Ann Lab Med.  2012 Sep;32(5):366-369. 10.3343/alm.2012.32.5.366.

Quinolone-resistant Shigella flexneri Isolated in a Patient Who Travelled to India

• Jeon YL
• Nam YS
• Lim G
• Cho SY
• Kim YT
• Jang JH
• Kim J
• Park M
• Lee HJ

• KMID: 1387353
• DOI: http://doi.org/10.3343/alm.2012.32.5.366

Abstract

We report a recent case in which ciprofloxacin-resistant Shigella flexneri was isolated from a 23-yr-old female patient with a history of travel to India. Prior to her admission to our internal medicine department, she experienced symptoms of high fever and generalized weakness from continuous watery diarrhea that developed midway during the trip. S. flexneri was isolated from the stool culture. Despite initial treatment with ciprofloxacin, the stool cultures continued to show S. flexneri growth. In the susceptibility test for antibiotics of the quinolone family, the isolate showed resistance to ciprofloxacin (minimum inhibitory concentration [MIC], 8 microg/mL), norfloxacin (MIC, 32 microg/mL), ofloxacin (MIC, 8 microg/mL), nalidixic acid (MIC, 256 microg/mL), and intermediate resistance to levofloxacin (MIC, 4 microg/mL). In molecular studies for quinolone resistance related genes, plasmid borne-quinolone resistance genes such as qnrA, qnrB, qnrS, aac(6')-Ib-cr, qepA, and oqxAB were not detected. Two mutations were observed in gyrA (248C-->T, 259G-->A) and 1 mutation in parC (239G-->T). The molecular characteristics of the isolated S. flexneri showed that the isolate was more similar to the strains isolated from the dysentery outbreak in India than those isolated from Korea.

Keyword

Quinolone resistance; Shigella flexneri; Ciprofloxacin resistance

MeSH Terms

Anti-Bacterial Agents/pharmacology
Bacterial Proteins/genetics/metabolism
Drug Resistance, Bacterial/drug effects
Dysentery, Bacillary/microbiology
Feces/microbiology
Female
Humans
India
Mutation
Quinolones/*pharmacology
Shigella flexneri/drug effects/*isolation & purification/metabolism
Travel
Young Adult

Figure

• 

  Fig. 1 Expression of the efflux pump genes in response to ciprofloxacin with reference to the expression levels in the control strain. Expression of tolC, mdfA, and ydhE was measured by real-time PCR in the absence and presence of ciprofloxacin. Each value represents the average of 5 culture replicates, each of which was evaluated twice. Relative gene expression levels were calculated as 2-ΔΔCT, where ΔΔCT=ΔCT (sample) - ΔCT (control) [11]. CIP-: absence of ciprofloxacin; CIP+: presence of ciprofloxacin.

Reference

1. Haukka K, Siitonen A. Emerging resistance to newer antimicrobial agents among Shigella isolated from Finnish foreign travellers. Epidemiol Infect. 2008. 136:476–482.

2. Salam MA, Bennish ML. Antimicrobial therapy for shigellosis. Rev Infect Dis. 1991. 13:Suppl 4. S332–S341.

3. Niyogi SK. Shigellosis. J Microbiol. 2005. 43:133–143.

4. Taneja N. Changing epidemiology of shigellosis and emergence of ciprofloxacin-resistant Shigellae in India. J Clin Microbiol. 2007. 45:678–679.

5. Kuo CY, Su LH, Perera J, Carlos C, Tan BH, Kumarasinghe G, et al. Antimicrobial susceptibility of Shigella isolates in eight Asian countries, 2001-2004. J Microbiol Immunol Infect. 2008. 41:107–111.

6. Kim JY, Kim SH, Jeon SM, Park MS, Rhie HG, Lee BK. Resistance to fluoroquinolones by the combination of target site mutations and enhanced expression of genes for efflux pumps in Shigella flexneri and Shigella sonnei strains isolated in Korea. Clin Microbiol Infect. 2008. 14:760–765.

7. Clinical and Laboratory Standards Institute. Eighteenth Informational supplement, M100-S16. Performance standards for antimicrobial susceptibility testing. 2008. Wanye, PA: Clinical and Laboratory Standards Institute.

8. Morgan-Linnell SK, Becnel Boyd L, Steffen D, Zechiedrich L. Mechanisms accounting for fluoroquinolone resistance in Escherichia coli clinical isolates. Antimicrob Agents Chemother. 2009. 53:235–241.

9. Komp Lindgren P, Karlsson A, Hughes D. Mutation rate and evolution of fluoroquinolone resistance in Escherichia coli isolates from patients with urinary tract infections. Antimicrob Agents Chemother. 2003. 47:3222–3232.

10. Kim HB, Wang M, Park CH, Kim EC, Jacoby GA, Hooper DC. oqxAB encoding a multidrug efflux pump in human clinical isolates of Enterobacteriaceae. Antimicrob Agents Chemother. 2009. 53:3582–3584.

11. Giulietti A, Overbergh L, Valckx D, Decallonne B, Bouillon R, Mathieu C. An overview of real-time quantitative PCR: applications to quantify cytokine gene expression. Methods. 2001. 25:386–401.

12. Drlica K, Zhao X. DNA gyrase, topoisomerase IV, and the 4-quinolones. Microbiol Mol Biol Rev. 1997. 61:377–392.

13. Poole K. Efflux-mediated multiresistance in Gram-negative bacteria. Clin Microbiol Infect. 2004. 10:12–26.

14. Jacoby G, Cattoir V, Hooper D, Martínez-Martínez L, Nordmann P, Pascual A, et al. qnr Gene nomenclature. Antimicrob Agents Chemother. 2008. 52:2297–2299.

15. Pazhani GP, Niyogi SK, Singh AK, Sen B, Taneja N, Kundu M, et al. Molecular characterization of multidrug-resistant Shigella species isolated from epidemic and endemic cases of shigellosis in India. J Med Microbiol. 2008. 57:856–863.