Isoniazid-specific T-cell Responses in patients with anti-tuberculosis drug related liver injury

Background A combination of isoniazid (INH), rifampicin, pyrazinamide and/or ethambutol (anti-tuberculosis drugs, ATDs) is commonly used for the treatment of tuberculosis. A significant clinical problem is that drug treatment is associated with mild elevations of liver enzymes that occasionally develop into severe liver injury. The culprit drug(s) and mechanistic basis of the reaction has not been defined. Thus, the aims of this study were to (1) explore whether drug-responsive T-lymphocytes were detectable in patients with ATD-related liver injury, (2) identify the drug(s) that activate T-cells and (3) characterize the nature of the T-cell response.