Dekker Denise, Wolters Manuel, Mertens Eva, Boahen Kennedy Gyau, Krumkamp Ralf, Eibach Daniel, Schwarz Norbert G, Adu-Sarkodie Yaw, Rohde Holger, Christner Martin, Marks Florian, Sarpong Nimako, May Jürgen
Bernhard Nocht Institute for Tropical Medicine (BNITM), Research Group Infectious Disease Epidemiology, Bernhard-Nocht-Str. 74, D-20359, Hamburg, Germany.
German Centre for Infection Research (DZIF), Hamburg-Borstel-Lübeck, Hamburg, Germany.
BMC Infect Dis. 2016 Nov 29;16(1):720. doi: 10.1186/s12879-016-2048-3.
Staphylococcus aureus is among the most common pathogens isolated from blood cultures in Ghana; yet the epidemiology of blood infections in rural settings is poorly described. This study aims to investigate antimicrobial susceptibility and clonal diversity of S. aureus causing bloodstream infections in two hospitals in the Ashanti Region, Ghana.
Blood cultures were performed for all febrile patients (≥37.5 °C) on hospital admission. Antibiotic susceptibility testing for S. aureus isolates was carried out by the VITEK 2 system. Multiplex polymerase chain reaction (PCR) was used to detect S. aureus-specific nuc gene, Panton-Valentine leukocidin (PVL), and methicillin-resistant S. aureus (MRSA)-specific mecA and mecC genes. The population structure of S. aureus was assessed by spa typing.
In total, 9,834 blood samples were cultured, out of which 0.6% (n = 56) were positive for S. aureus. Multidrug resistance (MDR) was detected in 35.7% (n = 20) of the S. aureus strains, of which one was a MRSA. The highest rate of antibiotic resistance was seen for commonly available antibiotics, including penicillin (n = 55; 98.2%), tetracycline (n = 32; 57.1%) and trimethoprim/sulfamethoxazole (n = 26; 46.4%). Of all S. aureus strains, 75.0% (n = 42) carried the PVL-encoding genes. We found 25 different spa types with t355 (n = 11; 19.6%), t314 (n = 8; 14.3%), t084 (n = 8; 14.3%) and t311 (n = 5; 8.9%) being predominant.
The study exhibited an alarmingly large level of antibiotic resistance to locally available antibiotics. The frequency of genetically diverse and PVL-positive methicillin-sensitive S. aureus (MSSA) was high and could represent a reservoir for the emergence of virulent PVL-positive MRSA clones.
金黄色葡萄球菌是加纳血培养中分离出的最常见病原体之一；然而，农村地区血液感染的流行病学情况描述甚少。本研究旨在调查加纳阿散蒂地区两家医院中引起血流感染的金黄色葡萄球菌的抗菌药敏性和克隆多样性。
对所有入院时发热（≥37.5°C）的患者进行血培养。金黄色葡萄球菌分离株的抗生素药敏试验通过VITEK 2系统进行。采用多重聚合酶链反应（PCR）检测金黄色葡萄球菌特异性nuc基因、杀白细胞素（PVL）以及耐甲氧西林金黄色葡萄球菌（MRSA）特异性mecA和mecC基因。通过spa分型评估金黄色葡萄球菌的群体结构。
共培养了9834份血样，其中0.6%（n = 56）金黄色葡萄球菌呈阳性。在35.7%（n = 20）的金黄色葡萄球菌菌株中检测到多重耐药（MDR），其中1株为MRSA。常见抗生素的耐药率最高，包括青霉素（n = 55；98.2%）、四环素（n = 32；57.1%）和甲氧苄啶/磺胺甲恶唑（n = 26；46.4%）。在所有金黄色葡萄球菌菌株中，75.0%（n = 42）携带编码PVL的基因。我们发现了25种不同的spa型，其中t355（n = 11；19.6%）、t314（n = 8；14.3%）、t084（n = 8；14.3%）和t311（n = 5；8.9%）占主导。
该研究显示对当地可用抗生素的耐药水平高得惊人。基因多样且PVL阳性的甲氧西林敏感金黄色葡萄球菌（MSSA）频率很高，可能是毒性PVL阳性MRSA克隆出现的一个来源。
