1.Surveillance of drug resistance to Mycobacterium tuberculosis in Hainan Province, 2018-2022
HUANG Jingjing ; KE Qianyu ; HOU Ping ; LUO Xingxiong
China Tropical Medicine 2024;24(1):102-
Objective To understand the drug resistance surveillance situation of Mycobacterium tuberculosis in Hainan Province from 2018 to 2022, analyze the drug resistance status and trends of Mycobacterium tuberculosis in Hainan Province, and provide scientific basis for the formulation of tuberculosis prevention and treatment strategies. Methods A total of 2 481 sputum culture-positive isolates from pulmonary tuberculosis patients collected from 2018 to 2022 were subjected to strain identification and drug sensitivity testing. Strain identification was performed using the p-nitrobenzoic acid (PNB) inhibition test, and the sensitivity test for six anti-tuberculosis drugs, including Rifampicin (RFP), Isoniazid (INH), Streptomycin (SM), Ethambutol (EMB), Ofloxacin (OFX), and Kanamycin (KM), was conducted using the solid culture proportion method. The drug sensitivity results were statistically analyzed. Results Of the 2 481 isolates, 2 211 were identified as Mycobacterium tuberculosis complex (MTBC). The overall drug-resistance rate was 19.9% (441/2 211). The drug resistance rates for initial-treatment and retreatment patients were 15.7% (271/1 729) and 35.3% (170/482) respectively, with a statistically significant difference (χ2=90.65, P<0.01). The mono-resistance rate (MR) was 6.0% (132/2 211), with monoresistance rates of 5.6% (97/1 729) for initial-treatment patients and 7.3% (35/482) for retreatment patients, with no statistically significant difference (χ2=1.83, P>0.05). The overall poly-resistance rate (PR) was 4.1% (91/2 211), with polyresistance rates of 3.5% (61/1 729) for initial-treatment patients and 6.2% (30/482) for retreatment patients. The overall multidrug-resistance rate (MDR) was 8.0% (176/2 211), with multidrug resistance rates of 4.2% (72/1 729) for initial-treatment patients and 21.6% (104/482) for retreatment patients. According to the χ2 test, the retreatment group had significantly higher rates of polyresistance and multidrug resistance than the initial-treatment patient group, with statistically significant differences (χ2=6.94, P<0.01; χ2=155.98, P<0.01). The resistance rates to individual drugs in descending order were 11.6% (251/2 211) to INH, 11.4% (255/2 211) to RFP, 8.6% (191/2 211) to SM, 8.2% (181/2 211) to OFX, 4.0% (88/2 211) to EMB, and 1.6% (35/2 211) to KM. Conclusions The overall drug-resistance rate, poly-resistance rate, and multidrug resistance rate of Mycobacterium tuberculosis in retreatment patients in Hainan Province are higher than those in initial-treatment patients. Standardized treatment and management of TB patients are particularly important.
2.Spoligotyping and drug resistance analysis of 136 drug-resistant Mycobacterium tuberculosis strains in Hainan Province
HUANG Jingjing ; HOU Ping ; ZENG Xiangjie ; KE Qianyu ; LUO Xingxiong
China Tropical Medicine 2023;23(9):977-
Abstract: Objective In order to understand and master the prevalence of different genotypes and the rate of different drug-resistant Mycobacterium tuberculosis genotypes in Hainan Province, 136 drug-resistant Mycobacterium tuberculosis strains collected in Hainan province in 2022 were genotyped, and to provide scientific basis for tuberculosis prevention and control strategy in Hainan Province. Methods A total of 136 drug-resistant Mycobacterium tuberculosis strains were collected in Hainan Province. The clinical isolates were genotyped using the Spoligotyping technique, and the drug resistance rates of different genotypes of Mycobacterium tuberculosis were statistically analyzed. Results Among the 136 strains of drug-resistant Mycobacterium tuberculosis, 54.41% (74/136) belonged to the Beijing types, 27.94% (38/136) to non-Beijing types and newly identified genotypes accounted for 17.65% (24/136). The Beijing type included two genotypes, SIT1 and SIT269 genotypes, accounting for 52.94% (72/136) and 1.47% (2/136) respectively. Among the non-Beijing genotypes, the T type (T1, T2, T3) accounted for 21.32% (29/136), the U type accounted for 6.62% (9/136). Clustering analysis of genotyping results revealed two major clusters, Beijing type and non-Beijing type, as well as several scattered novel genotypes. Clustering analysis of Spoligotyping results classified the 136 drug-resistant strains into 3 clusters, with a clustering rate of 75.74% (103/136). The rates of mono-resistance (MR), poly-resistance (PR), multi-drug resistance (MDR), and other types of drug resistance in Beijing type and non-Beijing type were 41.89% (31/74), 13.51% (10/74), 24.33% (18/74), 20.27% (15/74) and 36.84% (14/38), 15.79% (6/38), 26.32% (10/38), 21.05% (8/38) respectively. Chi-square test results showed no statistically significant differences in drug resistance rates between the Beijing and non-Beijing types (P>0.05). Conclusion The genotype of Mycobacterium tuberculosis in Hainan Province showed genetic polymorphism, with the main epidemic genotype being SIT1 in the Beijing type. Monitoring of Mycobacterium tuberculosis in this genotype should be strengthened.