Shigella and the fluorinated quinolones.

Between July 1996 to June 1997 a total of 531 Stool samples from cases of acute diarrhoea, dysentry, colitis admitted to Kasturba Medical College Hospital, Manipal were investigated. Shigella were isolated from 29 samples (5.46%). Out of them, Shigella flexneri were 16 (55.17%), Shigella boydii 8 (27.58%), Shigella dysentriae 3 (10.34%) and Shigella sonnei 2 (6.89%). Five strains of Shigella flexneri and one strain of Shigella dysentriae were found to show resistance to Nalidixic acid and the newer fluoroquinolones viz., Ciprofloxacin, Norfloxacin and Ofloxacin. The in vitro 'R' factor transfer study showed that the resistance was not transferable.