Management is one person in the world who

Management
of Tuberculosis

General
overview of tuberculosis disease

1.1.1 Basic
facts of tuberculosis       

Tuberculosis (TB) is a common respiratory
disease that spread through one person to another and it is caused by bacteria
which is Mycobacterium tuberculosis
and occasionally by Mycobacterium bovis
and Mycobacterium africanum. The
bacteria also known as tubercle bacilli and it is under the group of acid-fast
bacilli. For the bacteria that is under the acid-fast bacilli group, when the
bacilli is stained with certain dyes and examined under the microscope, the
bacilli will look red. It will still remain the colour when it is washed with
acid and alcohol. Due to the difficulties to be washed out by the acid and
alcohol, this type of bacteria is considered as dormant in tissues and persist
for many years.

            That’s
why tuberculosis is considered as the disease that cause most of the death
cases after the HIV and heart diseases. The disease infects almost 33% of the
world’s population. 95% of tuberculosis cases and 98% of tuberculosis death are
in the developing countries. The age range of the people who have tuberculosis
disease is between 15-50 years old. Among the population in worldwide, Sub-
Saharan Afrika had the highest tuberculosis incidence rate and also the highest
annual rate of increase of cases. To make the condition becomes even worse,
according to WHO, there is one person in the world who will is newly infected
by the tuberculosis disease every second. The facts above really make us feel
shock.

Yet, have u even think about what
is main causes that lead to the prevalence of this disease. The main reason
that caused the prevalence of this disease is due to the mode and the source of
the infection. The mode of transmission of this TB is due to the air we
breathe. The sources of the tuberculosis disease include the patient with TB of
the lung, pulmonary TB (PTB) and also the one who is coughing, talking,
sneezing, spitting and singing. Just like what mention above, the bacteria that
cause TB is the tubercle bacilli. If a person who is infected by TB and he or
she is coughing, the tubercle bacilli will be come out in the air with tiny
infectious droplet nuclei. The infectious particles of the respiratory
secretions is usually less than 5 micrometers. That’s why we cannot seen
through properly. The dormant bacteria are kept by the body’s defence and it
will not show its clinical signs and signs. After the release of the droplet
nucleic, tubercle bacteria will be breathe in by other people, and then the
tubercle bacilli will start to multiply and become numerous in the body. If the
immune system of a person is weak and the bacteria tends to develop fast till
can overcome the immune system of the person, he or she for sure will develop
tuberculosis.

At any time, any age and anywhere,
a person can easily develop tuberculosis. The risk of getting the disease is
depending on the extent of exposure to the droplet nuclei, the immunity of a
person and also the time of the infection. The person can be infected past few
years but he or she may develop the disease recently. It is because if the
immune system of a person can suppress the disease, but due to some reason the
disease might be develop in certain stress condition. A person is more
susceptible to tuberculosis if he or she has HIV infection. Infants and
children are more susceptible to the disease because the immune system is not
mature. From the time the children are infected, usually he or she will usually
develop the disease two years afterwards. The most vital reason is due to
weakening immune resistance to beat with the disease. Other than this, physical
and emotional stresses may be triggered by progression of infection.

1.1.2
Pathogenesis of tuberculosis

            There
are two progress of the infection in tuberculosis which are primary infection and
also post-primary infection.

Primary
infection

            Primary
infection of tuberculosis is usually occurred on the people who haven’t got the
disease before. The incubation for the primary infection of tuberculosis is
usually 4-6 weeks starting from the infection of the disease. When the person
is being infected, the droplet nuclei will try to escape from the ciliary
action of the nose and try to embed in the alveoli of the lungs. If the droplet
nuclei is able to escape themselves from the ciliary action of the nose, they
will start to multiply in the alveoli of the lungs. The multiplication of the
bacteria in the alveoli will lead to several effects. The effects can be mild
till severe. The first outcome of the primary infection is that there is no
clinical outcome of the disease. This outcome is the most frequent as about 90%
of cases are under this outcome. At most of the time, the immune system of the
host will be automatically escape from the infection but the tuberculin skin
test is still positive because there is still infection in the host body.

If the immune system of the host is
not strong enough to resist with the infection, there will be some of the
symptoms and manifestations of the disease. There will be hypersensitivity
reactions occurs in the host. For example, erythema nodosum and phlyctenular conjuction
as well as dactylitis which is the inflammation and swelling of the feet and
hands. Besides, the lungs and also heart will be affected by tuberculosis.
Tuberculosis pneumonia and pleural infection are the complications of the
primary infection. Hyperinflation and collapse or consolidation of the lungs
are also the effects of TB. The most severe effects of TB is when the bacteria
is transmitted through the blood and becomes disseminated disease. Meningitis,
pericarditis and military disease are also outcome of the primary infection.

Post-primary
infection

            After
a latent period of months or even years, the primary infection will be
progressed to become post-primary tuberculosis. Furthermore, the post-primary
tuberculosis is happened when the dormant bacteria which is still alive after
the treatment of the primary infection and the bacteria is capable to multiply
themselves. Reactivation of the bacteria in the body will lead to a condition which
is called as reinfection. Reinfection is the condition in which the person will
has a repeat infection after the primary infection. The reasons why a person
will be getting reinfection is due to the weakening of the immune system by HIV
infection.

            The
immune response of the patient results in lesions that is characteristically
localized and this is often accompanied with the excessive tissue destruction
and cavitation. The transmission of the disease is more common and easy if the
person who is having the post-primary tuberculosis. Usually, the post-primary
tuberculosis will affect the lungs but the others part of the body will also
been affected. The manifestation of the lung will be more obvious in this case.
There are some of the characteristics of the post-primary tuberculosis. There
will be positive sputum smear and also lung destruction with cavitation. It is
usually no intrathoracic lymphadenopathy.

            The
effects of the post-primary tuberculosis has divided into two categories which
are pulmonary tuberculosis and extra-pulmonary tuberculosis. Pulmonary
tuberculosis has the following symptoms which are lung cavities, upper lobe
infiltrates, fibrosis, endobronchial and also progressive pneumonia. In
extra-pulmonary tuberculosis, there are some symptoms which are common and
there are also some of the manifestations are less common. Pleural effusion,
pericarditis, lymphadenopathy and also meningitis are the common symptoms of
post-primary infection. Gastrointestinal such as ileocaecal and also peritoneal
will be highly infected by tuberculosis too. In some cases that is less common,
we can observe the symptoms in which kidney and adrenal gland will be affected.
Empyema is one of the symptoms of the tuberculosis. Moreover, epididymitis and
orchitis which are the symptoms that are related to the male genital tract are
also the outcome of the extra-pulmonary tuberculosis. Extra-pulmonary
tuberculosis will also affect the female genital tract like endometrium and
tubo-ovarian. There will be also skin infection which include lupus vulgaris,
tuberculids and military.

Strategies
for the management of tuberculosis

            There
are many ways to manage tuberculosis include drug regimens and also vaccine
development. The purposes of managing tuberculosis are that we can prevent the
exacerbations of the disease and also we can totally remove the pathogens that
present in our body. The management of tuberculosis will also prevent the
transmission of the disease to other people and to prevent the recurrent
infection of the patient in the future. Tuberculosis is a well-known disease in
which it will affect the population in the world. The treatment for this
disease in term of drug already exists for more than 50 years old. Yet, why the
prevalence of the tuberculosis is not getting less instead it increases in a
high rate? This is because the management of the disease is not proper although
there are many drug regimens to treat the disease. In order to has a proper
anti-tuberculosis drug treatment, short-course chemotherapy (SCC) has to be
applied to the patients. In order to make sure that SCC is being carried out in
a proper manner, well managed TB control programme (NTP) has to be done.

            In the
standardized TB treatment, there are many treatment regimens available to treat
tuberculosis. Each country will apply different standard regimens to fulfil the
purposes of anti-TB drug treatment. The regimen for tuberculosis is the most
cost- effective of all the interventions and it is affordable for all walks of
life. There are certain drugs which are classified into first-line anti- TB
drugs and they have different modes of action, potency and dose applied. The drugs
include isoniazid (H), rifampicin (R), pyrazinamide (Z), thioacetazone (T),
streptomycin (S), and also ethambutol (E). These drugs are divided into two
main types which are bactericidal and bacteriostatic. Bactericidal drugs will
kill the bacteria while bacteriostatic will only slow down the production and
growth of the bacteria.

            Among
these drugs, all of them can be used in the intermittent use except thioacetazone.
Intermittent use of drugs mean that the drugs are consumed for a time and stop
for a time, then continues back. Thioacetazone cannot be used for intermittent purpose
and it has many side effects as it will cause toxicity to the people who
consume it and it will also cause severe skin reactions. Besides, it also has
low property of bacteriocidal action. Thus, it is now seldom be used. It is now
been substituted with other drug like ethambutol.

            The
above drugs that mention above act on different groups of bacilli. Tuberculosis
bacilli in a tuberculosis patient are divided into different groups such as
bacilli that are metabolically active, continuously growing in the host body.
There are also bacilli that stay inside cells such as macrophages. Moreover, there
is semidormant bacilli which will undergo occasional spurts of metabolic activity
and also dormant bacilli. Dormant bacilli will fade away and die away. Among these
bacilli, semidormant bacilli is the most difficult bacilli to remove. That’s
why the anti- tuberculosis treatment needs longer period to act against
different groups of bacilli. Isoniazid, rifampicin, pyrazinamide and streptomycin
are the drugs that classified as bactericidal drugs. Among these drugs,
isoniazid is the best to kill the metabolically active bacilli. It almost can
kill 90% of continuously growing bacilli. Nevertheless, isoniazid cannot kill
semidormant bacilli but rifampicin can. The bacilli that live inside the cells
like macrophages are killed by pyrazinamide. This bacilli are killed in the
acid condition inside the cells.

            The
table below shows how the drugs are being consumed in order to help to
eliminate the bacilli present in the body.

First
line anti-TB drugs

        Recommended dose (mg/kg of body
weight)

 

 

Intermittent
(3 times a week)

Daily

Isoniazid(H)

10

5

Rifampicin(R)

10

10

Pyrazinamide(Z)

35

25

Streptomycin(S)

15

15

Ethambutol(E)

30

15

Thioacetazone(T)

Not
applicable

2.5

 

Like what had mentioned above, semidormant bacteria
is the toughest bacilli to be removed through our body. Thus, rifampicin which
is able to remove this bacteria is considered to be the most effective drugs to
treat tuberculosis drugs. There are some of the bacilli that are considered to
be drug-sensitive bacilli in which they are resistant to certain drugs and they
are very difficult to be removed. This is why sometimes we need the combination
of the drugs in order to provide a wide range of bactericidal and
bacteriostatic action. Isoniazid and rifampicin are the best combination in order
to prevent the bacilli which will easily develop the resistance property to
some drugs. Stremptomycin and ethambutol are less effective if compared to
combination of isoniazid and rifampicin.