Ojulong J, Mwambu T P, Joloba M, Bwanga F, Kaddu-Mulindwa D H
Department of Microbiology, Makerere University, Kampala, Uganda.
Tanzan J Health Res. 2009 Jul;11(3):149-53. doi: 10.4314/thrb.v11i3.47703.
Methicilline resistant Staphylococcus aureus (MRSA) strains are becoming increasingly multiresistant, and have recently developed resistance to vancomycin, which has been used successfully to treat MRSA for many years. In-vitro determination of resistance patterns of S. aureus is critical in terms of administering suitable antimicrobial treatments. The objective of this study was to determine the relative prevalence of MRSA among S. aureus isolates from surgical site infections and their antibiotic susceptibility pattern in Mulago Hospital, Kampala, Uganda. One hundred eighty eight pus swabs were collected from patients with surgical site infections. Swabs were inoculated for culture at the Microbiology Laboratory of the Faculty of Medicine, Makerere University. S. aureus isolates were identified using standard procedures and tested for oxacillin resistance according to methods of the National Committee for Clinical Laboratory Standards. Out of the 188 specimens, 54 (28.7%) grew S. aureus. Seventeen (31.5%) of the S. aureus isolates were confirmed as MRSA by PCR. Resistance rates of MRSA were 88.2% for trimethoprim-sulfamethoxazole, 88.2% for erythromycin, 58.8% for gentamycin, 70.6% for ciprofloxacin, and 88.2% for chloramphenicol. All isolates were found to be sensitive to vancomycin and clindamycin though the D-test was found to be positive in 82.4% of the isolates. In our region, although methicillin resistance increased in S. aureus strains, because of the unavailability and the high cost of alternative antibiotics, gentamycin is still suggested as an alternative for treatment of S. aureus infections. These results however indicate that vancomycin seemed to be the only antimicrobial agent effective against MRSA and it could be the drug of choice in treating multidrug resistant MRSA infection.
耐甲氧西林金黄色葡萄球菌（MRSA）菌株的多重耐药性日益增强，最近还对万古霉素产生了耐药性，而万古霉素多年来一直成功用于治疗MRSA。从体外确定金黄色葡萄球菌的耐药模式对于给予合适的抗菌治疗至关重要。本研究的目的是确定乌干达坎帕拉穆拉戈医院手术部位感染的金黄色葡萄球菌分离株中MRSA的相对流行率及其抗生素敏感性模式。从手术部位感染患者中收集了188份脓液拭子。拭子在马凯雷雷大学医学院微生物实验室接种培养。使用标准程序鉴定金黄色葡萄球菌分离株，并根据美国国家临床实验室标准委员会的方法检测对苯唑西林的耐药性。在188份标本中，54份（28.7%）培养出金黄色葡萄球菌。通过PCR确认17株（31.5%）金黄色葡萄球菌分离株为MRSA。MRSA对甲氧苄啶-磺胺甲恶唑的耐药率为88.2%，对红霉素为88.2%，对庆大霉素为58.8%，对环丙沙星为70.6%，对氯霉素为88.2%。尽管发现82.4%的分离株D试验呈阳性，但所有分离株对万古霉素和克林霉素均敏感。在我们地区，尽管金黄色葡萄球菌菌株中的耐甲氧西林性有所增加，但由于替代抗生素难以获得且成本高昂，仍建议将庆大霉素作为治疗金黄色葡萄球菌感染的替代药物。然而，这些结果表明万古霉素似乎是唯一对MRSA有效的抗菌药物，它可能是治疗多重耐药MRSA感染的首选药物。
