Study of Safety and Efficacy of Different Regimes of Reintroduction of Anti-TB Drugs in Anti-TB Drugs Induced Liver Damage

Tuberculosis continues to be a major health problem in both the developing and developed countries because of its resurgence in the immunosuppressed patients. Short course chemotherapy containing isoniazid, rifampicin and pyrazinamide has proved to be highly effective in the treatment of tuberculosis. One of its adverse effect is liver damage which is the most common side effect leading to interruption of therapy.

There is lack of consensus guidelines for treatment of anti-TB drug induced liver damage Whether the re-introduction should take place with all the drugs given together in full doses (which reduces the chance of resistance and cost to the patient) or in a phased manner. There is lack of studies which compared different regimens of re-introduction of anti-TB drugs.

In this study, we will study three regimes of re-introduction of hepatotoxic anti-tuberculosis drugs (Rifampicin, Isoniazide, Pyrazinamide). These are potent anti-tuberculosis medications and need to be restarted in patients who developed liver toxicities attributed to these medications and became normal when these medicines were stopped. At the time of re-introduction the patients will be randomized in 3 groups.

• First group will receive Isoniazide(5mg/kg/day), Rifampicin(10mg/kg/day) and Pyrazinamide(25mg/kg/day) in full doses on day 1 and continued further.
• second group will receive Rifampicin(10mg/kg/day) in full dose on day 1 and continued, Isoniazide(5mg/kg/day)in full dose on day 8 and continued, Pyrazinamide(25mg/kg/day)on day 15 and continued.
• Third group will receive 100 mg/day of Isoniazide on day 1 which is gradually increased to maximum dose (5mg/kg/day) by day 4 and continued. Rifampicin is introduced on day 8 in a dose of 150 mg/day which is gradually increased to maximum dose (10mg/kg/day) by day 11 and continued. Pyrazinamide is introduced on day 15 in a dose of 500mg/day which is gradually increased to maximum dose (25mg/kg/day) by day 18 and continued.

All the three groups will be monitored for three months by analyzing weekly liver function tests. Any difference in the morbidity, deranged liver function or any other adverse effects will be monitored and treated appropriately.

Inclusion criteria

• A rise of five times the upper limit of the normal levels (50 IU/L) of serum aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT)
• A rise in the level of serum total bilirubin level > 1.5mg/dl
• Any increase in serum AST and or ALT above pretreatment values together with anorexia, nausea, vomiting and jaundice
• Absence of serological evidence of infection with hepatitis viruses A,B,C,or E
• Normalization of liver function tests after withdrawal of antituberculosis drugs For diagnosis of anti-TB drugs induced hepatitis, criteria 1 or 2 or 3 should be present along with criteria 4 and 5.

Exclusion criteria

• Patients with serological evidence of acute viral hepatitis A,B,C,or E and carriers for HBV & HCV
• Age < 15 year and age > 65 years
• HIV positive patients
• Presence of chronic liver disease or cirrhosis
• Co-administration of other potential hepatotoxic drugs (methotrexate, phenytoin, valproate)
• Chronic alcoholics who consume > 48 g of alcohol/day for at least one year
• Pregnant women
• Subjects not giving consent