Comparative In Vitro Susceptibility of Proteus Species Isolated from Clinical Specimens to Honey, Ciprofloxacin and Tetracycline

Comparative in vitro susceptibility of Proteus species isolated from clinical specimens to ciprofloxacin, tetracycline and honey was evaluated using standard microbiological techniques. Honey was diluted by percent volume per volume concentration of 100%(neat), 80%(v/v), 60%(v/v), 40% (v/v), 20% (v/v) and 10% (v/v) and its antimicrobial activity against Proteus species compared to ciprofloxacin and tetracycline. A honey concentration of 100% (neat) had the highest effect on Proteus species with a mean zone of inhibition of 28mm. Concentrations of 80%(v/v), 60%(v/v), 40% (v/v), and 20% yielded mean inhibition zones of 26mm, 23mm, 20mm, and 15mm respectively. Only four isolates gave inhibition zones at 20%(v/v) dilution. Tetracycline and ciprofloxacin inhibited Proteus species with comparatively lower mean zones of inhibition (15mm for tetracycline and 16mm for ciprofloxacin). The minimum inhibitory concentration (MIC) of honey for 86.7% of the isolates was 40%(v/v) and for the remaining was 20%(v/v). The MBC values were the same for their MIC. This study reveals a significant level of susceptibility of Proteus species isolated from clinical specimens to honey, tetracycline and ciprofloxacin, with undiluted honey exhibiting comparatively higher zones of inhibition. It also revealed a high level of resistance to tetracycline by Proteus species isolated from automobile wounds. Further studies using uniform concentrations of the honey and the evaluated antibiotics may be necessary before honey may be considered a better treatment option.