Knowledge Repository
-
BROWSE
-
ICDDR,B PUBLICATIONS
-
CONNECT
Increasing spectrum in antimicrobial Resistance of shigella isolates in Bangladesh: resistance to azithromycin and ceftriaxone and decreased susceptibility to ciprofloxacin
Download
Adobe PDF
(205.17 kB)
Published
2007-09-09T02:00:59Z
Author(s)
Mahbubur Rahman, Mahbubur
Shoma, Shereen
Rashid, Harunur
Arifeen, Shams El
Baqui, A.H.
Siddique, A.K.
Nair, G.B.
Sack, David A.
Metadata
Antimicrobial resistance of Shigella isolates in Bangladesh, during 2001-2002, was studied and compared with that of 1991-1992 to identify the changes in resistance patterns and trends. A significant increase in resistance to trimethoprim-sulphamethoxazole (from 52% to 72%, p<0.01) and nalidixic acid (from 19% to 51%, p<0.01) was detected. High, but unchanged, resistance to tetracycline, ampicillin, and chloramphenicol, low resistance to mecillinam (resistance 3%, intermediate 3%), and to emergence of resistance to azithromycin (resistance 16%, intermediate 62%) and ceftriaxone/cefixime (2%) were detected in 2001-2002. Of 266 recent isolates, 63% were resistant to ≥3 anti-Shigella drugs (multidrug-resistant [MDR]) compared to 52% of 369 strains (p<0.007) in 1991-1992. Of 154 isolates tested by E-test in 2001-2002, 71% were nalidixic acid-resistant (minimum inhibitory concentration [MIC] ≥32 µg/mL) and had 10-fold higher MIC 90
(0.25 µg/mL) to ciprofloxacin than that of nalidixic acid-susceptible strains exhibiting decreased ciprofloxacin susceptibility, which were detected as ciprofloxacin-susceptible and nalidixic acid-resistant by the disc-diffusion method. These strains were frequently associated with MDR traits. High modal MICs were observed to azithromycin (MIC 6 µg/mL) and nalidixic acid (MIC 128 µg/mL) and low to ceftriaxone (MIC 0.023 µg/mL). Conjugative R-plasmids-encoded extended-spectrum ß-lactamase was responsible for resistance to ceftriaxone/cefixime. The growing antimicrobial resistance of Shigella is worrying and mandates monitoring of resistance. Pivmecillinam or ciprofloxacin might be considered for treating shigellosis with caution.