Rahman, MahbuburShoma, ShereenRashid, HarunurEl Arifeen, ShamsBaqui, A HSiddique, A KNair, G BSack, D A2007-06-082009-05-272007-06-082009-05-272007-06-08Rahman M, Shoma S, Rashid H, El Arifeen S, Baqui AH, Siddique AK, Nair GB, Sack DA. Increasing spectrum in antimicrobial resistance of Shigella isolates in Bangladesh: resistance to azithromycin and ceftriaxone and decreased susceptibility to ciprofloxacin. Journal of Health, Population, and Nutrition. 2007 Jun; 25(2): 158-67http://imsear.searo.who.int/handle/123456789/547Journal of Health, Population, and Nutrition.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 > or =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] > or =32 microg/mL) and had 10-fold higher MIC90 (0.25 microg/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 microg/mL) and nalidixic acid (MIC 128 micdrog/mL) and low to ceftriaxone (MIC 0.023 microg/mL). Conjugative R-plasmids-encoded extended-spectrum beta-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.engAnti-Bacterial Agents --pharmacologyAzithromycin --pharmacologyBangladeshCeftriaxone --pharmacologyCiprofloxacin --pharmacologyColony Count, MicrobialDose-Response Relationship, DrugDrug Resistance, BacterialDrug Resistance, Multiple, BacterialDysentery, Bacillary --drug therapyHumansMicrobial Sensitivity TestsSentinel SurveillanceShigella --drug effectsSpecies SpecificityTreatment OutcomeJournal Article