Clinical and Microbiological Feature of Quinolone-Resistant Klebsiella pneumoniae Pneumonia in a University Hospital

Song, Joon Young; Lee, Kyung Mi; Lee, Yeon Joo; Eom, Joong Shik; Sohn, Jang Wook; Cheong, Hee Jin; Kim, Woo Joo; Kim, Min Ja; Park, Seung Chull

Abstract

BACKGROUND: Klebsiella pneumoniae is an opportunistic pathogen which causes a spectrum of extra- intestinal infections. Since early 1980s, many outbreaks of extended-spectrum beta-lactamase (ESBL) producing K. pneumoniae have been reported. Using quinolone as an alternative therapeutic antibiotics also induced increased resistance to quinolones. Therefore, we evaluatedted the clinical and microbiological features of pneumonia caused by quinolone-resistant K. pneumoniae (QRKP).
METHODS
From March of 1998 to April of 2000, 345 cases of K. pneumoniae pneumonia had been admitted to Korea University Guro Hospital. We retrospectively reviewed medical records of 75 cases. Thirty patients with pneumonia due to QRKP (case patients) were compared to 45 patients with pneumonia due to quinolone-susceptible K. pneumoniae (QSKP: control patients). We also performed antimicrobial susceptibility test (disc diffusion method and agar dilution method) and RAPD (random amplified polymorphic DNA) analysis to differentiate the isolates in resistant strains.
RESULTS
Of 345 episodes of pneumonia, 30 (8.7 %) were caused by QRKP. Multivariate analysis re-vealed that prior antibiotics use was an independent risk factor for QRKP pneumonia. Among prior antibiotics, quinolone and the third generation cephalosporin were independently related to quinolone resistance. Although mortality rate was not high, QRKP pneumonia was associated with a significantly longer treatment duration and poor treatment response (P=0.009 and 0.007 respectively). According to the antimicrobial susceptibility test, quinolone resistance was significantly associated with the multi-drug resistance. RAPD analysis showed that 28 quinolone resistant strains belonged to only 4 genotypes, suggesting that patient- to-patient transmission of a few strains within the hospital occurred.
CONCLUSION
QRKP pneumonia had a significant impact on clinical outcome and quinolone resistance was associated with multiple resistance to other antibiotics. It should be emphasized that judicious use of antibiotics as well as barrier precautions is required to reduce future outbreak and spread of QRKP.