This occurs due to incomplete treatment, wrong dosage, poor quality of drugs, etc.
Tuberculosis is a disease caused by the bacteria, Mycobacterium tuberculosis. According to the World Health Organisation (WHO), in 2011, 87 lakhs people fell ill with TB and 14 lakh died. India constitutes a major burden country with 20% of all TB cases in the world. The government has been implementing the National TB control Programme since 1962. It was revamped and made the Revised National Tuberculosis Control Programme (RNTCP) in 1993. Under this new scheme, the DOTS (directly observed treatment, short course) strategy was adapted. Covering the whole of the country, diagnosis is primarily done by collecting sputum from the patient and examining it under microscope after making a smear.
This facility is being provided by specially trained laboratory technicians posted in peripheral hospitals at the 20-30,000 population level. If a patient diagnosed with TB, drugs are made available on the doorstep by a DOTS provider who keeps track of the patient.
The DOTS provider is a minimally trained person, who can be either a health staff member or a responsible villager. This treatment is thus under direct supervision. Four drugs are commonly used, Rifampicin, Isoniazid, Ethambutol and Pyrazinamide, in different combinations for six months. In some cases, injectible drug Streptomycin is used. The patient is followed up with sputum examination periodically to trace the progression of the disease.
All these services, including the drugs, are provided free of cost.
Multidrug resistant TB (MDR TB) is caused by bacteria that do not respond to at least Isoniazid and Rifampicin, the most powerful, first line anti-TB drugs. Drug-resistant TB occurs when drugs are not properly taken, like incomplete treatment, wrong dosage, wrong length of treatment, wrong combination, unavailability of drugs or poor quality drugs.
MDR TB diagnosis and treatment is difficult. First of all, the diagnosis needs culture and drug susceptibility testing entailing extensive laboratory work. There are only a few laboratories where this test can be done in India.
Once the problem is diagnosed as MDR TB, the second line drugs, which are 300 times costlier than the first line drugs, are prescribed. These are ofloxacin/levofloxacin, ethionamide, cycloserine, pyrazinamide, ethambutol and kanamycin. These drugs are used for 24 months in different combinations and have severe adverse events.
The government of India started DOTS Plus services (for diagnosis and treatment of MDR TB) in 2007 from Gujarat. Till date these services have been extended to 10 States.
There is an underlying fear that if these second line drugs also develop resistance then we will be left nowhere.
Take drug as prescribed — Adequate counselling to patient at the start of treatment on dosage
Continuous supply of quality drugs
Periodic follow-up to check for compliance and any adverse reactions
Take your drugs timely
Do not miss dose
Report any untoward incidents
It is difficult to diagnose and treat MDR TB. So we must make all efforts to prevent the emergence of resistant TB.
(The writer is Assistant Professor, Community Medicine, Kalinga Institute of Medical Sciences, KIIT University, Bhubaneswar. email: firstname.lastname@example.org)