Case-Control Study On The Associations Of Immune Regarding Factors-sICAM-1, SIL-2R With The Risk Of Pulmonary Tuberculosis

[Objective]1.To explore the environment risk factors of pulmonary tuberculosis being occurred in Kunshan city.2.To explore its clinical significance by comparing the serum level of soluble intercellular adhesion molecule-1(sICAM-1),soluble interleukin-2 receptor(sIL-2R)in the smear positive and negative pulmonary tuberculosis(TB)patients and health Control.3.To study the linear correlation between the sICAM-1 and sIL-2R indexes among the whole subjects,smear negative TB cases,smear positive TB cases and controls,respectively,and to estimate the optimum cutting values of sICAM-1 and sIL-2R for diagnosing the TB patients perfectly.[Methods]1.Using case-control study,101 newly diagnosed TB patients aged 20～60 years old and being treated in Kunshan first people hospital and the township-level hospitals,Jiangsu province were investigated using structured-questionnaire by interview in-depth during April 1,2006 and December,31,2006.96 health controls were acquired using frequency-match method by ages(±3 yrs),sex,similar occupation and education level.Every subjects were asked to provide 5ml vein blood,which were centrifuged the serum being stored in -80℃ultra lower temperature refrigerator.It was used ELISA methodology to measure the serum level of the sICAM-1,sIL-2R indexes.Double inputting and checking the epidemiological and experiment data into the Epidata3 database. The statistical analysis was performed by SAS8.1and SPSS10.0 software,all the statistical tests were two-sided test at 0.05 significant level.The non-conditional logistic regression model was performed to explore the possible risk factors of TB.2.It was used one-way anova and q-test to compare the levels of sICAM-1,sIL-2R between the smear positive, negative newly diagnosed TB cases and health controls.Linear correlation coefficients were used to estimated the relationship between the sICAM-1,sIL-2R in total subjects, smear positive,negative newly diagnosed TB cases and health controls,respectively.The optimum cut values both considering the sensitivity and specialty for two indexes were estimated by ROC curve using the SPSS 10.0.[Results]1.Multivariate logistic analysis showed that more number of cigarettes smoking per day(OR=1.09,95%CI=1.0～1.2),less intake of fresh fruit before 5 years (OR=3.21,95%CI=1.7～6.0),lack of physical exercise(OR=7.67,95%CI=3.2～18.2),and ever being contacted with TB patient(OR=7.70,95%CI=1.8～33.2)were the risk factors of TB(P＜0.05).Eating less animal foods before 5 years(OR=1.84,95%CI=0.8～3.3),being living in not-well ventilation in house(OR=1.79,95%CI=0.7～4.3)and no BCG inoculation history(OR=2.20,95%CI=0.9～4.8)probably will increase the risk of TB at marginal statistically significance level.2.One-way anova analysis showed that there were significant difference for the serum level of sICAM-1(F=59.95,P＜0.0001), sIL-2R(F=13.83,P＜0.0001)between the 3 different groups.Smear positive TB patients carried highest serum level of sICAM-1,smear negative group ranked in second,and the health control showed the lowest level in the 3 groups(q-test,P＜0.05).For sIL-2R,there was no significant different between smear positive and negative groups,however whose serum levels were higher than health control's(q-test,P＜0.05).there were a significant linear positive correlation between theThere were significant correlations between sICAM-1,sIL-2R on the whole subjects (r=0.3566,P＜0.0001)and smear negative TB cases(r=0.4639,P=0.0017).However,no significance were found in smear positive TB cases(r=0.0472,P=0.7397)and controls (r=0.0077,P=0.9419).The optimum cut point for sICAM-1 both considering the sensitivity and specialty is in 364.04ng/ml(sensitivity,83.9%;specialty,83.0%),for the sIL—2R was estimated as 2.49ng/ml(sensitivity,63.9%;specialty,64.8%).[Conclusion]1.Stopping smoking,more physical exercise,improving the ventilation of house,eating more animal food and fresh vegetables and fruits,decreasing the chance of contacting with TB patient and taking parting the BCG inoculation could prevent from the TB.2.The study indicated that sICAM-1 and sIL-2R were involved in immune action of TB.With increasing of the quantity of sICAM-1,sIL-2R in serum,the ability for immune system of anti-TB will be retrained or decreased,which may be the cause of TB initiated and its development.Hence,there was clinical significance to determine the serious status of TB patients for sIL-2R(≥2.49ng/ml),especially for the sICAM-1(≥364.04ng/ml).