Preliminary Study On Social Behavior Factors Of TB Patients And Genotyping Of Mycobacterium Tuberculosis

Tuberculosis (TB) is a sort of the infectious disease heavily threatening people's health, and it had been effectively controlled during a certain period, but the incidence rate and the prevalence rate of tuberculosis gradually have been gone up in recent ten years, and drug resistant of tuberculosis, especially multi-drug resistant tuberculosis (MDR-TB) gradually increase year after year. It was reported by World Health Organization (WHO) that about 2 billions of the world's population were infected with Mycobacterium tuberculosis (M.TB), including 200 million patients of tuberculosis among them. Every year, new patient is more than 80 millions, and 2 millions died of tuberculosis.China was one of the higher disease burden countries of tuberculosis in the world. The results of epidemiologic investigation of TB in 2000 showed that approximately 0.55 billions infected TB, and the infection rate was 44.5%, there was 15 millions of smear positive patients and the prevalence rate of active tuberculosis was 367/1000000. In a word, Tuberculosis has become a serious public health problem.With the development of society and economy, social behavior of people influence on epidemic and transmission of TB. An irregular treatment of TB patients usually induces drug-resistant TB, especially MDR-TB. During treatment, Psychological state, social support and compliance of TB patients also affect the treatment effect of TB. Therefore, that social behavior factors were rightly understood has a far-reaching significance on curing and controlling of TB patients.Recently several years, with the development of molecular biology, the study of drug-resistant TB and genotyping has become the hotspot problem of TB research. It was reported that Beijing Family was a sort of M.TB having the most epidemic power and which was the main epidemic strain in Asia, North America and East Europe, especially in Russia.So, the studies on genotyping of M.TB, leading epidemic type and correlation between genotype and drug-resistance have an important significance on molecular epidemiology of TB and surveillance of drug resistant population.Objective The study is to comprehend basic condition of living and social behavior style of the TB patients in Sichuan Province and Anhui Province.To explore the main risk factors causing drug resistant TB and provide for reliable basis and clinical guidance for reasonable treatment, avoiding drug resistance and getting well quickly. Clinical isolates of TB in Sichuan Province are sampled for analysis of genotype and find out genotyping of M.TB, leading epidemic type and correlation between different genotype and drug resistance.Methods This study was conducted at the Institute of Tuberculosis Control and Prevention (ITCP) of Sichuan and Anhui Province, and 1489 patients of TB composed of 875 patients of Sichuan Province and 614 patient of Anhui Province were selected as systematic sampling. Using the methods of the qualitative and the quantitative research, the study object was investigated by questionnaires, which included the demographic characteristics, therapeutic behavior and risk factors of drug resistance, and a part of patients and doctors adopted the method of in-depth interview.124 clinical isolates were sampled from the TB patients of Sichuan province and identified by using biochemistry reaction method. The drug-susceptibility of the 124 clinical isolates was identified by absolute concentration method.The 124 clinical isolates were typed by MLVA typing method and spoligotying respectively and the results of the two genotypes were compared. Finally, using H₃₇Rv as reference strains, the data of the tests were dealt with cluster analysis by means of the BioNumerics 3.0 and the main epidemic strains and genotype were obtained. The relationship between the main epidemic strains and drug resistant TB was analyses by logistic regression.Results 1,The distributions of TB patients between Sichuan Province and Anhui Province had significantly differences among the age, degree of education and status of marriage and so on, but There were no difference among the gender, occupation, type of inhabitation, Area of inhabitation, income of per capita and area of per capita inhabitation.2,In the study, social supports of young TB patients were higher than the elder; The social supports of cadres and students of the TB patients were higher than the other TB patients; Objective support and subjective support of the male TB patients were higher than that of the female TB patients; The objective support and the subjective support of being marriage of the TB patients were higher than that of the other's. The TB patients having high school education or more had higher objective support.3,The TB patients of Sichuan Province and Anhui Province had been discriminated in different aspects, especially in work, social relation and psychology. Social stigma rates of the TB patients had drop trend along with increase of age and social stigma rate of new patients was higher than that of re-treat patients.4,The TB patients of floating population were mostly the age from 30 years to 50 years, and which of the acquired drug resistant rate and multiple-drug resistant rate were higher than that of permanent residents, respectively. The tuberculosis influenced the routine life of the patients at most, and less affected feeling of spouse and family members. Last year the economical cost of patients in hospital was significant higher than that of in ITCP.5,The qualitative research showed that the failure of treatment of tuberculosis is associated with man-made factors in the course of diagnosis and treatment of tuberculosis. Many factors influenced the hospitalizing behavior of the patients of TB, and the majority of TB patients had the diagnosis delay and the treatment delay, especially the TB patients in rural population and the urban poor population. Aged TB patients generally had longer delay time in the course of diagnosis and treatment of tuberculosis and poor compliance to treatment regimens. The TB patients were lacking in the knowledge about TB, and the responsibility of doctors and nurses was weakness. It was necessary to enhance the relationship between doctors and patients.6,The total drug resistant rate and multi-drug resistance rate of the TB patients in Sichuan Province and Anhui Province were 33.04% and 11.08%, respectively. The strains studied were inclined to multiple drugs simultaneously, but drug-resistance to RFP and INH was the most common resistance pattern.7,The main risk factors of drug resistance TB of Sichuan Province and Anhui Province were associated with the re-treat history, bad DOTS and poor compliance. In addition, any drug resistance of TB was associated with type of inhabitation and suffering years, and the Supply of anti-tuberculosis medication was also an important factor for MDR-TB.8,In the study, Drug susceptibility testing showed that the primary and acquired drug resistance rate were 9.13% and 23.91%, respectively. Drug-resistance rates to RFP, INH, SM and EMB were 19.4%, 19.3%, 9.1% and 7.7%, successively.9,DNA fingerprint of VNTR presented polymorphism to different strain or different locus, there was different allelic diversity at each VNTR locus, The ETR-B locus had the lowest diversity (0.309) and the Mtub21 locus has the highest diversity (0.575).10,The VNTR typing technique of twenty gene loci greatly advanced the power of discrimination, and it was a simple and rapid tool of which generated numerical genotypes. Thirty-seven genotypes were obtained from the study results, and clustering rates of each genotype had significant difference. Genotype (45.16%) having the highest clustering rate was the dominant VNTR pattern.11,In the VNTR results studied, the isolates between clustering genotype and single genotype had significant difference in the distribution of age, smear result and treatment history, and the acquired drug resistance rate of clustering genotype was higher than that of the single genotype's.12,124 isolates were classified Beijing Family and non- Beijing Family by Spoligotyping method. The acquired drug resistance rate of Beijing Family was higher than that of the non-Beijing Family's. There was better correlation between Spoligotyping method and VNTR typing technique.Conclusion 1,The TB patients of Sichuan province and Anhui Province had much sameness in main demography characteristics and social support of which were affected by age, gender, educational degree and occupation. The discrimination to the tuberculosis patients had already affected the treatment and management in a serious degree, and effective control measures should be taken to diminish these negative effects. The majority of TB patients of floating population were mostly work force of families, and the rate of ADR and the rate of MDR of TB patients of floating population were higher than that of other's.2,That the qualitative research was reasonable combined with quantitative research was to explore the behavioral factor influence of both doctor and patient to drug resistance TB. The TB patients both Sichuan Province and Anhui Province had a serous degree delay in the course of diagnosis and treatment, which influence upon cure rate of them, and drug resistance TB was one of the important cause inducing the failure of treatment. A well-functioning DOTS program and keeping good compliance is the precondition in reducing drug resistance TB and improving cure rate. It is the important measures of effectively resolving TB prevention and control to advance the knowledge about TB, to deal with the lack of the TB control worker and enhance the relationship between doctors and patients.3,Status of drug-resistant TB is quite serious in Sichuan Province and Ahui Province, and the strains studied tend to be resistant to multiple drugs simultaneously, especially resistance to INH and RIF. The order of drug resistant rate of anti-tuberculosis drug indicated that the TB treatment had each characteristic in Sichuan Province and Ahui Province.4,The patients of drug-resistant TB in Sichuan Province and Anhui Province were associated with social behavior factors of them. A well-functioning DOTS program and improving compliance are the effective measures to reduce drug resistance TB.To guarantee quality and quantity of supply medication and to improve first cure rate of TB patients have important meaning to decrease MDR-TB.5,The VNTR typing technique of twenty gene loci greatly advanced experimental sensitivity and power of discrimination. This is first study that data of VNTR typing and spoligotyping are obtained from M.TB strains of Sichuan province and indicate local dominant genotype: I type,II type and IIItype (Beijing Family). In Sichuan Province, The clustering genotype was some associated with drug resistant TB, and the genotype is one of the important factor associated with acquired drug resistance.