Newer guidelines to treat tuberculosis
As a part of the continuing medical education (CME) by PG Times, this article covers newer guidelines to treat tuberculosis (TB), which all doctors should know about.
The standardized treatment regimens are one of the pillars of the DOTS (directly observed treatment, short-course) strategy.
First Line Drugs: Isoniazid, Rifampicin, Pyrazinamide, Ethambutol and Streptomycin.
Second Line Drugs: Kanamycin, Ethionamide, Cycloserine, Capreomycin, Fluoroquinolones, Macrolides and Rifabutin.
Most DOTS regimens have thrice-weekly schedules and typically last for 6 to 8 months, with an initial Intensive phase and a Continuation phase.
Based on the nature/severity of the disease and the patients’ exposure to previous anti-tubercular treatments, RNTCP (Revised National Tuberculosis Control Programme) classifies tuberculosis patients in to two Treatment Categories.
1. New Cases
New Sputum Smear-positive,
New Sputum Smear-negative,
New Extrapulmonary Tuberculosis,
2H3R3Z3E3 + 4H3R3 — means Four drugs at Thrice-weekly schedule for 2 months Intensive phase and Two drugs at Thrice-weekly schedule for remaining 4 months Continuation phase.
2. Previously Treated Cases
Sputum smear-positive Relapse,
Sputum smear-positive Failure,
Sputum smear-positive Treatment after default
Others include patients who are Sputum Smear Negative or who have Extra-pulmonary disease who can have recurrence or resonance.
2H3R3Z3E3S3 + 1H3R3Z3E3 + 5H3R3E3 — Means 3 months Intensive phase + 5 months Continuation phase. Five drugs at Thrice-weekly schedule for initial 2 months followed by Four drugs at Thrice-weekly schedule for next 1 month Intensive phase and Three drugs at Thrice weekly schedule for remaining 5 months Continuation phase.
Doses of Individual Drug — H: Isoniazid (600 mg), R: Rifampicin (450 mg), E: Ethambutol (1200 mg), Z: Pyrazinamide (1500 mg), S: Streptomycin (750 mg)
1. Patients who weigh 60 kg or more receive additional Rifampicin 150 mg.
2. Patients who are more than 50 years old receive Streptomycin 500 mg.
3. Patients who weigh less than 30 kg receive drugs as per paediatric weight band boxes, according to body weight.
4. New categories includes former Categories I & III
5. Previously treated is former Category II