The effect of intraurethral hyaluronic acid on healing and fibrosis in rats with experimentally induced urethral trauma

Purpose To assess the efficacy of hyaluronic acid (HA) application after urethral trauma for preventing spongiofibrosis and inflammation in the early period. Methods A total of twenty-four rats were divided into 3 groups, with 8 rats in each. The urethra was traumatized with a 24 G needle sheath in all rats. Group 1 of rats were applied 0.9% saline solution twice a day, Group 2 were applied 0.9% saline solution and sodium HA 1% once a day, Group 3 were applied 1.0% HA twice a day. After 21 days, penectomy was performed in all rats. Inflammation, spongiofibrosis, hyperemia and edema in the urethra were investigated for each group. Results Histopathologic analysis revealed less fibrosis in both group 2 and group 3 compared to Group 1 ( p = 0.004). There were no statistically significant differences among the groups in terms of inflammation, hyperemia, edema and congestion ( p = 0.563, p = 0.069, p = 0.069, p = 0.068, respectively). Severe fibrosis was observed in 6 (75%) rats in Group 1, and in none of the rats of Group 2 or Group 3. With respect to spongiofibrosis compared to the control group, both Group 2 and Group 3 have statistically significant differences ( p = 0.004). Moderate spongiofibrosis was observed in 5 (62.5%) rats in Group 2 and in 3 (37.5%) rats in Group 3. Statistically, there were no significant differences in respect of severity between Group 2 and Group 3 ( p = 0.014). Conclusion Intraurethral HA application after urethral trauma can decrease spongiofibrosis.