Open AccessEffect of EDTA on the resistance of clinical isolates of Acinetobacter baumannii to the bactericidal activity of normal human serum
Author(s) -
Antonio Manuel Rodríguez García,
Henry Solar,
Carlos González,
R Zemelman
Publication year - 2000
Publication title -
journal of medical microbiology/journal of medical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.91
H-Index - 117
eISSN - 1473-5644
pISSN - 0022-2615
DOI - 10.1099/0022-1317-49-11-1047
Subject(s) - acinetobacter baumannii , microbiology and biotechnology , virulence , bacteria , ethylene diamine , biology , lipopolysaccharide , antibiotics , pathogen , acinetobacter , drug resistance , chemistry , immunology , pseudomonas aeruginosa , gene , biochemistry , genetics , nuclear chemistry
Acinetobacter baumannii is an opportunist nosocomial pathogen of world-wide importance and produces severe infections in immunocompromised patients. However, the virulence factors contributing to its pathogenic properties are not well known. The effect of normal human serum against 18 clinical isolates of the most prevalent biotypes of A. baumannii in Chile was investigated. The effect of pre-treatment of the cells with ethylene diamine tetraacetic acid (EDTA) or bismuth subsalicylate (BSS), compounds known to decrease the amount of lipopolysaccharide (LPS) and bacterial capsular polysaccharide (CPS), respectively, in other gram-negative bacteria, was evaluated. Most isolates (16 of 18) showed resistance to normal human serum. Prior treatment with EDTA rendered nine of these isolates susceptible to serum, while seven isolates maintained their resistance. Pre-treatment with BSS did not modify the serum-resistant behaviour of the isolates. The results suggest that LPS might be involved in the resistance of A. baumannii to human serum whereas CPS does not seem to contribute to this property.