The Comparison of the Effects of Oral Antibiotic Ingestion and Intraprostatic Antibiotic Injection in a Rat Model of Chronic Bacterial Prostatitis

Im, Pil Bin; Lee, Dong Hwan; Cho, Yong Hyun

Abstract

PURPOSE
An in vivo study compared the effect of oral antibiotic ingestion to that of intraprostatic antibiotic injection in a rat model of chronic bacterial prostatitis.
MATERIALS AND METHODS
Wistar rats were divided into four experimental groups: oral phosphate buffered saline (PBS) ingestion group (Op group), oral antibiotic ingestion group (Oa group), intraprostatic PBS injection group (Ip group) and intraprostatic antibiotic injection group (Ia group). Escherichia coli Z17 (O2:K1:H ) was inoculated to the prostatic urethra of the 4 experimental groups to develop the chronic bacterial prostatitis rat model. To confirm the chronic bacterial prostatitis, urine bacterial culture, tissue bacterial culture and histopathologic examinations were conducted 4 weeks after inoculation of E. coli. PBS and oral ciprofloxacin were administered orally twice a day for 1 week to the Op and Oa groups, respectively, and were injected into the prostate in the Ip and Ia groups, respectively. Urine bacterial culture, tissue bacterial culture and histopathologic examinations were conducted with specimens obtained 5 weeks after inoculation of E. coli.
RESULTS
Microbiological culture of urine demonstrated that there was no significant difference among any of the four experimental groups (p>0.05). Microbiological culture of the prostate demonstrated that the mean Log10cfu/g of the Ia group was significantly lower than that of the other three experimental groups (p<0.05). The histopathology showed resolving prostatitis in the intraprostatic antibiotic injected groups compared with the other experimental groups.
CONCLUSIONS
This study indicates that the effect of intraprostatic antibiotic injection for chronic bacterial prostatitis was more positive than oral antibiotic ingestion. This result suggests that intraprostatic antibiotic injection would be a treatment modality to overcome the difficulty of passage of antibiotics across blood-prostate barrier into the prostatic tissue.