Management of Anti-Tuberculosis Treatment After Drug-Induced Liver Injury

Introduction to Reintroduction Protocol

For a patient with improved liver function tests after DILI, the recommended approach is to reintroduce anti-TB drugs sequentially, starting with ethambutol and streptomycin, then adding rifampicin followed by isoniazid, with careful monitoring of liver function, as suggested by the American Thoracic Society and the Infectious Diseases Society of America 1, 2

The patient experienced DILI while on standard anti-TB treatment and was switched to a less hepatotoxic regimen, which led to improved liver function tests, indicating resolution of acute hepatotoxicity 2
The patient now requires reintroduction of effective anti-TB therapy to ensure adequate treatment of tuberculosis, according to the American Journal of Respiratory and Critical Care Medicine 1, 3

Continue ethambutol and streptomycin as these are less hepatotoxic and well-tolerated by the patient, as recommended by the Clinical Infectious Diseases journal 1, 2
Begin with rifampicin at 75 mg/day for 2-3 days, and if no reaction occurs, increase rifampicin to 300 mg/day for 2-3 days, and further increase to 450 mg (<50 kg) or 600 mg (>50 kg) according to patient's weight, as suggested by Thorax 2
After 2-3 days of full-dose rifampicin without reaction, add isoniazid at 50 mg/day, and if no reaction occurs, increase isoniazid to 300 mg/day after 2-3 days, as recommended by Thorax 2

Monitor liver function tests weekly for the first 2 weeks after each drug reintroduction, and continue monitoring every 2 weeks for the first 2 months, as suggested by Thorax 2
Educate patient about symptoms of hepatotoxicity and instruct to stop medication and seek medical attention if these occur, according to the American Journal of Respiratory and Critical Care Medicine and Praxis Medical Insights 2, 4

If liver enzyme values rise, stop the most recently added hepatotoxic drug, and if the patient is not acutely ill and TB is non-infectious, pause treatment until liver function normalizes, as recommended by Thorax and the American Journal of Respiratory and Critical Care Medicine 2, 3

If pyrazinamide cannot be tolerated, use isoniazid, rifampicin, and ethambutol for 2 months, followed by isoniazid and rifampicin for 7 months, as suggested by the Clinical Infectious Diseases journal and the American Journal of Respiratory and Critical Care Medicine 1, 3
If isoniazid cannot be tolerated, use rifampicin, pyrazinamide, and ethambutol with or without a fluoroquinolone for at least 6 months, according to the American Journal of Respiratory and Critical Care Medicine 3
If both isoniazid and pyrazinamide cannot be tolerated, use rifampicin and ethambutol with a fluoroquinolone for 12-18 months, as recommended by the Clinical Infectious Diseases journal and the American Journal of Respiratory and Critical Care Medicine 1, 3
If all hepatotoxic drugs cannot be tolerated, use ethambutol with a fluoroquinolone, cycloserine, and injectable agent for 18-24 months, as suggested by the Clinical Infectious Diseases journal and the American Journal of Respiratory and Critical Care Medicine 1, 3

Patients with pre-existing liver disease are at higher risk for DILI and require more careful monitoring, according to the Clinical Infectious Diseases journal and Praxis Medical Insights 1, 4
Streptomycin should be administered as 15 mg/kg 2-3 times weekly in the long term to minimize toxicity, as recommended by the Clinical Infectious Diseases journal 1