及耐藥性分析[J]. 中華醫院感染學雜志,2009,19(13):1735-1736.
[7] 劉媚娜,程水兵,徐春泉,等. 屎腸球菌和糞腸球菌的耐藥性分析[J]. 中國衛生檢驗雜志,2010,20(5):1165-1166.
[8] Kozuszko S,Bialucha A,Bogiel T,et al. High level of aminoglycoside resistanceamong Enterococcus faecalis and Enterococcusfaecium strains[J]. Med Dosw Mikrobiol,2011, 63(2):105-113.
[9] Sibel AK,Koroglu M,Muharrem AK. The evaluation of antimicrobial susceptibility of urine enterococci with the Vitek 2 automated system in eastern Turkey[J]. Southeast Asian J Trop Med Public Health,2012,43(4):986-991.
[10] Aleksandrowicz. The incidence of high-level aminoglicoside and high-level beta-lactam resistance among enterococcal strains of various origin[J]. Med Dosw Mikrobiol,2012,64(1):11-18.
[11] Linden PK. Optimizing therapy for vancomycin-resistant enterococci(VRE)[J]. Semin Respir Crit Care Med,2007,28(6):632-645.
[12] Anderson NW,Buchan BW,Young CL,et al. Multicenter clinical evaluation of VRE select agar for identification of vancomycin-resistant Enterococcus faecalisand Enterococcus faecium[J]. J Clin Microbiol,2013,51(8):2758-2760.
[13] Parameswarappa J,Basavaraj VP,Basavaraj CM. Isolation,identification,and antibiogram of enterococci isolated from patients with urinary tract infection[J]. Ann Afr Med,2013,12(3):176-181.
[14] Thakuria B,Lahon K. The beta lactam antibiotics as an empirical therapy in a developing country:an update on their current status and recommendations to counter the resistance against them[J]. J Clin Diagn Res,2013,7(6):1207-1214.
[15] Czogala W,Gozdzik J,Czogala M,et al. Evaluation of colonization by multidrug-resistant organisms and infections' frequency in chronically and incurably ill children under care of the Cracow Children's Hospice of Father J. Tischner[J]. Przegl Lek,2010,67(1):40-44.endprint
[16] Mendiratta DK,Kaur H,Deotale V,et al. Status of high level aminoglycoside resistant Enterococcus faecium and Enterococcus faecalis in a rural hospital of central India[J]. Indian J Med Microbiol,2008,26(4):369-371.
[17] Cercenado E. Enterococcus:phenotype and genotype resistance and epidemiology in Spain[J]. Enferm Infecc Microbiol Clin,2011,29(5):59-65.
[18] Schwaiger K,Bauer J,Hormansdorfer S,et al. Presence of the resistance genes vanC1 and pbp5 in phenotypically vancomycin and ampicillin susceptible Enterococcus faecalis[J]. Microb Drug Resist,2012,18(4):434-439.
[19] Hanchi H,Hammami R,Kourda R,et al. Bacteriocinogenic properties and in vitro probiotic potential of Enterococci from Tunisian dairy products[J]. Arch Microbiol, 2014,196(5):331-344.
[20] Leimanis S,Hoyez N,Hubert S,et al. PBP5 complementation of a PBP3 deficiency in Enterococcus hirae[J]. J Bacteriol,2006,188(17):6298-6307.
[21] López M,Tenorio C,Del Campo R. Characterization of the mechanisms of fluoroquinolone resistance in vancomycin-resistant Enterococci of different origins[J]. J Chemother,2011,23(2):87-91.
[22] Eerdunbayaer EY,Orabi MA,Aoyama H,et al. Structures of two new flavonoids and effects of licorice phenolics on vancomycin-resistantent Enterococcus species[J]. Mole-cules,2014,19(4):3883-3897.
[23] Jovanovic M,Milosevic B,Dulovic O,et al. Molecular characterization of vancomycin-resistant Enterococci in Serbia:intensive care unit as the source[J]. Acta Microbiol Immunol Hung,2013,60(4):433-446.
(收稿日期:2014-03-11)endprint
[16] Mendiratta DK,Kaur H,Deotale V,et al. Status of high level aminoglycoside resistant Enterococcus faecium and Enterococcus faecalis in a rural hospital of central India[J]. Indian J Med Microbiol,2008,26(4):369-371.
[17] Cercenado E. Enterococcus:phenotype and genotype resistance and epidemiology in Spain[J]. Enferm Infecc Microbiol Clin,2011,29(5):59-65.
[18] Schwaiger K,Bauer J,Hormansdorfer S,et al. Presence of the resistance genes vanC1 and pbp5 in phenotypically vancomycin and ampicillin susceptible Enterococcus faecalis[J]. Microb Drug Resist,2012,18(4):434-439.
[19] Hanchi H,Hammami R,Kourda R,et al. Bacteriocinogenic properties and in vitro probiotic potential of Enterococci from Tunisian dairy products[J]. Arch Microbiol, 2014,196(5):331-344.
[20] Leimanis S,Hoyez N,Hubert S,et al. PBP5 complementation of a PBP3 deficiency in Enterococcus hirae[J]. J Bacteriol,2006,188(17):6298-6307.
[21] López M,Tenorio C,Del Campo R. Characterization of the mechanisms of fluoroquinolone resistance in vancomycin-resistant Enterococci of different origins[J]. J Chemother,2011,23(2):87-91.
[22] Eerdunbayaer EY,Orabi MA,Aoyama H,et al. Structures of two new flavonoids and effects of licorice phenolics on vancomycin-resistantent Enterococcus species[J]. Mole-cules,2014,19(4):3883-3897.
[23] Jovanovic M,Milosevic B,Dulovic O,et al. Molecular characterization of vancomycin-resistant Enterococci in Serbia:intensive care unit as the source[J]. Acta Microbiol Immunol Hung,2013,60(4):433-446.
(收稿日期:2014-03-11)endprint
[16] Mendiratta DK,Kaur H,Deotale V,et al. Status of high level aminoglycoside resistant Enterococcus faecium and Enterococcus faecalis in a rural hospital of central India[J]. Indian J Med Microbiol,2008,26(4):369-371.
[17] Cercenado E. Enterococcus:phenotype and genotype resistance and epidemiology in Spain[J]. Enferm Infecc Microbiol Clin,2011,29(5):59-65.
[18] Schwaiger K,Bauer J,Hormansdorfer S,et al. Presence of the resistance genes vanC1 and pbp5 in phenotypically vancomycin and ampicillin susceptible Enterococcus faecalis[J]. Microb Drug Resist,2012,18(4):434-439.
[19] Hanchi H,Hammami R,Kourda R,et al. Bacteriocinogenic properties and in vitro probiotic potential of Enterococci from Tunisian dairy products[J]. Arch Microbiol, 2014,196(5):331-344.
[20] Leimanis S,Hoyez N,Hubert S,et al. PBP5 complementation of a PBP3 deficiency in Enterococcus hirae[J]. J Bacteriol,2006,188(17):6298-6307.
[21] López M,Tenorio C,Del Campo R. Characterization of the mechanisms of fluoroquinolone resistance in vancomycin-resistant Enterococci of different origins[J]. J Chemother,2011,23(2):87-91.
[22] Eerdunbayaer EY,Orabi MA,Aoyama H,et al. Structures of two new flavonoids and effects of licorice phenolics on vancomycin-resistantent Enterococcus species[J]. Mole-cules,2014,19(4):3883-3897.
[23] Jovanovic M,Milosevic B,Dulovic O,et al. Molecular characterization of vancomycin-resistant Enterococci in Serbia:intensive care unit as the source[J]. Acta Microbiol Immunol Hung,2013,60(4):433-446.
(收稿日期:2014-03-11)endprint