A comparative study of in vivo efficacy of currently used antibiotics in murine model of klebsiella pneumonia

A comparative in-vivo efficacy of commonly used antibiotics was evaluated in the murine model of Klebsiella pneumonia. Six groups of immunosuppressed (cyclophosphamide 80mg/kg i.p. on -4 and -1 day) female Wistar rats (n=6-12) were employed to induce pneumonia. Bacterial inoculum of strength 1x 10⁷ CFU/ml of Klebsiella pneumoniae strain isolated from sputum in the Department of Microbiology, Kasturba Medical College, Mangalore was injected intratracheally. Gentamicin (0.032g/kg body weight/day), Levofloxacin (0.036g/kg body weight/12hrly), Cefepime (0.18 g/kg body weight/12hrly), Aztreonam (0.18g/kg body weight/8hrly) and Meropenem (0.09 mg/kg body weight/8hrly) were administered i.p. within 4 hours following bacterial inoculation and continued for 5 days. On the sixth day, rats were sacrificed and the pneumonic lung tissues were used for bacterial count and histopathological studies. Levofloxacin significantly offered protection in Klebsiella pneumonia. Aztreonam seems to be a better choice to Cefepime and Gentamicin. Cefepime is found to be an effective antibiotic whereas Gentamicin is not effective against the local strains of K.pneumoniae. Thus in-vivo efficacy of antibiotic data may help to substantiate the choice of antibiotic against local strains of pneumopathogens. Also, these results may ensure more scientific authenticity than in-vitro bacteriological investigation reports.