Effect Of Low-dose Erythromycin On The Proliferation Of Granulation Tissue After Tracheal Injury

Objective To investigate the effect of low-dose erythromycin on the proliferation of granulation tissue after tracheal injury and the possibility of preventing and treating tracheal stenosis.Methods Fourty-two rabbits were randomly divided into 7 groups(n=6each),group NS(saline control group),group PG(penicillin group),group EM(low-dose erythromycin group),group EM+PG(low-dose erythromycin and penicillin group),group BS(budesonide group),group EM+BS(low-dose erythromycin and budesonide group),group EM+PG+BS(low-dose erythromycin,penicillin and budesonide group).All rabbits received tracheotomy,and the tracheal mucosa was scraped 20 times with a nylon brush for tracheal stenosis model.Rabbits were treated with corresponding drugs from a week before operation to 9 days after operation.The concentrations of transforming growth factor-beta 1(TGF-?1),vascular endothelial growth factor(VEGF),interleukin(IL)-6,IL-8 in sera and bronchoalveolar lavage fluid(BALF)were determined and the tracheal specimens were collected for measuring degree of stenosis on the 10 th day after operation.Results The sera and BALF concentrations of TGF-?1,VEGF,IL-6 and IL-8 in group EM,EM+PG,EM+BS and EM+PG+BS,which were treated with low-dose erythromycin,were significantly lower than that in group NS,PG and BS which were treated without erythromycin(all P<0.05).Compared with the other groups,the sera and BALF concentrations in group EM+PG+BS was the lowest(all P<0.05).There was no statistical significance in multiple comparison between group NS,PG and BS(all P>0.05).And there was no statistical significance in multiple comparison between group EM,EM+PG,EM+BS(all P>0.05).All 42 rabbits had tracheal stenosis by different degrees of proliferation of granulation tissue.The degree of tracheal stenosis in Group EM,PG,EM,EM+PG,BS,EM+BS and EM+PG+BS were(53.3±4.4)%,(48.2±5.0)%,(24.3±4.4)%,(29.5±3.2)%,(47.8±6.5)%,(27.9±3.1)%,(15.6±2.0)%,respectively.The degree of tracheal stenosis in group EM,EM+PG,EM+BS and EM+PG+BS was significantly lower than that in group NS,PG and BS,which had statistical differences(all P<0.05).Compared with the other groups,the degree of tracheal stenosis in group EM+PG+BS was the lowest(all P<0.05).Conclusions Low-dose erythromycin can effectively inhibit the proliferation of granulation tissue after tracheal injury in rabbits.It can reduce the degree of tracheal stenosis after tracheal injury and the restenosis rate after the treatment of benign tracheal stenosis.And it shows better effectiveness,especially combined with other antibiotics and glucocorticoid.It might have potential clinical value in the prevention and treatment of benign tracheal stenosis.