Studies on in Vitro Antibacterial Activity of a New Cephalosporin Derivative Antibiotic, Cefoperazone, Stability of Solution and Local Application Against Purulent Otitis Media

Abstract

Antibacterial activity, stability of solution and clinical evaluation of a new cephalosporin derivative antibiotic, cefoperazone (CPZ), were performed with the results which might lead to the following conclusions:
1) In vitro antibacterial activity: The minimum inhibitory concentration of CPZ was tested by an agar plate dilution method. CPZ results an excellent, broad spectrum antibacterial activity against standard strains of various bacteria. CPZ had same antibacterial spectrum like those of other cephalosporin antibiotics. The MIC of Staphylococcus aureus isolated from otorrhoea was distributed at a range from ≤0.2 to 50μg/ml of CPZ, showing its peak at 1.56μg/ml. Other strains of Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae were inhibited by ≤0.2 to 12.5μg/ml of CPZ. CPZ showed the MICs of 0.78 to 12.5μg/ml, its peak at 6.25/g/ml against 60 strains of pathogenic Pseudomonas aeruginosa.
2) Stability of CPZ solution: As to the stability of 20mg/ml of CPZ there was no change in its colour and pH however, antibacterial activity decreased when the solution was kept at 5°C or 37°C for 14 days.
3) Results of clinical treatment: When administration of CPZ was applied locally in 31 cases of acute and chronic purulent otitis media, results were good in 21 cases, fair in 6 cases and poor in 4 cases. When good and fair effects were considered together, the rate of effectiveness was 27 cases 87.1 per cent.
No side effect was observed when CPZ solution was locally applied.