Effect of traumatic brain injury on the trough concentration of linezolid in patients with hospital-acquired pneumonia

Abstract

Abstract To investigate the effect of traumatic brain injury (TBI) on linezolid trough concentration (C min ) and Gram-positive bacteria eradication in patients with hospital-acquired pneumonia (HAP). HAP patients who treated with linezolid were collected and divided into TBI and non-TBI groups. Differences in the linezolid C min , Gram-positive bacterial eradication, clinical treatment success, and adverse reactions were analyzed between the two groups. A total of 177 patients were enrolled in the study, including 57 with TBI and 120 without TBI. After 1:1 propensity score matching (PSM), 46 patients with well-balanced baseline levels were enrolled. Linezolid C min and Gram-positive bacterial eradication rate were lower in TBI group than in non-TBI group [2.06 (0.89, 6.89) mg/L, 6.70 (3.09, 13.48) mg/L, P  < 0.001; 69.0% vs. 90.9%, P  = 0.029]. Linezolid-induced thrombocytopenia (LIT) and severe LIT occurred in fewer patients in TBI group than in non-TBI group (4.3% vs. 28.3%, P  = 0.005; 2.2% vs. 17.4%, P  = 0.035). The linezolid C min for the predicted eradication of Gram-positive bacterial was 1.62 mg/L. Further studies have found that the use of mannitol, glycerin fructose and high fluid intake and output may be responsible for the low C min of linezolid in TBI group. Patients in TBI group had lower linezolid C min and Gram-positive bacterial eradication rates compared with those in non-TBI group. A lower C min level may predict a decrease in Gram-positive bacterial eradication rates, and patients with concomitant TBI may need to explore higher linezolid doses.