Introduction
· So, tuberculosis is also called Koch’s disease.
· World TB day is observed on 24th March.
· Tuberculosis is the most common opportunistic infection in HIV patients.
· World TB day is observed on 24th March.
· Tuberculosis is the most common opportunistic infection in HIV patients.
· Extrapulmonary TB occurs in the Gastrointestinal tract, intestine, bone, skin, kidney, lymph glands (but not in hair and nail).
Themes by Year
2000: Forging new partnerships to stop TB
2001: DOTS: TB cure for all
2002: Stop TB, fight poverty.
2003: DOTS cured me – it will cure you!
2004: Every breath counts- Stop TB now!
2005: Frontline TB care providers: Heroes in the fight against TB
2006: Actions for life- Towards a world free of TB
2007: TB anywhere is TB everywhere
2008: I am stopping TB
2009: I am stopping TB
2010: On the move against TB: Innovate towards action
2011: On the move against TB: Transforming the fight towards elimination
2012: Stop TB in my lifetime Call for a world free of TB
2013: Stop TB in my lifetime Call for a world free of TB
Epidemiology Data
· World- 1/3rd population of the world is infected with Mycobacterium tuberculosis.
· In Nepal, 45% population is infected, 90,000 with active TB, 44,000 new cases per year, 8000-11000 die/year.
Distribution or Occurrence
· It is worldwide in distribution, more common in overcrowded rural areas than urban/city areas.
· In Nepal, it is more prevalent in the hilly region than in Terai.
Risk factors
· Overcrowding, poor sanitation, malnutrition, immune-compromised states like HIV, alcoholism, corticosteroids therapy, diabetes mellitus etc.
Causative Organism
· The causative organisms of TB are Mycobacterium tuberculosis and Mycobacterium bovis.
· It is a rod-shaped, small, gram-positive bacteria, measuring about1-4 µm in length.
· This aerobic bacterium damages the tissues by secreting toxin-tuberculin which forms tubercles.
· Being aerobic, it invades lungs where Oxygen concentration is high.
· Mycobacterium is acid-fast, non-capsulated and non-motile and facultative bacillus.
· Mycobacterium tuberculosis is also called Tubercle bacilli as it causes lesions called tubercles in the lungs.
· Mycobacterium tuberculosis usually causes pulmonary or lung TB.
· M. bovis usually causes abdominal TB due to the consumption of the non-pasteurized or infected milk.
· Mycobacterium tuberculosis usually causes pulmonary or lung TB.
· M. bovis usually causes abdominal TB due to the consumption of the non-pasteurized or infected milk.
Reservoir sources of Infection
· It is mostly restricted to infected persons but in some places, cattle also serve as reservoirs.
· It is mostly restricted to infected persons but in some places, cattle also serve as reservoirs.
· Mycobacterium can survive in dust for several months and in sputum for 20-30 hours.
Mode of Transmission
· This disease is transmitted by the throat and nasal discharge of the infected person and from the milk of the infected cattle.
· The infection may be direct or indirect contact (by air and droplet infection) and sputum, coughing, sneezing, shouting.
· One cough can produce about 3,000 droplet nuclei.
·TB primarily affects lungs (pulmonary tuberculosis) but can also affect other organs (extra-pulmonary tuberculosis) like abdomen (intestine), bone, kidneys, meninges, lymph nodes, but rare in nail and hair.
·TB primarily affects lungs (pulmonary tuberculosis) but can also affect other organs (extra-pulmonary tuberculosis) like abdomen (intestine), bone, kidneys, meninges, lymph nodes, but rare in nail and hair.
Incubation period: 3-6 weeks to many years.
Symptoms or Clinical Features of Pulmonary Tuberculosis
1) Fever in the evening, persistent coughing for about 2-3 weeks.
2) Loss of appetite (Anorexia), weight loss, weakness.
3) Sputum containing blood (haemoptysis), chest pain, night sweating, emaciation (thin), difficulty in breathing, dyspnoea (oxygen deficient), fatigue, tiredness.
4) In extrapulmonary tuberculosis, acute pain appears in affected parts of the body.
2) Loss of appetite (Anorexia), weight loss, weakness.
3) Sputum containing blood (haemoptysis), chest pain, night sweating, emaciation (thin), difficulty in breathing, dyspnoea (oxygen deficient), fatigue, tiredness.
4) In extrapulmonary tuberculosis, acute pain appears in affected parts of the body.
Diagnosis
· Diagnosis of TB is done by chest X-ray (cavities in lungs), sputum examination,
· Diagnosis of TB is done by chest X-ray (cavities in lungs), sputum examination,
· Tuberculin or Mantoux test to estimate the prevalence of infection in a population and gastric analysis.
· Ghon focus:
· It is a primary lesion usually subpleural, often in the mid to upper zones, caused by the infection of the Mycobacterium tuberculosis.
· It is a small area of granulomatous inflammation, only detectable by chest X-ray if it calcifies or grows substantially.
· Ghon’s complex:
· If the Ghon’s focus also involves infection of adjacent lymphatics and hilar lymph nodes, it is known as Ghon’s complex or primary complex.
· Ghon’s complex = Ghon’s focus + Hilar lymph nodes
· When a Ghon’s complex undergoes fibrosis and calcification, it is called a Ranke’s complex.
· Ghon’s complex = Ghon’s focus + Hilar lymph nodes
· When a Ghon’s complex undergoes fibrosis and calcification, it is called a Ranke’s complex.
Treatment
· Treatment is done by: (Remember PRISE)
· Pyrazinamide (Side effect is Jaundice),
· Rifampicin (Side effect is Jaundice),
· Isoniazid (Important side effect is peripheral Neuritis which can be prevented and treated by Pyridoxine),
· Streptomycin (Bactericidal- Kill bacteria)
· Ethambutol (Bacteriostatic-Inhibit multiplication of bacilli)
· Streptomycin is the only injectable, others are oral.
· Ethambutol is not prescribed in children as it causes colour blindness.
· Ethambutol (Bacteriostatic-Inhibit multiplication of bacilli)
· Streptomycin is the only injectable, others are oral.
· Ethambutol is not prescribed in children as it causes colour blindness.
DOTS (Directly Observed Treatment Short Course)
· Successful implementation of DOTS (Directly Observed Treatment Short Course) through the country by the National TB Centre.
· Successful implementation of DOTS (Directly Observed Treatment Short Course) through the country by the National TB Centre.
· It was introduced in April 1996 and extended to 75 districts by April 2001.
· The programme has benefited greatly from government commitment, community support and assistance from a range of both international agencies and NGOs.
· It is estimated that 60,000 TB deaths will be prevented by the DOTS programme in Nepal over the next five years.
· DOTS programme was developed by IUATLD (International Union Against Tuberculosis and Lung Disease).
Prophylaxis or Preventive Measures
1) Health education regarding the disease, mode of transmission, and prevention in all the communities and school students.
2) Timely diagnosis and treatment of infected people.
3) Immunization by BCG (Bacillus Calmette Guerin) vaccine to the non-infected persons. This vaccine was developed by two French Scientists Calmette and Guerin from bovine Tubercle bacilli of cattle in 1921 AD.
4) Pasteurization of milk prevents transmission of disease from cattle to man.
5) Good ventilation reduces the transmission of TB. Sunlight is the source of the UV rays that can kill TB bacilli. So, rooms and wards should have large windows accessible to sunlight.
· In hospitals and other places, ultraviolet overhead light is used to prevent the spread of the disease.
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