Research On The Relationship Between P.ances And Intervertebral Disc Degeneration

Background:Lumbar disc degenerated diseases are serious public health problems.Intervertebral disc degeneration is closely related to genetic factors,biomechanical factors,immune factors and biochemical factors.Recently,latent infection of P.ances and other low virulent anaerobic bacteria has been considered as a new pathogen for disc degenerationObjective and Innovation:This study was aimed at validating the etiological relationship between P.ances latent infection and disc degeneration and exploring the possible pathogenesis.For this aim,this study was designed to identify P.ances inside discs with histological method,to estimate the inflammation in discs and to establish a P.ances induced animal model of disc degeneration According to our known,the histological identification of bacteria in discs and the quantification of inflammatory mediators in patients' samples were firstly reported in this article.Moreover,the animal model was complementary to current theoryMethods:In the first part,the P.ances-positive non-pyogenic degenerated discs were identified with tissue culturing and 16S rDNA PCR and the histological observation was performed with HE stain and modified Brown-Brenn stain.In the second part,the chronic inflammation in discs was evaluated with quantification of TNF-?,IL-113,IL-6,IL-8,MCP-1,MIP-1? and IP-10,and counting of immunocytes in discs.Disc degeneration was examined with X-ray and MRI images.The comparison was made between P.ances-positive discs and P.ances-negative discs.In the third part,the disc degeneration model was caused by P.ances inoculation and a discitis animal model was induced by S.aureus infection.The differences were judged with MRI and histological observation Results:In this study,the P.ances positive rate in non-pyogenic degenerated discs was 26.9%with tissue culturing and 16S rDNA PCR.In part of P.ances-positive discs(7/15,46.7%),the microbe could be identified by histological method.In comparison to P.ances-negative discs,increasing concentration of IL-8(P=0.015)and MIP-1?(P=0.028),together with more neutrophils(P=0.043)were detected in P.ances-positive discs,Meanwhile,a lower average disc height(P=0.018)was found in P.ances-positive discs.Disc degeneration and Modic changes caused by P.ances-inoculation were confirmed with MRI and HE stain,which were different from the appearances of the discitis induced by S.aureusConclusion:The hypothesis that P.ances latent infection was a pathogen for disc degeneration was proved with histological identification and animal model.The possible pathogenesis was inflammatory reaction due to P.ances infection.Thus,the anti-bacterial therapy against P.ances may be an alternative treatment for disc degenerated diseases,such as low back pain and sciatica.