Abstract
Klebsiella pneumoniae is a wide-spread nosocomial pathogen. A rapid and sensitive molecular method for the detection of K. pneumoniae in clinical samples is needed to guide therapeutic treatment. In this study, we first described a loop-mediated isothermal amplification (LAMP) method for the rapid detection of capsular polysaccharide synthesis regulating gene rcsA from K. pneumoniaein clinical samples by using two methods including real-time turbidity monitoring and fluorescence detection to assess the reaction. Then dissemination of K. pneumoniae strains was investigated from ICU patients in three top hospitals in Beijing, China. The results showed that the detection limit of the LAMP method was 0.115 pg/μl DNA within 60 min under isothermal conditions (61°C), a 100-fold increase in sensitivity compared with conventional PCR. All 30 non- K. pneumoniae strains tested were negative for LAMP detection, indicating the high specificity of the LAMP reaction. To evaluate the application of the LAMP assay to clinical diagnosis, of 110 clinical sputum samples collected from ICU patients with clinically suspected multi-resistant infections in China, a total of 32 K. pneumoniae isolates were identified for LAMP-based surveillance of rcsA. All isolates belonged to nine different K. pneumoniae multilocus sequence typing (MLST) groups. Strikingly, of the 32 K. pneumoniae strains, 18 contained the Klebsiella pneumoniae Carbapenemase (KPC)-encoding gene blaKPC-2 and had high resistance to β-lactam antibiotics. Moreover, K. pneumoniae WJ-64 was discovered to contain blaKPC-2 and blaNDM-1genes simultaneously in the isolate. Our data showed the high prevalence of blaKPC-2 among K. pneumoniae and co-occurrence of many resistant genes in the clinical strains signal a rapid and continuing evolution of K. pneumoniae. In conclusion, we have developed a rapid and sensitive visual K. pneumoniae detection LAMP assay, which could be a useful tool for clinical screening, on-site diagnosis and primary quarantine purposes.
Highlights
Materials and MethodsAs a Gram-negative bacterium, Klebsiella pneumoniae has been identified as a major nosocomial pathogen (Fukigai et al, 2007), which can cause pneumonia, bronchitis, urinary tract and wound infections, especially in infants, diabetics, tumor patients, antibiotic users, and elderly people (Podschun and Ullmann, 1998) in the clinical context
In the past two decades, K. pneumoniae has surpassed Escherichia coli as the predominant species isolated from patients with pyogenic liver abscess globally (Liu et al, 2013)
We have established a novel detection assay using the loop-mediated isothermal amplification (LAMP) method, which can be completed within 60 min
Summary
As a Gram-negative bacterium, Klebsiella pneumoniae has been identified as a major nosocomial pathogen (Fukigai et al, 2007), which can cause pneumonia, bronchitis, urinary tract and wound infections, especially in infants, diabetics, tumor patients, antibiotic users, and elderly people (Podschun and Ullmann, 1998) in the clinical context. Antibiotic-resistant Klebsiella pneumoniae emerged in recent years has become a serious problem in clinics (Ali Abdel Rahim and Ali Mohamed, 2014). The rapid and sensitive detection of this pathogen is required if the appropriate therapy is to be administered and outbreaks controlled
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
