Managementof TuberculosisGeneraloverview of tuberculosis disease 1.
1.1 Basicfacts of tuberculosis Tuberculosis (TB) is a common respiratorydisease that spread through one person to another and it is caused by bacteriawhich is Mycobacterium tuberculosisand occasionally by Mycobacterium bovisand Mycobacterium africanum. Thebacteria also known as tubercle bacilli and it is under the group of acid-fastbacilli. For the bacteria that is under the acid-fast bacilli group, when thebacilli is stained with certain dyes and examined under the microscope, thebacilli will look red. It will still remain the colour when it is washed withacid and alcohol. Due to the difficulties to be washed out by the acid andalcohol, this type of bacteria is considered as dormant in tissues and persistfor many years. That’swhy tuberculosis is considered as the disease that cause most of the deathcases after the HIV and heart diseases.
The disease infects almost 33% of theworld’s population. 95% of tuberculosis cases and 98% of tuberculosis death arein the developing countries. The age range of the people who have tuberculosisdisease is between 15-50 years old. Among the population in worldwide, Sub-Saharan Afrika had the highest tuberculosis incidence rate and also the highestannual 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 infectedby the tuberculosis disease every second. The facts above really make us feelshock. Yet, have u even think about whatis main causes that lead to the prevalence of this disease.
The main reasonthat caused the prevalence of this disease is due to the mode and the source ofthe infection. The mode of transmission of this TB is due to the air webreathe. The sources of the tuberculosis disease include the patient with TB ofthe lung, pulmonary TB (PTB) and also the one who is coughing, talking,sneezing, spitting and singing. Just like what mention above, the bacteria thatcause TB is the tubercle bacilli. If a person who is infected by TB and he orshe is coughing, the tubercle bacilli will be come out in the air with tinyinfectious droplet nuclei. The infectious particles of the respiratorysecretions is usually less than 5 micrometers.
That’s why we cannot seenthrough properly. The dormant bacteria are kept by the body’s defence and itwill not show its clinical signs and signs. After the release of the dropletnucleic, tubercle bacteria will be breathe in by other people, and then thetubercle bacilli will start to multiply and become numerous in the body. If theimmune system of a person is weak and the bacteria tends to develop fast tillcan overcome the immune system of the person, he or she for sure will developtuberculosis. At any time, any age and anywhere,a person can easily develop tuberculosis. The risk of getting the disease isdepending on the extent of exposure to the droplet nuclei, the immunity of aperson and also the time of the infection. The person can be infected past fewyears but he or she may develop the disease recently.
It is because if theimmune system of a person can suppress the disease, but due to some reason thedisease might be develop in certain stress condition. A person is moresusceptible to tuberculosis if he or she has HIV infection. Infants andchildren are more susceptible to the disease because the immune system is notmature. From the time the children are infected, usually he or she will usuallydevelop the disease two years afterwards. The most vital reason is due toweakening immune resistance to beat with the disease. Other than this, physicaland emotional stresses may be triggered by progression of infection. 1.1.
2Pathogenesis of tuberculosis Thereare two progress of the infection in tuberculosis which are primary infection andalso post-primary infection. Primaryinfection Primaryinfection of tuberculosis is usually occurred on the people who haven’t got thedisease before. The incubation for the primary infection of tuberculosis isusually 4-6 weeks starting from the infection of the disease. When the personis being infected, the droplet nuclei will try to escape from the ciliaryaction of the nose and try to embed in the alveoli of the lungs. If the dropletnuclei is able to escape themselves from the ciliary action of the nose, theywill start to multiply in the alveoli of the lungs. The multiplication of thebacteria in the alveoli will lead to several effects.
The effects can be mildtill severe. The first outcome of the primary infection is that there is noclinical 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 thehost will be automatically escape from the infection but the tuberculin skintest is still positive because there is still infection in the host body. If the immune system of the host isnot strong enough to resist with the infection, there will be some of thesymptoms and manifestations of the disease. There will be hypersensitivityreactions occurs in the host. For example, erythema nodosum and phlyctenular conjuctionas well as dactylitis which is the inflammation and swelling of the feet andhands.
Besides, the lungs and also heart will be affected by tuberculosis.Tuberculosis pneumonia and pleural infection are the complications of theprimary infection. Hyperinflation and collapse or consolidation of the lungsare also the effects of TB. The most severe effects of TB is when the bacteriais transmitted through the blood and becomes disseminated disease. Meningitis,pericarditis and military disease are also outcome of the primary infection. Post-primaryinfection Aftera latent period of months or even years, the primary infection will beprogressed to become post-primary tuberculosis.
Furthermore, the post-primarytuberculosis is happened when the dormant bacteria which is still alive afterthe treatment of the primary infection and the bacteria is capable to multiplythemselves. Reactivation of the bacteria in the body will lead to a condition whichis called as reinfection. Reinfection is the condition in which the person willhas a repeat infection after the primary infection. The reasons why a personwill be getting reinfection is due to the weakening of the immune system by HIVinfection. Theimmune response of the patient results in lesions that is characteristicallylocalized and this is often accompanied with the excessive tissue destructionand cavitation.
The transmission of the disease is more common and easy if theperson who is having the post-primary tuberculosis. Usually, the post-primarytuberculosis will affect the lungs but the others part of the body will alsobeen affected. The manifestation of the lung will be more obvious in this case.There are some of the characteristics of the post-primary tuberculosis. Therewill be positive sputum smear and also lung destruction with cavitation. It isusually no intrathoracic lymphadenopathy. Theeffects of the post-primary tuberculosis has divided into two categories whichare pulmonary tuberculosis and extra-pulmonary tuberculosis.
Pulmonarytuberculosis has the following symptoms which are lung cavities, upper lobeinfiltrates, fibrosis, endobronchial and also progressive pneumonia. Inextra-pulmonary tuberculosis, there are some symptoms which are common andthere are also some of the manifestations are less common. Pleural effusion,pericarditis, lymphadenopathy and also meningitis are the common symptoms ofpost-primary infection. Gastrointestinal such as ileocaecal and also peritonealwill 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 andorchitis which are the symptoms that are related to the male genital tract arealso the outcome of the extra-pulmonary tuberculosis. Extra-pulmonarytuberculosis will also affect the female genital tract like endometrium andtubo-ovarian.
There will be also skin infection which include lupus vulgaris,tuberculids and military. Strategiesfor the management of tuberculosis Thereare many ways to manage tuberculosis include drug regimens and also vaccinedevelopment. The purposes of managing tuberculosis are that we can prevent theexacerbations of the disease and also we can totally remove the pathogens thatpresent in our body. The management of tuberculosis will also prevent thetransmission of the disease to other people and to prevent the recurrentinfection of the patient in the future.
Tuberculosis is a well-known disease inwhich it will affect the population in the world. The treatment for thisdisease in term of drug already exists for more than 50 years old. Yet, why theprevalence of the tuberculosis is not getting less instead it increases in ahigh rate? This is because the management of the disease is not proper althoughthere are many drug regimens to treat the disease.
In order to has a properanti-tuberculosis drug treatment, short-course chemotherapy (SCC) has to beapplied to the patients. In order to make sure that SCC is being carried out ina proper manner, well managed TB control programme (NTP) has to be done. In thestandardized TB treatment, there are many treatment regimens available to treattuberculosis. Each country will apply different standard regimens to fulfil thepurposes of anti-TB drug treatment.
The regimen for tuberculosis is the mostcost- effective of all the interventions and it is affordable for all walks oflife. There are certain drugs which are classified into first-line anti- TBdrugs and they have different modes of action, potency and dose applied. The drugsinclude isoniazid (H), rifampicin (R), pyrazinamide (Z), thioacetazone (T),streptomycin (S), and also ethambutol (E).
These drugs are divided into twomain types which are bactericidal and bacteriostatic. Bactericidal drugs willkill the bacteria while bacteriostatic will only slow down the production andgrowth of the bacteria. Amongthese 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 stopfor a time, then continues back. Thioacetazone cannot be used for intermittent purposeand it has many side effects as it will cause toxicity to the people whoconsume it and it will also cause severe skin reactions. Besides, it also haslow property of bacteriocidal action. Thus, it is now seldom be used. It is nowbeen substituted with other drug like ethambutol.
Theabove drugs that mention above act on different groups of bacilli. Tuberculosisbacilli in a tuberculosis patient are divided into different groups such asbacilli that are metabolically active, continuously growing in the host body.There are also bacilli that stay inside cells such as macrophages.
Moreover, thereis semidormant bacilli which will undergo occasional spurts of metabolic activityand also dormant bacilli. Dormant bacilli will fade away and die away. Among thesebacilli, semidormant bacilli is the most difficult bacilli to remove. That’swhy the anti- tuberculosis treatment needs longer period to act againstdifferent groups of bacilli. Isoniazid, rifampicin, pyrazinamide and streptomycinare the drugs that classified as bactericidal drugs. Among these drugs,isoniazid is the best to kill the metabolically active bacilli. It almost cankill 90% of continuously growing bacilli.
Nevertheless, isoniazid cannot killsemidormant bacilli but rifampicin can. The bacilli that live inside the cellslike macrophages are killed by pyrazinamide. This bacilli are killed in theacid condition inside the cells.
Thetable below shows how the drugs are being consumed in order to help toeliminate 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 bacteriais the toughest bacilli to be removed through our body. Thus, rifampicin whichis able to remove this bacteria is considered to be the most effective drugs totreat tuberculosis drugs.
There are some of the bacilli that are considered tobe drug-sensitive bacilli in which they are resistant to certain drugs and theyare very difficult to be removed. This is why sometimes we need the combinationof the drugs in order to provide a wide range of bactericidal andbacteriostatic action. Isoniazid and rifampicin are the best combination in orderto prevent the bacilli which will easily develop the resistance property tosome drugs. Stremptomycin and ethambutol are less effective if compared tocombination of isoniazid and rifampicin.