Citation Information :
Kumar V, Sen MR, Nigam C, Gahlot R, Kumari S. Burden of different beta-lactamase classes among clinical isolates of AmpC-producing Pseudomonas aeruginosa in burn patients: A prospective study. Indian J Crit Care Med 2012; 16 (3):136-140.
Background: Pseudomonas aeruginosa is one of the most common pathogens causing infections in burns, and shows increasing resistance to β-lactam antibiotics by producing different classes of beta-lactamases. It is also not unusual to find a single isolate that expresses multiple β-lactamase enzymes, further complicating the treatment options. Thus, in this study, we aimed to determine the coexistence of different beta-lactamase enzymes in clinical isolates of P. aeruginosa in the burn ward. Materials and Methods: A total of 101 clinical isolates of P. aeruginosa from the burn ward were identified and tested for the presence of different beta-lactamase enzymes (extended spectrum beta lactamase (ESBL), Amp C and metallo β-lactamases (MBL) from October 2006 to May 2009. In vitro susceptibility pattern of antipseudomonal antibiotics was done by the Kirby Bauer disc diffusion method. Results: A total of 33 (32.7%) isolates were confirmed to be positive for AmpC beta-lactamase. Co-production of AmpC along with ESBL and MBL was reported in 24.5% and 45.5% isolates, respectively. A total of 12 (11.9%) isolates were resistant to three or more antibiotic classes (multidrug resistance). Imipenem and piperacillin/tazobactum showed high sensitivity, with 86.1% and 82.2%, respectively. Conclusion: This study reveals the high prevalence of multidrug- resistant P. aeruginosa producing beta-lactamase enzymes of different mechanisms in this region from burn patients. The emerging antimicrobial resistance in burn wound pathogens poses serious therapeutic challenge. Thus proper antibiotic policy and measures to restrict the indiscriminate use of cephalosporins and carbapenems should be taken to minimize the emergence of this multiple beta -lactamase producing pathogen.
The impact of nosocomially-acquired resistant Pseudomonas aeruginosa infection in a burn unit. J Trauma 2007;63:164-71.
Resistance mechanisms in Pseudomonas aeruginosa and other non fermentative gram-negative bacteria. Clin Infect Dis 1998;27:S93-9.
Pseudomonas aeruginosa: Resistance and therapeutic options at the turn of the new millennium. Clin Microbiol Infect 2007;13:560-78.
Occurrence and detection of AmpC beta-lactamases among Gram negative clinical isolates using a modified three-dimensional test at Guru Tegh Bahadur Hospital, Delhi, India. J Antimicrob Chemother 2008;51:415-8.
An update on newer beta-lactamases. Indian J Med Res 2007;126:417-8.
Performance standards for antimicrobial susceptibility testing: Sixteenth informational supplement. Wayne, PA: CLSI; 2006. p. M100-S16.
In vitro antagonism of β-lactam antibiotics by Cefoxitin. J Antimicrob Chemother 1982; 21:968-75.
Wayne PA: CLSI; 2005. p. M100-S15.
Imipenem-EDTA disk method for differentiation of metallo β lactamase-producing clinical isolates of Pseudomonas spp. and Acinetobacter spp. J Clin Microbiol 2002;40:3798-801.
Susceptibility patterns and cross-resistance of antibiotics against Pseudomonas aeruginosa isolated from burn patients in the South of Iran. Burns 2006;32:343-7.
Antimicrobial susceptibility profile of Pseudomonas aeruginosa isolates in Egypt. J Urol 2008;-180:176-81.
Multiple mechanisms of antimicrobial resistance in Pseudomonas aeruginosa, our worst nightmare? Clin Infect Dis 2002;34:634-40.
Detection of extended spectrum beta lactamase in Pseudomonas aeruginosa. Indian J Pathol Microbiol 2008; 51:222-4.
Prevalence of metallo beta lactamase producing Pseudomonas aeruginosa in hospitalized patients. Indian J Med Res 2005;122:148-52.
Antimicrobial susceptibility and ESBL prevalence in P.aeruginosa isolated from burn patients in North West of Pakistan. Burns 2009;35:1020-5.
AmpC β -lactamase producing bacterial isolates from Kolkata hospital. Indian J Med Res 2005;122:224-33.
Inducible AmpC Beta-Lactamase producing Pseudomonas aeruginosa isolated in a rural hospital of central India. Journal of Clinical and Diagnostic Research 2009;3:1921-7.
Phenotypic detection of extended spectrum and AmpC β -lactamases by a new spot inoculation method and modified three dimensional extract test: Comparison with the three dimensional extract tests. J Antimicrob Chemother 2004;54:684-7.
Presence of different beta-lactamase classes among clinical isolates of Pseudomonas aeruginosa expressing AmpC beta-lactamase enzyme. J Infect Dev Ctries 2010;4:239-42.
Carbapenemase: A problem in waiting? Curr Opin Microbiol 2000;3:489-95.
Prevalence of metallo beta lactamase (MBL) producing Pseudomonas spp. and Acinetobacter spp. in a tertiary care hospital in India. J Infect 2006;52:311-4.
Incidence of metallo beta lactamase producing Pseudomonas aeruginosa in ICU patients. Indian J Med Res 2008;127:398-402.