Mucobacterium tuberculosis

1. MYCOBACTERIUM
TUBERCULOSIS
By
Ihsanullah
11888

2. DESCRIPTION
 Mycobacterium tuberculosis is a non motile, acid-
fast, obligate aerobe.
 The bacilli are 2-4 um in length and have a very
slow generation time of between 15 and 20 hours.
 The cell wall of the mycobacterium is unique in
that it is composed mainly of acidic waxes,
specifically mycolic acids.
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3. HISTORY
 In South Africa, 99% of all TB infections in humans
are caused by Mycobacterium tuberculosis.
 On March 24, 1882, Dr. Robert Koch announced
the discovery of Mycobacterium tuberculosis, the
bacteria that causes tuberculosis (TB). During this
time, TB killed one out of every seven people living
in the United States and Europe.
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4. Mycobacterium tuberculosis
 Mycobacterium tuberculosis is a species of
pathogenic bacteria in the family
Mycobacteriaceae and the causative agent of
tuberculosis.
 Tuberculosis (TB) is an infectious disease usually
caused by Mycobacterium tuberculosis (MTB)
bacteria.
 Tuberculosis generally affects the lungs, but can
also affect other parts of the body.
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5. CONT…
 Mycobacterium tuberculosis is a acid fast bacteria,
which can form acid-stable complexes .
 All species of mycobacteria have ropelike
structures of peptidoglycan that are arranged in
such a way to give them properties of an acid fast
bacteria.
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6. CONT…
Many non pathogenic mycobacteria are components
of the normal flora of humans, found most often in dry
and oily locales.
The rods are 2-4 micrometers in length and 0.2-0.5
um in width
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7. CONT…
 Mycobacterium tuberculosis is the most important
of this group because it is responsible for
tuberculosis (TB).
 Acid-fast organisms like Mycobacterium contain
large amounts of lipid substances within their cell
walls called mycolic acids. These acids resist
staining by ordinary methods such as a Gram stain.
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8. TRANSMISSION
 The Mycobacterium tuberculosis bacterium causes
TB.
 It is spread through the air when a person with TB
(whose lungs are affected) coughs,
 sneezes,
 spits,
 laughs
 talks
 TB is contagious.
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9. Pathogenesis of MTB
 Infection occurs when a person inhales droplet
nuclei containing tubercle bacilli that reach the
alveoli of the lungs. These tubercle bacilli are
ingested by alveolar macrophages;
 M. tuberculosis , produce a type of spore known as
an endospore
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10. CONT…
 Upon host infection, Mycobacterium tuberculosis
secretes the tuberculosis necrotizing toxin (TNT)
into the cytosol of infected macrophages, leading
to host cell death by necroptosis.
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11. CONT…
 In addition, we do not understand the relationship
between M. tuberculosis in macrophages and
development of the granulomatous pathology
characteristic of M. tuberculosis infection.
 Therefore, a major goal of future studies will be to
understand the relationship between specific M.
tuberculosis products and intracellular survival
within macrophages.
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12. LATENT AND ACTIVE TB
● Latent TB:
● In this condition, you have a TB infection, but the bacteria
remain in your body in an inactive state and cause no
symptoms. Latent TB, also called inactive TB or TB
infection, isn't contagious.
● Active TB:
● This condition makes you sick and in most cases can spread
to others. It can occur in the first few weeks after infection
with the TB bacteria
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13. SIGNS AND SYMPTOMS
 Coughing that lasts three or more weeks
 Coughing up blood
 Chest pain, or pain with breathing or coughing
 Unintentional weight loss
 Fatigue
 Fever
 Night sweats
 Chills
 Loss of appetite
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14. CONT…
 Tuberculosis can also affect other parts of your
body, including your kidneys, spine or brain. When
TB occurs outside your lungs, signs and symptoms
vary according to the organs involved. For
example, tuberculosis of the spine may give you
back pain, and tuberculosis in your kidneys might
cause blood in your urine
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15. TREATMENT
 Conventional antitubercular therapy for at least 6
months including initial 2 months of HREZ (e.g.
isoniazid, rifampicin, ethambutol and
pyrazinamide) followed by 4 month HR is
recommended in all patients with abdominal
tuberculosis
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16. PRECAUTIONS
 VACCINES
 BCG
 (Bacillus camette guarine)
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17. Diagnosis
 Mantoux tuberculin skin test (TST) or the TB blood
test can be used to test for infection. Additional
tests are required to confirm TB disease. The
Mantoux tuberculin skin test is performed by
injecting a small amount of fluid called tuberculin
into the skin in the lower part of the arm.
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18. Procedure of Acid-Fast Stain
 Prepare bacterial smear on clean and grease free
slide, using sterile technique.
 Allow smear to air dry and then heat fix...
 Cover the smear with carbol fuchsin stain.
 Heat the stain until vapour just begins to rise (i.e.
about 60 C)....
 Wash off the stain with clean water.
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19. CONT…
 Cover the smear with 3% v/v acid alcohol for 5 minutes or until the smear is
sufficiently decolorized, i.e. pale pink.
 Caution: Acid alcohol is flammable, therefore use it with care well away from
an open flame.
 Wash well with clean water.
 Cover the smear with malachite green stain for 1–2 minutes, using the longer
time when the smear is thin.
 Wash off the stain with clean water.
 Wipe the back of the slide clean, and place it in a draining rack for the smear to
air-dry (do not blot dry).
 Examine the smear microscopically, using the 100 X oil immersion objective.
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