Screening of Rectal Swabs for Carbapenem Non-susceptible Bacteroides fragilis Group Bacteria in Hospitalized Children

Öz

Objective: The aim of this study was to investigate the carbapenem resistance profiles and risk factors for colonization with carbapenem-resistant Bacteroides group CR-B in pediatric patients hospitalized in a tertiary university hospital in Turkey.Material and Methods: A prospective case-control study was performed. Rectal swab specimens n=1361 were collected from 680 hospitalized pediatric patients. All anaerobic colonies isolated from selective medium were identified using MALDI-TOF Vitek MS, bioMérieux automated system and antibiotic susceptibility testing for meropenem by e-test. The presence of the cfiA gene was investigated by PCR method.Results: A total of 1361 rectal swab specimens were collected from all 680 hospitalized children. During the screening period 80 Bacteroides fragilis group BFG microorganisms with a MIC>0.125 mg/L 12% were isolated from rectal swab specimens of 680 patients. Seven different BFG species were recovered, the main species were B.fragilis n=29; 36% , B.ovatus n=16; 20% , B.vulgatus n=13; 16% , P.distasonis n=12; 15% , B.theoiotomicron n=5; 6% , B.uniformis n=4; 5% and B.caccae n=1; 1% . The presence of cfiA gene was detected in 25 31% isolates, while 29 36% isolates were not susceptible to meropenem MIC>2 mg/L . Conclusion: The high carriage rate in our hospitalized children for carbapenem-non-susceptible Bacteroides fragilis group creates a great risk for serious infections and mortality and deserves significant attention

Anahtar Kelimeler

• Bacteroides fragilis group,carbapenem nonsusceptible,children

Hastanede Yatan Çocukların Rektal Sürüntülerinde Karbapenem Duyarlı Olmayan Bacteroides fragilis Grup Bakteri Taraması

Öz

Amaç: Bu çalışmanın amacı, Türkiye’de üçüncü düzey bir üniversite hastanesinde yatmakta olan çocuk hastalarda karbapenem dirençli Bacteroides grup KD-B bakteriler ile kolonizasyon için risk faktörlerini ve karbapenem direnç profilini araştırmaktı.Gereç ve Yöntem: Prospektif vaka-kontrol çalışması uygulandı. Hastanede yatmakta olan 680 çocuk hastadan 1361 rektal swab toplandı. Selektif mediumdan izole edilen tüm anaerobik kolonilere identifikasyon için MALDI-TOF Vitek MS, bioMérieux otomatize sistem ve meropenem duyarlılığı için e-test uygulandı. cfiA geni PCR yöntemiyle araştırıldı.Bulgular: Hastanede yatmakta olan 680 çocuk hastadan 1361 rektal swab toplandı. Tarama süresince MIC>0.125 mg/L olan 80 Bacteroides fragilis group BFG bakteri izole edildi. Yedi farklı tür BFG saptandı, sıklık sırasına göre şöyleydi: B.fragilis n=29; %36 , B.ovatus n=16; %20 , B.vulgatus n=13; %16 , P.distasonis n=12; %15 , B.theoiotomicron n=5; %6 , B.uniformis n=4; %5 ve B.caccae n=1; %1 . 25 izolatda %31 cfiA geni saptanırken, meropeneme hassas olmama MIC>2 mg/L 29 izolatda %36 belirlendi.Sonuç: Çalışmamızda, hastanede yatan çocuklarda karbapenem hassas olmayan Bacteroides fragilis grup bakteriler ile kolonizasyon oranları yüksek bulunmuştur ki, bu durum ciddi enfeksiyonların oluşması, artmış mortalite açısından önemlidir ve dikkate alınmalıdır

Anahtar Kelimeler

• Bacteroides fragilis grup,karbapenem hassas olmama,çocuklar

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