XU Tao, LI Wenbin, SUN Qing, LIU Binbin, YU Yanyan, FANG Tanwei, TAN Yunhong
Objective To analyze the clinical epidemiology and drug resistance characteristics of hospitalized cases of lymph node tuberculosis (LNTB). Methods A retrospective survey method was used to collect the information about the surveyed hospitalized LNTB cases having a culture positive for Mycobacterium tuberculosis in Hunan Chest Hospital from January 2013 to March 2022. Data about the demographic, clinical characteristics and drug susceptibility test of the inpatients were collected from the hospital's electronic medical records. The clinical characteristics of the inpatients were descriptively analyzed, and χ2 test was used to compare the differences between groups. Results A total of 577 hospitalized cases of LNTB were collected, among which 373 (64.64%) cases were males and 352 (61.01%) cases farmers. The ages of the cases ranged from 3 to 83 years, withthe group aged 20-59 years accounting for the highest proportion (72.10%). The proportions of farmers in the groups of LNTB alone, LNTB alone combined with other extrapulmonary tuberculosis (LNTB-EPTB), and LNTB alone combined with pulmonary tuberculosis (LNTB-PTB) were all higher than those in other occupational groups, showing statistically significant differences (χ2=18.479, P=0.018). Most of the cases were reported in Changsha city and Shaoyang city, accounting for 20.10% and 14.04% respectively. There were 147 (25.48%) cases in the LNTB alone group, 350 (60.66%) cases in the LNTB-PTB group and 80 (13.86%) cases in the LNTB-EPTB group. The proportion of tuberculous lymph nodes in the neck was higher in the LNTB alone group than in the LNTB-PTB group and the LNTB-EPTB group (81.63% vs. 51.71%, 81.63% vs. 55.00%). There were statistically significant differences in the distribution of number of TB lesions among the three types of LNTB (χ2=547.539, P<0.001). Specifically, 97.28% of inpatients with LNTB alone had only one lesion, while 68.86% of inpatients with LNTB-PTB and 56.25% of inpatients with LNTB-EPTB had two lesions. For the initially isolated strains, the overall drug resistance rate to the four first-line anti-tuberculosis drugs was 26.00%, among which the rates of single drug resistance, multi-drug resistance (MDR) and poly-drug resistance were 9.36%, 12.48% and 4.16% respectively. The resistance rates to isoniazid (INH), streptomycin (SM), rifampicin (RFP), and ethambutol (EMB) were 20.62%, 18.37%, 13.34% and 6.07% respectively. The resistance rate to SM was higher in the group aged 20-59 years than in the group aged < 20 years and the group aged ≥ 60 years (21.39% vs. 10.26%, 21.39% vs. 10.84%), showing statistically significant differences (P<0.05). The resistance rates to SM, INH and RFP and the MDR rate were all higher in the western region than in the central and eastern regions. The rates of resistance to EMB and total drugs were higher in the western region than in the eastern and central regions. No statistically significant differences were found in the distributions of various types of drug resistance rates between genders and among occupations. Although there were differences in the drug resistance rates for six types of drug resistance among cases of farmers, students, cadres, the unemployed and other individuals, the differences were not statistically significant. Conclusions LNTB in Hunan province has unique clinical epidemiological and drug resistance characteristics, such as different high incidence regions, different sites, common multiple lesions, and serious drug resistance. The results of this study provide basic scientific data for more effective control of tuberculosis epidemic, and are conducive to improving the diagnosis, treatment, and prevention strategies of lymph node tuberculosis.
