Tuberculosis – an overview Tuberculosis commonly referred to as TB, is an infectious disease of great significance all over the world. It is currently one of the important life threatening infections in AIDS patients with dual infection (HIV and TB). Current statistics suggest that about one third of the world’s population (about two billion people) carry the bacterium, even though they may not always manifest disease symptoms. With Asia and Africa having the highest number of TB patients, the need for improving awareness about this infection has never been as urgent.
Infectious agent & disease processMycobacterium tuberculosis, is the bacterium responsible for this deadly scourge. Discovered by Robert Koch (1882) its tough lipid rich cell walls enable it grow and multiply steadily within the body while evading antibiotic action. This also aids survival of the bacterium for prolonged periods of time sometimes leading to development of drug resistant forms. Various combinations of drugs (Multi drug regimens) have been developed to combat drug resistant forms.
The most commonly affected organs (in decreasing order of incidence) are the lungs, tonsils, lymph nodes of the neck, intestines, bones, joints, kidneys and meninges (layers covering the brain).
High risk groupsGroups that are more susceptible to tubercle infection include children and young adults, contacts of patients with active tuberculosis and patients with low immunity (AIDS patients, patients taking anti cancer drugs, diabetics, etc). Since the main route of spread is via respiratory droplets (during coughing) people living in overcrowded conditions (military recruits, underprivileged indigent populations) have an increased risk of contracting the infection.
PreventionBacille Calmette –Guerin (BCG) vaccine is usually administered in developing countries to all new born children. This is an extremely useful preventive measure in areas with high incidence of TB.
Diagnosis and treatment Mass miniature radiography (MMR) commonly known as the X-Ray of the chest is performed as a screening test along with sputum smear test (using saliva) and the tuberculin skin test (Mantoux test) in suspicious cases. A combination of these three tests is recommended in high risk cases to identify and start treatment in positive cases.
Directly observed treatment, short course (DOTS) is currently an international strategy to enable thorough treatment of infected cases. Here, a health care worker personally supervises drug intake by the patient, to prevent skipping or partial drug dosage which could eventually lead to drug resistance and ultimately death of the patient.
Some warning signs of tubercular infectionUnexplained weight loss, low grade fever during evening, loss of appetite, excessive sweating and coughing are some of the warning signs of infection. If any of these symptoms persist for more than a few days it would be wise to consult a physician for evaluation.
In view of the recent ‘TB day’ on March 24th, marked especially for creating global awareness about tuberculosis, it is the responsibility of each one of us to contribute in our own way to the eradication of this killer disease. Community health education and dissemination of information about the disease can be used by everyone as cheap, cost effective tools to add impetus to the global movement against tuberculosis.
- Dr.Sarika