23 March 2018 11:35 am Views - 3965
In an attempt to put World Tuberculosis Day under the spotlight, today’s Health Capsule will shed more light on TB; an epidemic deemed to be a global health challenge. In conversation with Health Capsule, District TB Control Officer of the District Chest Clinic - Gampaha attached to the National Programme for Tuberculosis Control and Chest Diseases, Dr. A.Ramachandran explicated the intricacies evolving around TB and what should be done to prevent oneself from falling prey to such an infectious disease.
A disease that spreads through the air
Explaining what the disease is, Dr. Ramachandran said that TB is an infectious disease caused by a bacteria known as MYCOBACTREIUMTUBERCULOSIS. The disease could occasionally be caused by MYCOBAETERIUM BOVIS and MYCOBACTERIUM AFRICANUM. “TB mainly affects the lungs (80% ), but it could affect any part of the body except hair and nails . The commonest sites that could be affected other than the lungs are Lymph nodes in the neck, Pleura ( covering around the Lung ), vertebral column and others” explained Dr. Ramachandran.
Elaboroating on how the disease could spread, he said that TB spreads through the air as droplet nuclei. “When a patient with TB of the lungs, mainly a person with a progressive disease coughs or laughs or talks aloud, they release the bacteria into the air as droplet nuclei. A person who inhales this air will get infected. All people who are infected don’t develop the disease. To explain it further, if 100 people are infected 10 will develop the disease. The risk of developing the disease is greatest during the first 2 years after infection. However, this also depends on the infected person’s immunity and the duration he or she remains in contact with the diseased person,” he added. Stating that TB is completely curable, Dr. Ramachandran added that the outcome is optimal when the disease is detected early and treated with quality assured drugs for the recommended duration of treatment.
When a person does not take treatment properly, his or her disease will not be cured
Causative factors and risk groups
According to the doctor, the development of the disease in an infected person is largely dependent on his immunity. If a diseased person (index patient) has extensive progressive disease ( large number of bacilli in the Lungs ) and has prolonged contact with his people nearby, then the infected people have a greater chance of contracting the disease. Moreover, in the event, the infected person lives in a crowded and dark environment with less ventilation, then the chances of developing the disease is higher. “Similarly if the infected person is malnourished or suffers from diseases like diabetes or cancer, such people are more prone to develop TB. HIV infected people when in close contact with a TB patient has a greater chance of developing TB. People who smoke , consume alcohol or substance abusers have a greater chance of developing TB.
People living in overcrowded settings such as slums, camps, homes, rehab centres and those who are engaged in certain professions such miners, building workers are identified as vulnerable groups prone to contract or develop the disease. Also, smokers, alcoholics, substance abusers and HIV infected people including patients with certain diseases such as diabetes or cancer can be listed as vulnerable groups for TB” he said.
Red flag signs
In addition patients could have,
Adding that patients with Extra Pulmonary TB ( excluding Lung ) would not have cough or chest related symptoms, but will present with other symptoms, Dr. Ramachandran further explained that all patients who take their prescribed treatment properly will have little chance of contracting the disease again. Therefore, TB is totally curable.
Diagnosis and treatment
Elucidating that TB is mainly diagnosed by obtaining a patient”s sputum, he said that the sputum sample will be smeared and stained with Zeil Nielson stain and examined under a microscope. This is also known as the‘ Sputum Smear Examination’.
“In addition to the Sputum Smear Examination, Chest X rays are commonly used in diagnosing the disease. TB culture is known as the gold standard in the diagnosis of TB . Lowenstein Jennson Medium Culture is the traditional culture method, but it would take 2-3 months to determine the diagnosis in some patients.
Nowadays a culture method known as Rapid Liquid Culture ( Bactec ) is available which can give a diagnosis for TB in 2 weeks.
“In the last 2 years, a molecular diagnostic test method known as Xpert MTB/ Rif ( commercially known as Gene Xpert) which can give a diagnosis in 2-4 hours after the sample is collected put into the machine. It is a rapid diagnostic method. The National Programme for Tuberculosis Control and Chest Diseases (NPTCCD ) is making every effort to make this test widely available in the country. Already 11 Gene Xpert machines are in use throughout the country. Choice of a culture method is dependent on the patient’s clinical situation. Culture tests are requested when there is a strong clinical suspicion of TB and the sputum smear examination has failed to give the diagnosis. In addition a skin injection test known as Mantoux test is used in the diagnosis of TB,” he explained.
He took this opportunity to make known to all that obtaining a correct sample of sputum (not saliva ) is the key in the diagnosis of TB. Patients should be given the idea that it has to come from the chest. The patient is advised to breathe in and out 2- 3 times, cough well and bring out the sputum . It should be done in a well ventilated open area with sunlight falling over the area. TB patients could be broadly classified into New patients (who get TB for the first time ) and Previously treated patients. Previously treated patients are those who develop TB again, who do not progress on their treatment as expected ( failure ) or those who interrupt their treatment (Defaulters or Lost to follow up ). Most of them are treated with 4 types of oral antibiotics namely Isoniazid, Rifampicin, Pyrazinamide and Ethambutol. Some of the previously treated patients may require Streptomycin in addition as an injection. He said that many new patients are treated for 6 months. However, previously treated patients will be treated for 8 months. In some special cases of TB like TB meningitis and Spinal TB, patients are treated for a period of one year.
“When a patient does not take his treatment properly, his disease will not be cured. His lungs will be damaged badly and he will have difficulty in breathing. He may die of the disease and can easily spread the disease to those who are very close to him like his own family members. Further, a patient who doesn’t take his treatment regularly will develop drug resistance also known as ‘MULTI DRUG RESISTANT TB’ (MDR-TB). This is a very difficult form of TB to treat. The people who are closer to these patients will also develop the same form of TB that is difficult to treat. For the past 10 years TB has shown a static pattern in Sri Lanka. 8,500- 9,000 cases of TB are diagnosed each year,” Dr. Ramachandran said. MDR TB for the moment remains as a less of a threat with 10- 12 cases being diagnosed each year .
“TB is a totally curable disease. The best way to protect yourself from TB is to help identify people with symptoms of TB.The diagnosed patients should be helped in taking their treatment properly. TB patients after taking their treatment for about a month are almost non infectious. They cannot pass the disease to another person. We should not shun TB patients. The stigma that is associated with TB patients should be removed. This is done by making ‘our’ TB patients feel wanted and by treating them as fellow human beings, with compassion. This way we could protect them and ourselves from the risk of TB,” he concluded.