Uzunović Selma, Ibrahimagić Amir, Kamberović Farah, Kunarac Manja, Rijnders Michelle I A, Stobberingh Ellen E
1Department of Laboratory Diagnostics, Cantonal Public Health Institute of Zenica, 2Faculty of Health Care and Nursing, University "VITEZ" of Vitez; Bosnia and Herzegovina, 3Microbiology Department, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia, 4Department of Medical Microbiology, School for Public Health and Primary Care (CAPHRI), Maastricht University Medical Center, Mastricht, The Netherlands.
Med Glas (Zenica). 2013 Aug;10(2):217-24.
To investigate the iMLSB prevalence in 142 methicillin-sensitive (MSSA) and 48 methicillin-resistant (MRSA) in-patient (65), outpatient (75), and healthy carrier (150) Staphylococcus aureus isolates in Zenica-Doboj Canton, Bosnia and Herzegovina.
Disk diffusion testing by placing clindamycin (CLI) and erythromycin (ERY) disks 15 mm apart (edge to edge) on a Mueller-Hinton agar, as per CLSI guideline was performed. Two distinct induction phenotypes labelled as D and D+, and three noninduction phenotypes designated as Neg, R (constitutive, cMLSB), and S (susceptible). Methicillin-resistance was confirmed by the presence of mecA gene by PCR. The genetic characterization was performed using spa-typing and the algorithm based upon repeat patterns (BURP).
iMLSB was detected in six (2.1%) isolates, of which five (3.5%) (two outpatients and three carriers) were MSSA, and one (2.1%) (outpatient) MRSA. One of them, D+ phenotype (iMLSB) was obtained from a carrier (MSSA). None of the inpatients had iMLSB. HD phenotype was not detected. One (MRSA) isolate has shown negative phenotype. Two strains with iMLSB originated from skin and soft tissue (MRSA) and eye infection (MSSA) belonged to the same MLST CC8, with different spa-types (t451 and t008, respectively). R phenotype (cMLSB) was detected in two (inpatient) isolates (0.7%).
D test identified 2% of wrongly reported isolates as clindamycin sensitive. Despite low prevalence of S. aureus with iMLSB , it is a significant finding that they were mostly MSSA, and all were isolated from outpatients or carriers. D-test becomes an imperative part of routine antimicrobial susceptibility test for all S. aureus isolates.
调查波斯尼亚和黑塞哥维那泽尼察-多博伊州142株甲氧西林敏感（MSSA）和48株耐甲氧西林（MRSA）的住院患者（65例）、门诊患者（75例）及健康携带者（150例）金黄色葡萄球菌分离株中诱导型大环内酯类-林可酰胺类-链阳菌素B（iMLSB）的流行情况。
按照美国临床和实验室标准协会（CLSI）指南，在穆勒-欣顿琼脂上放置克林霉素（CLI）和红霉素（ERY）药敏纸片，使其边缘相距15 mm进行纸片扩散法检测。两种不同的诱导表型标记为D和D+，三种非诱导表型分别命名为阴性（Neg）、耐药（R，组成型，cMLSB）和敏感（S）。通过聚合酶链反应（PCR）检测mecA基因的存在来确认耐甲氧西林情况。使用葡萄球菌蛋白A分型（spa分型）和基于重复模式的算法（BURP）进行基因特征分析。
在6株（2.1%）分离株中检测到iMLSB，其中5株（3.5%）（2例门诊患者和3例携带者）为MSSA，1株（2.1%）（门诊患者）为MRSA。其中1株D+表型（iMLSB）分离自1名携带者（MSSA）。住院患者中未发现iMLSB。未检测到HD表型。1株（MRSA）分离株表现为阴性表型。2株携带iMLSB的菌株分别源自皮肤和软组织感染（MRSA）及眼部感染（MSSA），属于同一多位点序列分型（MLST）的CC8型，spa分型不同（分别为t451和t008）。在2株（住院患者）分离株（0.7%）中检测到R表型（cMLSB）。
D试验鉴定出2%报告错误的克林霉素敏感分离株。尽管携带iMLSB的金黄色葡萄球菌流行率较低，但一个重要发现是它们大多为MSSA，且均分离自门诊患者或携带者。D试验成为所有金黄色葡萄球菌分离株常规抗菌药物敏感性试验的必要组成部分。
