Antimicrobial resistance in Enterococcus faecalis from fishes

Abstract

Enterococci, which are found as commensal in animals and human, can cause infections in definite conditions. The improvement and increment of aquaculture cause to happen a big problem for not only the other bacterial infections but also enterococcal infections in fishes. Enterococci are interesting microorganisms owing the wide range of distribution in nature, high level of antimicrobial resistance, and high mortality rates in enterococcal infections. The aim of this study was to determine the resistance to vancomycin and other antimicrobials in fish isolates of enterococci. Twenty six Enterococcus faecalis strains which were isolated in sick and dead fishes were used in study. Ciprofloxacin, erythromycin, tetracycline, streptomycin, ampicillin, gentamicin, penicillin, and vancomycin susceptibility of E.faecalis strains were examined with agar disc diffusion techniques. The vancomycin resistance phenotype of vancomycin resistant enterococci (VRE) was determined by agar dilution method. Ciprofloxacin, erythromycin, tetracycline, streptomycin, ampicillin, gentamicin, penicillin and vancomycin resistance of E.faecalis strains were found as 34.6%, 3.8%, 3.8%, 96.1%, 11.5%, 92.3%, 11.5%, and 3.8%, respectively. One of the 26 E.faecalis strains (3.8%) was found as vancomycin resistant (VRE) and the vancomycin resistance phenotype of this strain was determined as VanA. These findings showed that ciprofloxacin, streptomycin and gentamicin resistant E.faecalis strains were prevalent in fishes. Despite of the low proportion, the presence of a vancomycin resistant E.faecalis strain suggested that fishes must be considered as VRE source

Keywords

• Antimicrobial resistance
• Enterococcus faecalis
• fish
• vancomycin

Balık kökenli Enterococcus faecalis suşlarının antibiyotik dirençlilikleri

Abstract

İnsan ve hayvanlarda komensal olarak bulunan enterokoklar, belirli koşullarda hastalıklara neden olabilirler. Kültür balıkçılığının gelişmesi ve artması ile balıklarda diğer bakteriyel infeksiyonlarla birlikte enterokokkal infeksiyonlar da büyük bir problem olmaya başlamışlardır. Enterokoklar, doğadaki geniş dağılımları, yüksek düzeyde antibiyotik dirençlilikleri ve neden oldukları infeksiyonlardaki yüksek mortaliteleri ile ilgi çeken mikroorganizmalardır. Bu çalışmada, balıklardan izole edilen Enterokokların vankomisin ve diğer antibiyotiklere karşı dirençliliklerinin belirlenmesi amaçlandı. Çalışmamızda Ege Bölgesinde hasta ve ölü balıklardan izole edilen 26 Enterococcus faecalis suşu kullanıldı. E. faecalis suşlarının siprofloksasin, eritromisin, tetrasiklin, streptomisin, ampisilin, gentamisin, penisilin ve vankomisin duyarlılıkları agar-disk difüzyon tekniği ile incelendi. Vankomisin dirençli enterokokların (VRE) vankomisin direnç fenotipleri agar dilusyon yöntemi ile belirlendi. İncelenen E. faecalis suşları, siprofloksasin, eritromisin, tetrasiklin, streptomisin, ampisilin, gentamisin, penisilin ve vankomisine sırasıyla %34.6, %3.8, %3.8, %96.1, %11.5, %92.3, %11.5 ve %3.8 oranında dirençli bulundu. İncelenen 26 suştan 1’inin (%3.8) vankomisine dirençli olduğu saptandı. Bu suşun vankomisin direnç fenotipinin vanA olduğu belirlendi. Bu bulgular, balıklarda streptomisin, gentamisin ve siprofloksasine dirençli suşların yaygın olarak bulunduğunu; düşük oranda da olsa vankomisine dirençli suş bulunması, balıkların VRE kaynağı olarak dikkate alınması gerektiğini gösterdi

Keywords

• Antibiyotik dirençlilik
• balık
• Enterococcus faecalis
• vankomisin

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