Transcript History,Epidemiology,Reason for increase incidence,Transmission

Pulmonary tuberculosis
DR. Yousef Noaimat MD.FCCP
Consultant in pulmonary and internal
medicine.
History
• Tubercular decay has been found in the spines
of Egyptian mummies.
• Pictured: Egyptian mummy in the British
Museum
Epidemiology
• According to the World Health
Organization (WHO), nearly 2 billion
people—one third of the world's
population—have been exposed to the
tuberculosis pathogen
• Annually, 8 million people become ill with
tuberculosis, and 2 million people die from
the disease worldwide
• World TB incidence. Cases per 100,000; Red => 300,
orange = 200–300, yellow = 100–200, green = 50–100,
blue =< 50 and grey = n/a. Data from WHO ,2006
Reason for increase incidence
• HIV infections and the neglect of TB
control programs
• drug-resistant : from 2000 to 2004, 20% of
TB cases being resistant to standard
treatments and 2% resistant to second-line
drugs
• Lack of access to health care
• Poverty
• Definition :Pulmonary tuberculosis (TB) is a contagious
bacterial infection that mainly involves the lungs, but may
spread to other organs caused by the Mycobacterium
tuberculosis and Mycobacterium bovis
• In the United States, most people will recover from
primary TB infection without further evidence of the
disease. The infection may stay non active for years and
then reactivate.
• Most people who develop symptoms of a TB infection
first became infected in the past. However, in some
cases, the disease may become active within weeks
after the primary infection
Transmission
• cough, sneeze, speak, they expel infectious
aerosol droplets 0.5 to 5 µm in diameter. A single
sneeze can release up to 40,000 droplets.Each
one of these droplets may transmit the disease,
since the infectious dose of tuberculosis is very
low and the inhalation of just a single bacterium
can cause a new infection
• Transmission can only occur from people with
active — not latent
• When the disease becomes active, 75% of
the cases are pulmonary TB
• the other 25% of active cases, the
infection moves from the lungs, causing
other kinds of TB
Clinical presentation
The primary stage of the disease usually doesn't have
symptoms. When symptoms do occur, they may include:
• Cough heamoptysis
• Excessive sweating, especially at night
• Fatigue
• Fever
• Unintentional weight loss
Other symptoms that may occur with this disease:
• Breathing difficulty
• Chest pain
• Wheezing
Examination
• Examination may show:
• Clubbing of the fingers or toes (in people
with advanced disease)
• Enlarged or tender lymph nodes in the
neck or other areas
• Fluid around a lung
• Unusual breath sounds (crackles)
Diagnosis
• Sputum examination and cultures (ZN STAIN)
how can I take a good sample?
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Chest x-ray
Chest CT scan
Bronchoscopy
tuberculin skin test
Gastric aspiration?
The main problem with tuberculosis diagnosis is the difficulty in
culturing this slow-growing organism in the laboratory (it may take 4
to 12 weeks for blood or sputum culture
Mantoux tuberculin skin test
• polymerase chain reaction detection of
bacterial DNA, and assays to detect the
release of interferon gamma in response
to mycobacterial proteins such as ESAT
These are not affected by immunization or
environmental mycobacteria ,so generate
fewer false positive results
Treatment
• Latent TB treatment usually uses a single antibiotic
• People with latent infections are treated to prevent them
from progressing to active TB disease later in life.
However, treatment using Rifampicin and Pyrazinamide
is not risk-free. The Centers for Disease Control and
Prevention (CDC) notified healthcare professionals of
revised recommendations against the use of rifampin
plus pyrazinamide for treatment of latent tuberculosis
infection, due to high rates of hospitalization and death
from liver injury associated with the combined use of
these drugs
Treatment
• while active TB disease is best treated
with combinations of several antibiotics, to
reduce the risk of the bacteria developing
antibiotic resistance
• The two antibiotics most commonly used
are rifampicin and isoniazid
Treatment
• Initial phase 8 WKS:
• rifampicin +isoniazid +PYRAZINAMIDE
• If resistant possible add ethmbutol or
sterptomycin
• Give pyridoxine throughout treatment
• Continuation phase (4month)
• rifampicin +isoniazid+ pyridoxine
Treatment
When can I say treatment failure?
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Treatment failure is defined by
+ culture after 3 months
+AFB stain after 5 months
And should be treated by adding 2 more
drug
Treatment
• Main side effect
• Rifampicin: hepatitis (small raise of ASTis
acceptable . Stop if biliurubin raise)
• Isoniazid: hepatitis. Neuropathy
• ethmbutol: optic neuropathy
• PYRAZINAMIDE: hepatitis
(contraindicted in gout)
Prevention
• identified people with TB and their
contacts are and then treated
• children are vaccinated to protect them
from TB. Unfortunately, no vaccine is
available that provides reliable protection
for adults
Thank you