Open AccessNalidixic acid resistance predicting reduced ciprofloxacin susceptibility of Salmonella enterica serovar Typhi
Author(s) -
Shyamapada Mandal,
Manisha DebMandal,
Nishith Kumar Pal
Publication year - 2012
Publication title -
asian pacific journal of tropical disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.208
H-Index - 33
ISSN - 2222-1808
DOI - 10.1016/s2222-1808(12)60226-6
Subject(s) - nalidixic acid , ciprofloxacin , minimum inhibitory concentration , salmonella typhi , microbiology and biotechnology , salmonella enterica , serotype , salmonella , biology , bacteria , antibiotics , escherichia coli , biochemistry , genetics , gene
Objective: To evaluate the applicability of nalidixic acid (Nx) resistance in determining reduced\udsusceptibility to ciprofloxacin (Cp) among Salmonella enterica serovar Typhi (S. Typhi) clinical\udisolates. Methods: The correlation between Cp MIC (minimum inhibitory concentration) values\udand that Nx, and between Cp MICs and zone diameter of inhibition (ZDI) around 30-毺 g Nx\uddisc for 421 S. Typhi isolates were determined by scattergram analysis. The specificity and\udsensitivity, in determining Cp reduced-susceptibility, of Nx resistance by disk testing and MIC\uddetermination were calculated. Results: For the test S. Typhi isolates the simultaneous presence\udof Nx-resistance and decreased Cp susceptibility has been recorded. The Nx sensitive S. Typhi\udisolates were sensitive to Cp; the disc diffusion and MIC breakpoints cannot determine Cp\udresistance. The sensitivity of Nx disc was 100 %, and the specificity was 89.20 % in determining\udCp reduced-susceptibility of S. Typhi isolates; when MICs of Nx were compared with MICs of Cp,\udthe sensitivity and specificity of the approach were 100 % and 95.95 %, respectively. Conclusion:\udAssociation between Nx-resistance and reduced susceptibility to Cp was noticed (P 曑 0.001)\udamong the S. Typhi isolates, and thus Nx-resistance might be an indication of decreased\udsusceptibility to Cp