白内障手術前患者における通常培養による結膜囊内細菌検査

Bacterial flora in the conjunctival sac in eyes before cataract surgery cultured as routine procedure

要約　目的：白内障手術前患者を対象として通常の好気性培養にて結膜囊内常在菌を検索した報告。対象：569眼中305眼（53.6％）に細菌が検出され，総菌株数は435株であった。結果：80歳以上の高齢者群では65歳未満，65歳以上80歳未満の群と比べて菌検出率が有意に高かった。糖尿病およびアトピー性皮膚炎の既往の有無による比較では菌検出率，検出菌の内訳ともに差を認めなかった。メチシリン耐性表皮ぶどう球菌（MRSE）は65株であり，そのうちレボフロキサシン（LVFX）耐性菌は53株（81.5％）であった。メチシリン耐性黄色ブドウ球菌（MRSA）5株のうち，LVFX耐性菌は3株（60.0％）であった。MRSEおよびMRSAのレボフロキサシン耐性率は，それぞれのメチシリン感受性菌と比べて有意に高かった。結論：高齢者ほど細菌，特に薬剤耐性菌が検出されやすく，術前の一律なLVFX点眼には限界があり，術前結膜囊内細菌検査を行うことは，術後感染症の予防および治療のために有意義と考えられた。

Abstract.　Purpose：To report bacterial flora in the conjunctival sac in eyes before cataract surgery cultured by routine aerobic method. Cases：This study was made on 567 eyes of 434 patients prior to cataract surgery. The series comprised 256 male and 313 female eyes. The age averaged 73 years. Results：Bacterial organism was cultured in 305 out of 569 eyes（53.6％）and totaled 435 strains. Rate of positive culture was significantly higher in cases aged 80 years or over than in those between 65 and 80 years and those under 60 years of age. Presence of diabetes mellitus or atopic dermatitis did not influence the rate of positive culture or the nature of strains. There were 65 cases of methicillin-resistant Staphylococcus epidermidis（MRSE）. Out of 5 strains methicillin-resistant Streptococcus aureus（MRSA）, there were 3 strains resistant to levofloxiacin（LVFX）. Strains of MRSE and MRSA showed significantly higher rate of resistance to LVFX than those sensitive to methicillin. Conclusion：Persons in higher age group showed higher rates of bacterial flora including those resistant to antibiotics. This finding shows limited value of LVFX instillation prior to cataract surgery and shows the importance of culture of bacterial organisms in preventing infection after surgery.