Environmental Pollution Status And Clinical Strains Of Non Tuberculous Mycobacteria In Nantong City

ObjectiveTo investigate the environmental pollution situation of non mycobaterium tuberculosis(NTM),the bacteria distribution and resistance to drugs of NTM and clinical isolates,and analysis the health hazards of NTM in Nantong city.Methods1)The survey of environmental pollution status of non mycobaterium tuberculosis(NTM)in Nantong city.Since 2016 to 2017,basic information of patients with mycobacterium infection were collected by a cross-sectional questionnaire in Nantong Sixth People’s Hospital.At the same time,clinical specimens and environmental specimens were collected from tuberculosis designated hospitals and public places in Nantong city.Roche culture method and BACTEC TB960 rapid culture method were used to culture mycobaterium,PCR-fluorescent probe was used to screen NTM.2)The bacteria distribution of NTM and clinical isolates.Gene chip method was used to confirm the bacteria.Drug sensitivity test was studied by absolute concentration method to determinate concentration of 8 two conventional drugs both in low and high level.Results1.Environmental samples in public or specific places were collected and cultured.68 of 236 cases were diagnosed as Mycobacterium tuberculosis,including 3 tuberculosis and 65 NTM.Positive rates of monitoring points top three were sewage before treatment from hospital,sewage from residential areas and sewage from markets.There was significant difference between the positive rate of NTM before and after sewage treatment(P<0.05),while high level of the positive rate of NTM after the treatment was still exist,around 21.4%.2.Cultivation showed that 702 patients had been diagnosed with Mycobacterium tuberculosis,including 62 NTM patients.The results from survey indicated that most patients with NTM were over 50 years old,and patients under 20 years old was rare,and,the age curve showed a single peak negative skewness distribution.Among all the patients with NTM infections,there were 42 men and 20 women,the male and female overall ratio was 2.1: 1.NTM in the household population proportion was obviously large than the mobile population(P<0.05).3.Results of the environmental and clinical specimens showed that the type of the NTM infection including m.intracellulare,Gordon,Mycobacterium abscess/turtle Mycobacterium,Mycobacterium Kansas,Mycobacterium avium and Mycobacterium fortuitum and Mycobacterium smegmatis in Nantong city.The most common infection in local region is Mycobacterium intracellular,accounted for 46.8%.NTM strains which isolated from the environment was nearly equal with clinical strains in this region.4.Drug susceptibility test of clinical strains showed that there were 62 strains had high resistance towards to first-line and second-line anti tuberculosis drugs,especially towards to rifampicin and ethambutol,the sensitive rate to ethambutol was 69.3%,which higher than others(P<0.05).And there were no sensitive strains.The result of drug sensitivity test of environmental strains had similar trend with clinical.Conclusion1.The environmental pollution status of NTM and natural distribution of NTM were investigated,which can promote people to strengthen the supervision of the environment and protect the environment.2.The individual differences and environmental risk factors of NTM infection were studied,which is of practical significance to control the source of infection and cut off the transmission route to prevent the outbreak of NTM in this area.3.There is a certain correlation between the distribution of NTM strains and clinical strains and the rate of drug resistance,which provides a scientific basis for the prevention and control of NTM disease in the future.