Abstract:

Objective: To analyze the drug resistance characteristics of 241 hospitalized patients with lymph node tuberculosis to guide individualized treatment. Methods: A retrospective analysis was conducted on the clinical data of 241 hospitalized patients with lymph node tuberculosis treated at Beijing Chest Hospital, Capital Medical University, from January 2016 to January 2024. The Mycobacterium microplate drug susceptibility testing technique was used to test and analyze the drug susceptibility test results of Mycobacterium tuberculosis isolated from 241 patients to 16 anti-tuberculosis drugs, including isoniazid (INH), rifampicin (RFP), ethambutol (EMB), streptomycin (Sm), rifapentine (Rft), rifabutin (Rfb), levofloxacin (Lfx), moxifloxacin (Mfx), kanamycin (Km), amikacin (Am), capreomycin (Cm), prothionamide (Pto), para-aminosalicylic acid (PAS), para-aminosalicylic acid isoniazid (Pa), clarithromycin (Clr), and clofazimine (Cfz), as well as the differences in drug resistance patterns between primary and retreatment patients. Results: Among 241 patients, the overall drug resistance, monoresistance, multidrug resistance (MDR), polydrug resistance and pre-extensively drug-resistant (pre-XDR) rates to 16 anti-tuberculosis drugs were 51.87% (125/241), 8.30% (20/241), 24.07% (58/241), 12.86% (31/241) and 10.37% (25/241), respectively. The overall resistance rate (62.50%,95/152), MDR rate (34.21%,52/152) and pre-XDR rate (16.45%,25/152) in retreatment patients were all significantly higher than those in primary patients (33.71% (30/89), 6.74% (6/89) and 0.00% (0/89), respectively), with χ² values of 18.639, 23.177 and 14.611 (continuity-corrected), all P<0.001. Among the 16 anti-tuberculosis drugs, drugs with highest resistance rates were INH (34.44%, 83/241), Sm (32.78%, 79/241), Rft (30.71%, 74/241), RFP (26.14%, 63/241), Pa (24.48%, 59/241), Rfb (22.41%, 54/241) and PAS (17.43%, 42/241). Among 58 patients with MDR-TB, the resistance rates to fluoroquinolones and second-line injectable anti-tuberculosis drugs were 43.10% (25/58) and 89.66% (52/58), respectively, and 24 patients (41.38%) were resistant to both classes simultaneously. In this subgroup, the resistance rate to fluoroquinolones (48.08%, 25/52)) and the rate of concomitant resistance to both fluoroquinolones and second-line injectable drugs (46.15%, 24/52)) in retreatment patients were significantly higher than those in primary patients (0/6 for both), with statistically significant differences by Fisher’s exact test (P=0.032 and 0.037, respectively). The cross-resistance rates among Rft, Rfb and RFP ranged from 72.97% (54/74) to 100.00% (54/54). A total of 44 MDR resistance combination patterns and 25 polydrug-resistance combination patterns were identified; the highest frequencies of individual MDR and polydrug-resistance pattern were 2.90% (7/241) and 2.07% (5/241), respectively, whereas 37 other MDR patterns and 22 polydrug-resistance patterns each had a frequency of 0.41% (1/241). Conclusion: Patients with lymph node tuberculosis exhibit a high overall rate of drug resistance; INH, Sm and rifamycin-class drug are the main drugs to which resistance occurs, and the patterns of multidrug and polydrug resistance are complex. These findings indicate a severe drug-resistance situation in lymph node tuberculosis, and clinical treatment should rely fully on drug susceptibility test to develop individualized and standardized anti-tuberculosis regimen.

Key words: Tuberculosis, lymph node, Drug tolerance, Microbial sensitivity tests, Epidemiologic studies