Tuberculosis Flashcards
TB caused by:
Mycobacterium tuberculosis complex
TB affects:
Pulmonary system (75%)
Extra-pulmonary system (25%)
It can be acute or?
Acute or chronic
Local or general
The disease is of great antiquity • Lesions have been found
in (the vertebrae of the Neolithic manin Europe, the Egyptian Mummies), perhaps as early as 3700 BC.
The disease increased during the ………….., but diminished as a result of the ……………
Industrial revolution
Increasing standard of living
Role of BCG and chemotherapy
Chemotherapy, BCG vaccination and Improved medical services accelerated the decline of the disease particularly in the developed world.
Worldwide, in 1993, TB had been declared by WHO a global emergency because:
• It has been neglected in the training programs of medical staff.
• Minimized by those responsible for controlling infectious diseases
• The co-epidemic of TB/HIV.
Currently, the TB incidence rate is levelling off or in decline. However, the total number of new TB cases is still rising slowly
because the case load continued to grow in the African, Eastern Mediterranean and South East Asian Regions
Reported annual incidence of TB (All forms) per 100.000 population in Libya 1973-2007.
• 1959, the prevalence was found 2-3% for pulmonary TB, up to 6% in children <5 years
• 1977, the prevalence of the disease was found 1.6%, (BCG coverage was 50% during infancy and 80% in school children).
• High incidence rate 40-60% was found among immigrants
TB is classified into :
Human & bovin + atypical
All are AFP
Most important investigation in TB
Sputum in the morning (stained using Ziehl-Neelsen method, Fluorescent microscopy, Serological and DNA tests are used).
Talk about appropriate conditions for TB
The bacilli can survive in the dark humid places for months or even years.
• They are highly susceptible to direct sunlight which kills them within minutes,.
• Heat can rapidly destroy them within 20 minutes at 60°C.
Mode of Transmission
Inhalation
Ingestion
Reservoir of human type
Man 🤷♂️
How does TB come by ingestion
Ingestion of unpasteurized or unboiled milk, or dairy product or uncooked meat of diseased cattle
(bovin tb)
Incubation period
Could be weeks or months depending upon the host -aget relationship and dose of infection.
Period of infectivity
It is communicable as long as the bacili are excreted by the (infected sick host) which may be months to few years
The progression of the disease in the host may depend on:
Genetic susceptibility
Physiological
Immunological
Environmental factors
Miscellaneous
Treatment and control of TB, is based on :
• Case finding
Isolation and effective treatment • of TB
• BCG vaccination
• Chemoprophylaxis
• Health education
Case funding by 4 techniques
• Sputum examination of smears for TB bacilli (ZN-stain) : method of choice
• Nucleic acid amplification (NAA) assay
• Photofluorography or mass miniature radiation (MMR)
• Tuberculin test : test of choice in areasls with low infection rate
Talk about tuberculin test
It is delayed immune response.
Few……… see you later
