Original Article

DETERMINATION OF EXTENDED SPECTRUM BETA-LACTAMASE FREQUENCY OF KLEBSIELLA PNEUMONIAE STRAINS ISOLATED FROM URINARY TRACT INFECTIONS AND TYPING WITH ISOELECTRIC FOCUSING METHOD

  • Mine HOSGÖR LIMONCU
  • Safak ERMERTCAN
  • Cengiz ÇAVUSOGLU
  • Bayri ERAÇ

Received Date: 06.02.2007 Accepted Date: 17.04.2007 Turk J Pharm Sci 2007;4(3):151-158

Abstract Extended spectrum beta-lactamase (ESBL) presence was investigated in Klebsiella pneumoniae strains which were the ethiological agents of urinary tract infections and typed with isoelectric focusing (IEF) method. The antibiotic sensitivities of 52 K. pneumoniae strains were determined by disc diffusion method and ESBL were found in 12 strains (23 %) by double disc synergy test. Minimum inhibitory concentration (MIC) values of ESBL (+) K. pneumoniae strains for ceftazidime (CAZ) and cefotaxime (CTX) were investigated by E-test and isoelectric points of ESBL enzymes were determined by polyacrilamide gel electrophoresis. When the strains’ sensitivity patterns were investigated for 3rd generation cephalosporins and aztreonam, 6 strains had ESBL premise sign with at least one antibiotic. Band pattern which focused around pl 7.6 was determined in 11 of 12 strains by IEF method. MIC values were found 16 μg/mL and over for CAZ and 12 μg/mL and over for CTX in 5 of these strains. When pI’s and antibiotic susceptibility patterns were analysed, 5 of 12 isolates had a band and susceptibility patterns suggesting SHV-2. Özet Bu çalismada, idrar yolu infeksiyonlarindan izole edilen Klebsiella pneumoniae kökenlerinde genislemis spektrumlu beta-laktamaz (GSBL) varligi arastirildi ve tiplendirmeleri izoelektrik odaklama yöntemi ile yapildi. Elli iki K. pneumoniae kökeninin antibiyotik duyarliliklari disk difüzyon yöntemi ile belirlendi. On iki (% 23) kökende çift disk sinerji yöntemi ile GSBL varligi saptandi. Bu kökenlerin seftazidim (CAZ) ve sefotaksim (CTX) minimum inhibitör konsantrasyon (MIK) degerleri E-test yöntemi kullanilarak, GSBL enzimlerinin izoelektrik noktalari ise poliakrilamid jel elektroforezi yöntemi ile belirlendi. Kökenlerin üçüncü jenerasyon sefalosporinler ve aztreonam duyarlilik paternleri dikkate alindiginda, alti kökende en az bir antibiyotik ile GSBL öncü belirtisi saptandi. Izoelektrik odaklama yöntemi ile 12 kökenin 11’inde pI 7.6 olan bantlar gözlendi. Bu kökenlerin besinde CAZ MIK’i 16 μg/mL ve üzerinde, CTX MIK’i 12 μg/mL ve üzerinde bulundu. Sonuç olarak, antibiyotik duyarlilik paternleri ve izoelektrik noktalari gözönüne alindiginda bu bes kökende bulunan enzimlerin SHV-2 olabilecegi düsünüldü.

Keywords: Beta-lactamase, Klebsiella pneumoniae, isoelectric focusing