ABSTRACT
PURPOSE: Sporadic excellent treatment results of intra-prostatic antibiotic injections against resistant chronic prostatitis were reported without sufficient background. So, for the scientific base of this effective treatment modality, we studied the tissue distribution and concentration of the ofloxacin after intraprostatic injection of formula which is designed for sustained release ofloxacin at least for four weeks. MATERIAL AND METHODS: 28 male dogs aged over 2 and ofloxacin designed to release over four weeks were used. The ofloxacin 12mg and poly(D,L-lactic) acid 28mg were prepared for sustained releasing formula and resolved in 1ml of 1.5% sodium carboxymethyl cellulose solution. Dogs were grouped into two, 8 control and 16 experiments for open injection. For control, oral ofloxacin 100mg was given twice a day for two and four weeks and for experimental groups, the new formula were injected at right lobe of prostate directly. The ofloxacin concentration was measured by high performance liquid chromatography(HPLC). RESULTS: Oral ofloxacin 2,800(2 weeks) and 5,600(4 weeks) were given for control and tissue concentration of ofloxacin were relatively even at all partitions of the prostate, 7.4+/-1.4(2 weeks) and 9.2+/-1.3mg/ml(4 weeks) and the blood level were 3.6-5.1mg/ml. In experimental groups, the only 12mg of ofloxacin was given and tissue concentration were 10.5+/-3.0(1 weeks), 13.8+/-4.5(2 weeks), 7.1+/-0.9(3 weeks) and 7.7+/-3.0mg/ml(4 weeks) in rights and 8.0+/-1.1(1 weeks), 10.2+/-4.2(2 weeks), 5.1+/-1.4(3 weeks) and 7.6+/-0.8(4 weeks)mg/ml in left lobes suggesting communication of blood between two lobes, and blood concentration were 0.16-0.59mg/ml. In histologic examination, the formula were localized between stroma and their size were reduced with time. CONCLUSIONS: Authors conclude that there are free communication of blood between two lobes of prostate and one direct injection of this sustained releasing formula ofloxacin into prostate can be a substitute with local effects without disturbing prostatic tissue level which reducing number or medication in future.