Junjie Cheng,1,* Yuan Yuan,1,* Jinmeng Li,1 Ruoying Zhang,1 Xudong Fan,1 Zhirou Xu,2 Huirong Lin,3 Xinjun Cai,1 Mingfeng Zheng4 

1Department of Pharmacy, Zhejiang Hospital of Integrated Traditional Chinese and Western Medicine, Hangzhou, People’s Republic of China; 2Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, People’s Republic of China; 3Department of Pharmacy, Taizhou Cancer Hospital, Taizhou, People’s Republic of China; 4Department of Orthopaedics, Zhejiang Hospital of Integrated Traditional Chinese and Western Medicine, Hangzhou, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Mingfeng Zheng; Xinjun Cai, Zhejiang Hospital of Integrated Traditional Chinese and Western Medicine, Hangzhou, Zhejiang Province, 310003, People’s Republic of China, Email zmfyxz3@163.com; zjtcmcxj@zcmu.edu.cn

Purpose: Previous studies have indicated that the development of severe adverse events is associated with linezolid peak concentration (Cmax), but the factors affecting linezolid Cmax and evidences on therapeutic drug monitoring to anticipate toxicity in drug-resistant tuberculosis (DR-TB) patients have not been clarified clearly. This study aimed to explore the factors influencing linezolid Cmax and investigate the association between linezolid concentration and hematological toxicity.
Patients and Methods: This study included patients with drug-resistant tuberculosis treated with linezolid from January 2022 to September 2023. We analyzed the factors affecting linezolid Cmax using chi-squared and binary logistic regression. The diagnostic utility of linezolid Cmax in predicting hematological toxicity was evaluated using receiver operating characteristic (ROC) analysis.
Results: A total of 76 patients were enrolled in the study. 63.20% met the standard rates for linezolid Cmax. Age (P=0.036), weight (P=0.0016), and creatinine clearance (P=0.0223) significantly correlated with the Cmax. Hematological toxicity was observed in 46.05% (35/76) of patients, characterized by thrombocytopenia (31.58%, 24/76), anemia (6.58%, 5/76), and leukopenia (21.05%, 16/76). ROC curve analysis confirmed the predictive value of linezolid Cmax for thrombocytopenia with an area under curve of 0.728.
Conclusion: Suboptimal linezolid Cmax was prevalent among patients with DR-TB, with age, weight, and renal function emerging as influential factors. Elevated linezolid Cmax increases the risk of thrombocytopenia. Meticulous monitoring of linezolid Cmax is imperative during anti-DR-TB therapy to tailor treatment and mitigate hematological toxicity.

Keywords: linezolid, therapeutic drug monitoring, influencing factors, hematological toxicity