Publication: Gram negatif çomaklarda genişlemiş spektrumlu ve kromozomal indüklenebilir beta-laktamaz varlığının saptanmasında farklı yöntemlerin etkinliğinin karşılaştırılması
Abstract
Hastaneden soyutlanan gram negatif bakterilerde genişlemiş spektrumlu beta-laktamaz (GSBL) ve indüklenebilir beta-laktamaz (İBL) üretimine bağlı antibiyotik direnç oranlarının belirlenmesi hem tedavi başarısı hem de antibiyotik direnç durumunun bilinmesi açısından önemlidir. Bu amaçla çalışmamızda çeşitli klinik örneklerden soyutlanan 143 gram negatif bakteride GSBL varlığı Çift Disk Sinerji Yöntemi (ÇDSY), Üç Boyutlu Yöntem (ÜBY), Tarama ve Fenotipik Doğrulama Yöntemleri (Disk Difüzyon ve Minimal İnhibitör Konsantrasyon: MİK) ile karşılaştırılarak; İBL varlığı ise disk yakınlaştırma yöntemi (DYY) ile araştırılmıştır. Çalışmamızda GSBL saptanmasında indükleyici antibiyotik olarak amoksisilin-klavulonik asit, İBL saptanmasında ise imipenem, her iki yöntemde hedef antibiyotik olarak da sefotaksim, sefepim, seftazidim, sefoperazon ve aztreonam kullanılmıştır. Gram negatif çomakların 102'sinde (%71.3) GSBL varlığı saptanmıştır. Toplam 102 GSBL pozitif suşun arasında 82'si (%80.4) MİK yöntemi, 60'ı (%58.8) disk difüzyon yöntemi, 37'si (%36.3) ÇDSY, 12'si (%11.8) ÜBY, 10'u (%9.8) tarama yöntemi ile saptanmıştır.DYY ile suşların 21'inde (%14.7) İBL, 19'unda (%13.3) ise stabil dereprese mutantlar saptanmıştır. Sonuç olarak; en yüksek GSBL pozitifliği Fenotipik Doğrulama Yöntemlerinden biri olan MİK yöntemi ile saptanmıştır (p<0.001).
Comparison of Efficiency of Different Methods in Determination of Extended Spectrum and Chromosomal Inducible Beta-lactamase Presence in Gram Negative Rods Determination of antibiotic resistance rates depending upon production of extended-spectrum beta-lactamase (ESBL) and inducible beta-lactamase (IBL) in gram negative rods derived from hospitals, is important both for therapy success and awareness of antibiotic resistance state. In this purpose, in 143 gram negative rods derived from various clinical samples, ESBL presence was compared with Double Disk Synergy Method (DDSM), Three Dimensional Method (TDM), Screening and Phenotypic Confirmatory Methods (Disk Diffusion and Minimal Inhibitory Concentration:MIC); and IBL presence was compared with Disk Approximation Method (DAM). In our study, amoxicillin-clavulonic acid was used as inducer antibiotic for ESBL detection and imipenem was used for IBL detection. Cefotaxime, cefepime, ceftazidime,cefoperazone and aztreonam were used as target antibiotics in both methods. Among 102 (71.3%) gram negative rods, ESBL presence was detected. Among the whole 102 ESBL species, 82 was detected (80.4%) with MIC, 60 (58.8%) with disk diffusion method, 37 (36.3%) with DDSM, 12 (11.8%) with TDM, 10 (9.8%) with Initial Screen Method. With DAM, IBL in 21 (14.7%) and stabil derepressant mutants in 19 (13.3%) was detected. In conclusion, the highest ESBL positivity was obtained with MIC determination which is one of the Phenotypic Confirmatory Methods (p<0.001).
Comparison of Efficiency of Different Methods in Determination of Extended Spectrum and Chromosomal Inducible Beta-lactamase Presence in Gram Negative Rods Determination of antibiotic resistance rates depending upon production of extended-spectrum beta-lactamase (ESBL) and inducible beta-lactamase (IBL) in gram negative rods derived from hospitals, is important both for therapy success and awareness of antibiotic resistance state. In this purpose, in 143 gram negative rods derived from various clinical samples, ESBL presence was compared with Double Disk Synergy Method (DDSM), Three Dimensional Method (TDM), Screening and Phenotypic Confirmatory Methods (Disk Diffusion and Minimal Inhibitory Concentration:MIC); and IBL presence was compared with Disk Approximation Method (DAM). In our study, amoxicillin-clavulonic acid was used as inducer antibiotic for ESBL detection and imipenem was used for IBL detection. Cefotaxime, cefepime, ceftazidime,cefoperazone and aztreonam were used as target antibiotics in both methods. Among 102 (71.3%) gram negative rods, ESBL presence was detected. Among the whole 102 ESBL species, 82 was detected (80.4%) with MIC, 60 (58.8%) with disk diffusion method, 37 (36.3%) with DDSM, 12 (11.8%) with TDM, 10 (9.8%) with Initial Screen Method. With DAM, IBL in 21 (14.7%) and stabil derepressant mutants in 19 (13.3%) was detected. In conclusion, the highest ESBL positivity was obtained with MIC determination which is one of the Phenotypic Confirmatory Methods (p<0.001).