Enterotoxigenicity of Klebsiella pneumoniae associated with childhood gastroenteritis in Madras, India.

Klebsiella pneumoniae was isolated as the predominant growth from 12 of 100 children under 3 years of age suffering from acute diarrhea. Of the 12 isolates, SA1, SA2, SA4, SA5, SA6 produced a secretogenic response in the ligated rabbit ileal loop, and one isolate, SA3, induced a diarrheagenic response in suckling mice. Two isolates, SA7 and SA8, were diarrheagenic in both assays. Strains SA9, SA10, SA11, and SA12 were found to be non-enterotoxigenic. These isolates belonged to serotypes K6, 16, 25, 30, 39, 46, 49, 53, 66, and 81. All eight enterotoxigenic strains were resistant to ampicillin, streptomycin, ceftazidime, cefuroxime, and cotrimoxazole. Only quinolones such as ciprofloxacin and norfloxacin appear to be effective against enterotoxigenic K. pneumoniae.