摘要
Objective:The current study analyzed the chemoprophylactic effect of isoniazide on close contacts of patients with active tuberculosis and positive tuberculin skin tests(TSTs).Methods:A total of 1206 close contacts of patients with active tuberculosis and strongly-pos-itive TSTs were enrolled.The patients had chest X-ray examinations.Patients without tuberculosis and other diseases were divided into the following groups:90 patients in the prophylaxis group,who were given 300 mg of isoniazid qd(3-5 mg/kg for children)over a 10-month treatment course;and 89 patients in the control group without drug therapy.Both groups were followed for 10 years.Results:(1)There were 568 patients with negative results and 638 with positive results,includ-ing 445 with ordinarily-and moderately-positive results,and 193 with strongly-positive results(a positive rate of 52.9%[638/1206]and a strongly-positive rate of 16.0%[193/1206]).Fourteen tuber-culosis patients were identified(tuberculosis detection rate of 1.1%).(2)During the 3-year period of follow-up,there were 4 patients in the prophylaxis group and 12 patients in the control group who acquired tuberculosis(a morbidity rate of 4.7%[4/84]and 13.4%[12/89],respectively),and the dif-ference was statistically significant(χ^(2)=3.916,P=0.048).Six patients in the prophylaxis group,all of whom were children,discontinued medication use during the course of treatment due to adverse drug reactions,for an adverse drug reaction occurrence rate of 6.6%(6/90),a medication completion rate of 93.3%(84/90),and a 3-year protection ratio of 64.6%.(3)During the 4-6 year period,there were two patients in the prophylaxis group and three patients in the control group who acquired tubercu-losis(a morbidity rate of 2.5%[2/78]and 4.1%[3/73],respectively),two in the prophylaxis group and four in the control group who were lost to follow-up(a loss to follow-up rate of 2.5%[2/80]and 5.1%[4/77],respectively),and the difference was not statistically significant(χ^(2)=0.006,P=0.940;χ^(2)=0.215,P=0.643).(4)During the 7-10 year study,there was one patient in the prophylaxis group and two patients in the control group who acquired tuberculosis(a morbidity rate of 1.3%[1/72]and 3.1%[2/64],respectively),and four in the prophylaxis group and six in the control group who were lost to follow-up(a loss to follow-up rate of 5.2%[4/76]and 8.5%[6/70],respectively),and the dif-ference was not statistically different(χ^(2)=0.011,P=0.918;χ^(2)=0.176,P=0.675).(5)Within 10 years,there were 7 patients in the prophylaxis group and 17 patients in the control group who acquired tu-berculosis(a morbidity rate of 8.3%[7/84]and 21.5%[17/79],respectively;χ^(2)=4.770,P=0.029),and 6 in the prophylaxis group and 10 in the control group were lost to follow-up(the loss to follow-up rate was 7.1%[6/84]and 11.2%[10/89],respectively;χ^(2)=0.863,P=0.353).Conclusion:Close contacts of patients with active tuberculosis are at high-risk for acquir-ing tuberculosis.It is safe and effective for patients with strongly-positive TST results to undergo isoniazid chemoprophylaxis for 10 months.
