The Study Of Biofilm Formation Of Mycobacterium Tuberculosis In The Interface Of Implant

【Objection】The purpose is to investigate the feasibility and safety of one-stage debridement and internal fixation or artificial joint prosthesis to treatment active bone and joint tuberculosis. We study the adhesion ability and the biofilm formation of mycobacterium tuberculosis on different implants interface, at the same time observe the influence of rifampin to biofilm formation of mycobacterium tuberculosis on implant interface. Which was taken out from patient’s body was observed. Biofilm formation on the implant interface which was taken out of tuberculosis lesions from patient’s body.【Method】Under sterile conditions, titanium, vitallium and polyethylene samples were randomly and respectively placed in Middlebrook H7N9 culture medium to be co-cultured with mycobacterium tuberculosis for 4 weeks. Then, one sample was taken out randomly and added rifampicin to the culture medium continue to co-culture for 2 weeks. To comparison of the adhesion ability of mycobacterium tuberculosis on different implant materials(titanium, vitallium, and polyethylene) and different interface(smooth, rough), the number of colonies in the unit area in the material interface was measured by scanning electron microscope before and after rifampicin intervention. And then observed the influence of rifampicin to the structure of mycobacterium tuberculosis biofilms. Meanwhile, biofilm formation of mycobacterium tuberculosis onto the implant interface which was taken out from patient’s body was observed.【Result】The number of colonies in the unit area was significantly more in the polyethylene group than in the vitallium group(P < 0.05) and the number of colonies in the unit area was significantly more in the vitallium group than in the titanium group before intervention(P < 0.05). After rifampicin intervention, the number of colonies adhered in the three kinds of implant interface was reduced significantly(P < 0.05). The adhesion ability of mycobacterium tuberculosis is different; because of the implant interface roughness is different. In the case of the same material, the rough surface was more prone to bacterial adhesion than the smooth surface. Interaction between implant interface and material properties are significant(P<0.05). There wereno biofilm formation of mycobacterium tuberculosis on the interface of titanium and vitallium. Mycobacterium tuberculosis can form biofilm in the polyethylene interface, but anti-tuberculosis drug rifampicin can inhibit and even destroy the biofilms. In tuberculosis lesions, scanty mycobacterium tuberculosis was found on the interface of titanium and vitallium by scanning electron microscope and form biofilm on the interface.【Conclusion】The adhesive ability of mycobacterium tuberculosis to different implants is affected by the material properties and interface state. It can be form biofilm on implant, but it has the selectivity and specificity. Anti-tuberculosis drug rifampicin could reduce the ability of mycobacterium tuberculosis adhere to implant,as well as it can be suppress and damage the biofilms. In tuberculosis lesions, mycobacterium tuberculosis cannot form biofilm on the interface of titanium and vitallium. Low adhesive and rarely form biofilm in the interface of implant is the important reason for the feasibility and safety of the technology of one-stage debridement and internal fixation or artificial joint prosthesis. The risk of postoperative recurrence of bone and joint tuberculosis may be not increased by selecting the prosthesis into the tuberculosis lesions on the premise of systemic and local use of anti-tuberculosis drugs.