TuberculosisIt is an acute or chronic infectious disease of the lungs but can also affect other

parts of the body including bones joints and brains. It is characterized by pulmonary infiltrate and by the formation of granulomas with caseation, fibrosis and cavitation

Causative organismTB is caused by the bacterium Mycobacterium tuberculosis.

Not everyone who is infected with the TB bacteria develops the disease. These people may not feel ill and may have no symptoms. They do not also spread the

infection to others. Their immune system “walls off” the tuberculosis bacilli which, protected by a thick waxy coat can lie dormant for years.

Incubation periodFrom infection to demonstrable lesion, about 4 to 12 weeks (3months); to progressive pulmonary or extra pulmonary tuberculosis may be years.

IncidenceIt is twice as common in men than in women. It is highest in people who live in crowded, poorly ventilated, unsanitary conditions such as in prisons. Also common in people who are immune compromised such as in HIV infected individuals.Mode of transmissionDroplet infection, when an infected person coughs, sneezes, laughs, talk or spit.Individuals at risk• People in contact with an infected person• Individuals who have had TB before

• People with multiple sexual partners• Drug and alcohol abusers• Patients in mental institutions• Those receiving immunosuppressants and corticosteroidsForms Pulmonary tuberculosis which affects the lungs and very commonExtra pulmonary tuberculosis: this is less common and affects the spine, lymph nodes, brain and meninges, kidneys, intestines, etc.

signs and symptoms• Mucopurulent cough or blood stained sputum• Cough that lasts for more than 3 weeks• Chest pain• Weakness• fatigue• Mild /low grade fever• Loss of weight• Loss of appetite chest pain • Evening or night sweats

diagnosis• Chest x-ray • Sputum culture and sensitivity test• Tuberculin test( indicates that patient have been infected with TB at some point

but does not indicate active disease)• Full blood count.

ManagementThey are placed on four drug regimen. These are• Isoniazid• Ethambutol• Rifampicin• Pyrazinamide

prevention