Bacteriological Investigation Of Clinical Spinal Tuberculosis And Study On Adherence Properties Of M.tuberculosis To Implant Material In Vitro

Objective1. To evaluate the clinical value of BACTEC MGIT 960 and PCR amplification of IS986,PCR-SSCP analysis of 16SrRNA for recovery and identification of Mycobacteria in spinal tuberculosis.2. To investigate the drug-resistance rate of MTB in spinal tuberculosis and evaluate the clinical value of detecting rpsL,katG,rpoB gene mutation by PCR-SSCP. To evaluate the effect of chemotherapy[3H RSE(Z)/6-15HRE(Z)] combined with surgical treatment in the management of drug-resistant spinal tuberculosis.3. To study the adherence of MTB onto the surface of several implant materials and evaluate the risk of instrumentation surgery in spinal tuberculosis from the point of bacterial adhesion.Methods1. 31 specimens obtained from patients of spinal tuberculosis were cultured by BACTEC MGIT 960 and L-J medium.Mycobacterium species of the clinical isolates were identified by PCR amplification of IS986 and PCR-SSCP analysis of 16SrRNA.2. All the clinical isolates of MTB were examined for the susceptibility to clinical antituberculosis drugs and the rpsL,katG,rpoB gene of each clinical strains was analysis by PCR-SSCP.A11 the patients were managed by antituberculosis therapy[3HRSE(Z)/6-15HRE(Z)] combined with surgical treatment.3. Different material discs were individually placed in different bacterial suspensions.The adherences of Mycobacterium tuberculosis and Staphylococcus epidermidis onto the different surfaces(smooth,rough)of different material discs (titanium alloy,stainless steel) were investigated by scanning electron microscopy(SEM) respectively.Results1. The recovery rates of BACTEC MGIT 960 and L-J medium were 83.87%,61.29% respectively.The average detection times of BACTEC MGIT 960 were 11.3 days,15.4 days earlier than that with the L-J medium(26.7 days). The genie identification of Mycobacterium species is rapid and accurate.The result is consistent with that of the tradition method.2. 18 MTB strains of 27 clinical isolates had resistance to one kind of the drugs.The drug resistant rate of SM,INH,RFP,PZA is 55.56%,44.44%,38.89%,16.67% and the mutation rate of rpsL,katG,rpoB in the drug resistant strains was 70%,50%,71.43% respectively.The gene mutation rate of the high concentration resistant strains is higher than that of the low concentration resistant strains. The chemotherapy combined with surgical treatment resulted in good outcome.3. The adherence of MTB onto the surface of two materials was very few than that of Staphylococcus epidermidis.The amount of adhesive bacteria on rough surface were more than that on smooth surface.Conclusion1. The application of BACTEC MGIT 960 system combined with the identification of the clinical isolates by molecular methods is an effective stragety for the bacteriological diagnosis of spinal tuberculosis.2. The traditional antituberculosis drug susceptibility test combined with the analysis of rpsL,katG,rpoB by PCR-SSCP was a useful method for detecting the drug susceptibility of MTB. Surgical therapy is beneficial for the treatment of drug resistant spinal tubercuculosis.3. The adherence properties of Mycobacterium tuberculosis to implant material was poor.This characteristics maybe one reason for performing instrumentation surgery in spinal tuberculosis safely.