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All about Tuberculosis in Nepal with Prevention, Diagnosis, Medicines, Symptoms & Causes: – Tuberculosis (TB) is an infectious disease normally caused by the Mycobacterium tuberculosis (MTB) bacterium. Tuberculosis usually affects the lungs but can affect other parts of the body as well. Most infections have no symptoms.

In this case, one speaks of latent tuberculosis. About 10% of latent infections develop into an active disease that, if left untreated, kills about half of those affected. The classic symptoms of active TB are a chronic cough with phlegm that includes blood, fever, night sweats and weight loss.

In the past, it was called “consumption” because of weight loss. Infection of other organs can cause a variety of symptoms.

Tuberculosis is transmitted through the air when people with active tuberculosis cough, spit, talk or sneeze in the lungs. Active infections are most common in people living with HIV / AIDS and smokers. Diagnosis of active TB is based on chest X-ray, microscopic examination and culture of body fluids. The diagnosis of latent TB is based on the Tuberculin Skin Test (TST) or the blood test.

The prevention of tuberculosis includes the detection of high-risk patients, the early detection and treatment of cases as well as the vaccination with the Bacillus Calmette-Guerin (BCG) vaccine.

Tuberculosis TB in Nepali

Tuberculosis (TB) in Nepal

At-risk persons include domestic, professional and social contacts of people with active tuberculosis. Treatment requires the use of multiple antibiotics over a long period of time. Antibiotic resistance is a growing problem with rising rates of drug-resistant multiple tuberculosis (MDR-TB) and largely drug-resistant tuberculosis (TB-XDR).

As of 2018, it is estimated that one-quarter of the world’s population is infected with TB. Every year about 1% of the population is infected. In 2017, there were more than one million cases of active tuberculosis, in which millions of people died.

This makes it the most common cause of death from an infectious disease. In developing countries, India, China, Indonesia, Pakistan and the Philippines, there were not a few deaths. Since then, the number of new cases has decreased every year.

Nearly a few people in many Asian and African countries test positive, while only a few people in the United States test positive for tuberculin.

Tuberculosis can infect any part of the body, but more often occurs in the lungs (so-called pulmonary tuberculosis). Extrapulmonary tuberculosis occurs when tuberculosis develops outside the lungs, although extrapulmonary tuberculosis may coexist with pulmonary tuberculosis.

Common signs and symptoms include fever, chills, night sweats, loss of appetite, weight loss and fatigue. It can also come to a significant knocking of the nails.

Pulmonary During TB

When a tuberculosis infection becomes active, it most often affects the lungs (in some cases). Symptoms may include chest pain and persistent cough that produces sputum. Few people may have no symptoms (i.e. they remain “asymptomatic”).

Occasionally, people may cough up small amounts of blood and, in very rare cases, may erode the infection in the pulmonary artery or in a Rasmussen’s aneurysm. which leads to massive bleeding.

Tuberculosis can become a chronic disease and lead to extensive scarring in the upper lung lobes. The upper lobes are more frequently affected by tuberculosis than the lower lobes. The reason for this difference is not clear. This may be due to better airflow or poor lymphatic drainage into the upper lungs.

In 15-20% of active cases, the infection spreads outside the lungs and causes other types of tuberculosis. These are collectively referred to as “extrapulmonary tuberculosis”. Extrapulmonary TB is most prevalent in immunocompromised and young children.

This is more common in people with HIV. Notable sites of extrapulmonary infection include the pleura (in tuberculous pleurisy), the central nervous system (in tuberculous meningitis), the lymph system (in the scrotum), the urogenital system (in urogenital tuberculosis) and the bones and joints (in Pott’s spine) others.

One potentially more severe and widespread form of tuberculosis is referred to as “disseminated tuberculosis,” also known as miliary tuberculosis. Miliary tuberculosis currently represents a few extrapulmonary cases.

Causes of Tuberculosis

Mycobacteria

The main cause of tuberculosis is Mycobacterium tuberculosis (MTB), a small, aerobic and non-motile bacillus. The high lipid content of this pathogen explains many of its unique clinical features.

It is split every hour, which is an extremely slow rate compared to other bacteria that usually split in less than an hour. Mycobacteria have an outer membrane lipid bilayer.

When Gram staining is performed, MTB stains very slightly “gram-positive” or does not retain the stain due to the high lipid and mycolic acid content of its cell wall. MTB tolerates weak disinfectants and survives dry for weeks. In nature, the bacteria can grow only in the cells of a host organism, while M. tuberculosis can be grown in the laboratory.

Using histological staining on slime sputum samples (also called “sputum”), scientists can identify MTB under a microscope. Since MTB still has some stains after treatment with an acid solution, it is classified as an acid-resistant bacillus.

The most common acidic staining techniques are the Ziehl-Neelsen stain and the Kinyoun stain, which stain the acid-resistant bacilli of a bright red spot that stands out against a blue background. Auramine-rhodamine staining and fluorescence microscopy are also used.

The M. tuberculosis complex (MTBC) includes four other mycobacteria that cause tuberculosis: M. bovis, M. africanum, M. canetti, and M. microti. M. africanum is not widespread but is an important cause of tuberculosis in some parts of Africa.

M. bovis was once a common cause of tuberculosis, but the introduction of pasteurized milk has almost completely eliminated this problem for public health in industrialized countries. M. canetti is rare and seems to be confined to the Horn of Africa, although some cases have occurred in African emigrants. M. microti is also rare and almost only occurs in immunodeficient individuals, although its prevalence can be significantly underestimated.

Other known pathogenic mycobacteria include M. leprae, M. avium and M. kansasii. The last two species are classified as “non-tuberculous mycobacteria” (NTM). NTM does not cause TB or leprosy, but it causes lung diseases that are similar to TB.

Risk factors of Tuberculosis in Nepal

Several factors make people more susceptible to TB infections. The world’s most important risk factor is HIV; Only a few people with TB are infected with the virus. This is a particular problem in sub-Saharan Africa, where HIV rates are high.

Of the people without HIV who are infected with tuberculosis, some develop an active illness during their lifetime. In contrast, only a few of those co-infected with HIV develop an active disease.

Tuberculosis is closely linked to overcrowding and malnutrition, making it one of the major diseases of poverty. Risk groups therefore include: persons injecting illicit drugs, residents and employees of places where vulnerable people gather (eg prisons and homeless shelters), medically disadvantaged communities and poor resources, high-risk ethnic minorities, children in close quarters Contact with high-risk persons.

Patients of the risk category and service providers who care for these patients. Chronic lung disease is another significant risk factor. Silicosis increases the risk of folding. Who smokes cigarettes, compared to non-smokers an almost twice as high TB ​​risk? Other disease states can also increase the risk of tuberculosis. These include alcoholism and diabetes mellitus (tripling).

Certain medications such as corticosteroids and infliximab (a monoclonal anti-αTNF antibody) are other important risk factors, especially in industrialized countries. Genetic susceptibility also exists, so the general meaning remains undetermined.

Mechanism to affected Tuberculosis by Virus

Transmission

When people with active lung TB cough, sneeze, talk, sing or spit, they emit infectious aerosol droplets with a diameter of 0.5 to 0.6 μm. A single sneeze can deliver up to 40,000 drops. Any of these drops can transmit the disease as the contagious tuberculosis dose is very low (inhaling fewer bacteria can cause infection).

People with prolonged, frequent or close contact with people with tuberculosis have a particularly high risk of infection with an estimated infection rate. A person with active but untreated tuberculosis can infect 10 to 15 (or more) other people per year.

Transmission should only be done by persons with active TB. It is not believed that people with latent infection are contagious, the level of immunity in the patient infected person and others. The person-to-person spreading cascade can be overcome by separating those with active (“overt”) TB and dividing them into TB medication regimens.

After about two weeks of effective treatment, subjects with non-resistant active infections are generally not contagious to others. If someone becomes infected, it usually takes three to four weeks for the newly infected person to be infectious enough to spread the disease to others.

Pathogenesis

Approximately some of those infected with M. tuberculosis have asymptomatic latent TB infections (sometimes referred to as LTBI) with the likelihood that a latent infection will progress to an active and overt tuberculous disease.

In people with HIV, the risk of developing active TB increases to almost 10% per year. If no effective treatment is given, the mortality rate for active TB cases is up to 66%.

TB infection begins when mycobacteria reach the alveolar alveoli of the lungs, where they invade and multiply into the endosomes of the alveolar macrophages. Macrophages identify the bacteria as foreign and try to eliminate it by phagocytosis.

During this process, the bacterium is enveloped by the macrophage and temporarily stored in a membrane-bound vesicle called the phagosome. The phagosome is then combined with a lysosome to create a phagolysosome. In the phagolysosome, the cell tries to use reactive oxygen and acid species to kill the bacteria.

However, M. tuberculosis has a thick and waxy capsule of mycolic acid that protects it from these toxic substances. M. tuberculosis can multiply in the macrophage and eventually kills the immune cell.

Tuberculosis of the lungs may also be due to infection of the bloodstream. This is called Simon focus and is usually located in the upper part of the lungs. This hematogenous transmission can also spread the infection to more distant sites such as peripheral lymph nodes, kidneys, brain and bone.

The disease can affect all parts of the body, although it rarely affects the heart, skeletal muscle, pancreas, or thyroid for unknown reasons. Macrophages, T lymphocytes, B lymphocytes and fibroblasts are added to form granulomas, with lymphocytes surrounding infected macrophages.

When other macrophages attack the infected macrophages, they merge in the alveolar light into a multinucleated giant cell. Granulomas can prevent the spread of mycobacteria and provide a local environment for the interaction of cells of the immune system.

However, recent evidence suggests that the bacteria use granulomas to prevent destruction by the host’s immune system. Macrophages and dendritic cells in granulomas cannot present lymphocytes with antigen. This suppresses the immune response.

The bacteria in the granuloma can become inactive, resulting in a latent infection. Another feature of granulomas is the development of abnormal cell death (necrosis) in the center of the granuloma Granulomas. At first glance, it has the texture of a soft white cheese and is called caseous necrosis.

When tuberculosis bacteria enter the bloodstream from an area of ​​damaged tissue, they can spread throughout the body and form many foci of infection, all of which appear as small white tubers in the tissue. This severe form of tuberculosis, which is more common in young children and those infected with HIV, is called military tuberculosis.

People with this common tuberculosis also have a high mortality rate (some) when they receive treatment. In many people, the infection increases and decreases. Tissue destruction and necrosis are often in balance with healing and fibrosis.

The affected tissue is replaced by scars and cavities filled with necrotic material. During an active disease, some of these cavities adhere to the air ducts (bronchi) and this material may cough. It contains live bacteria and, therefore, can spread the infection.

Treatment with appropriate antibiotics kills the bacteria and allows healing. After healing, the affected areas are eventually replaced by scar tissue.

Diagnosis of Tuberculosis in Nepal

Active tuberculosis

The diagnosis of active tuberculosis, which is based only on signs and symptoms, is difficult, as is the diagnosis of the disease in immunocompromised patients. However, a diagnosis of TB should be considered in patients with evidence of lung disease or constitutional symptoms that last more than two weeks.

A chest x-ray and multiple rejection cultures for acid-fast bacilli are usually part of the initial evaluation. Interferon gamma release tests and tuberculin skin tests are of little use in developing countries.

Interferon gamma release (IGRA) studies have similar limitations in people with HIV. A definitive diagnosis of tuberculosis is made by identifying M. tuberculosis in a clinical sample (eg, sputum, pus or tissue biopsy). However, the difficult culture process for this slow-growing organism may take two to six weeks for blood or sputum to be generated.

Therefore, treatment is often started before the confirmation of the cultures. Nucleic acid amplification assays and adenosine deaminase assays can allow a rapid diagnosis of TB. However, these tests are not routinely recommended because they rarely change the way a person is treated.

Latent tuberculosis

The Mantoux tuberculin skin test is often used to evaluate people at high risk for tuberculosis. Those who have previously been vaccinated with the Bacille Calmette-Guerin vaccine may have a false positive result. The test can be false negative in people with sarcoidosis, Hodgkin lymphoma, malnutrition and especially active tuberculosis.

Interferon gamma release tests in a blood sample are recommended for those who are positive in the Mantoux test. These are not affected by vaccines or most of the mycobacteria in the environment, resulting in less false positives.

However, they are affected by M. szulgai, M. marinum and M. kansasii. The US preventive services work team UU. (USPSTF) has recommended that people at high risk for latent tuberculosis be treated with tuberculin skin tests or with interferon gamma release tests.

While some have recommended testing health workers, the benefits are bad at this time. The Centers for Disease Control and Control (CDC) did not recommend in 2019 annual health care professionals who were not aware of any exposure.

What treatment do I need for latent TB?

A course of antibiotic medicine will treat latent TB. You may be given rifampicin and isoniazid (possibly in a tablet called Rifinah) for three months or just isoniazid for six months. Your TB doctor or nurse will guide you through treatment and answer all your questions.

Is the treatment of latent TB safe?

As with all medications, side effects can occur. Some are mild, while others can be more serious. Depending on the treatment you receive, the following side effects may occur:

  1. Orange spots on tears, saliva, urine and other body fluids: This is not harmful, but can stain contact lenses
  2. Pseudo-flu symptoms
  3. Menstrual disorders
  4. Reduced effectiveness of hormonal contraceptives
  5. Tingling or numbness
  6. Rashes and itching
  7. Illness or diarrhea
  8. Isoniazid
  9. Tingling or numbness
  10. Rashes and itching
  11. Illness or diarrhea

I do not feel bad, why should I take the treatment for latent TB? Very rarely, the drug can cause jaundice that causes yellowing of the skin or eyes. Isoniazid and Rifinah can affect your vision, but this is rare.

However, if you notice any of these side effects, stop taking your TB tablets and talk to a doctor or nurse immediately. Prevention is better than cure. Approximately in people with latent tuberculosis active tuberculosis develops.

And there is no way to know if you will be one of them. It is possible that many years after inhaling the TB bacteria, you may develop active TB. Treatment is the only way to remove tuberculosis bacteria from your body.

The treatment of latent TB is often shorter than the treatment of active TB and requires less medication. These are all good reasons to treat latent TB bacteria while they are healthy and before they have a chance to wake up.

How do I take medication for latent TB?

It is important that you take your medications on a regular basis and go through the entire course to ensure that all tuberculosis bacteria are eliminated from your body. Try to take your tuberculosis medication at least one hour before meals or two hours later. You can eat whatever you want, but you should abstain from alcohol, concerned about the treatment of latent tuberculosis.

You will be assisted by a doctor or a TB nurse throughout your treatment. They will accompany you during the treatment and answer all your questions. Once you have all the information you need, you can decide if the treatment is the best option for you.

If you have started treatment but are still worried, remember that your doctor and nurse are there for you. Be sure to meet all your clinical appointments and tell your doctor or nurse about possible side effects. If you have problems taking our medications, they can help you.

If I finish my treatment, will I be free of TB forever?

If you complete your treatment as prescribed, your risk of developing active TB is much lower. However, you may be able to breathe again the tuberculosis bacteria in the future. The likelihood of this is low for most people, but it is useful to know the most common symptoms of active TB so you can see your family doctor if you have one:

  1. A cough that lasts three weeks or more
  2. fever (high temperature)
  3. 3rd night is sweating
  4. Weight loss
  5. no appetite
  6. fatigue.

Prevention for Tuberculosis

Efforts to prevent and control tuberculosis depend mainly on the vaccination of infants and the detection and proper treatment of active cases. The World Health Organization (WHO) has made some achievements with better treatment plans and a small decrease in case numbers.

Vaccinations

The only vaccine available from 2011 is Bacillus Calmette-Guerin (BCG). In children, the risk of infection decreases by 20% and the risk of active disease by almost 60%. With more than 90% of all vaccinated children, it is the world’s most widely used vaccine.

The induced immunity decreases after about ten years. Since tuberculosis is uncommon in most parts of Canada, the United Kingdom and the United States, BCG is only given to high-risk groups.

Part of the arguments against the use of the vaccine is that it makes the tuberculin skin test falsely positive, which reduces the usefulness of the test as a screening tool. Several vaccines are under development.

Public health Of Nepal

The World Health Organization (WHO) stated that TB would be a “global health emergency” in 2019. The Stop TB Alliance developed a global plan to fight tuberculosis that aimed to save millions of lives between their launch.

Several targets were not set, mainly due to the increase in HIV-associated tuberculosis and the occurrence of multidrug-resistant tuberculosis. A tuberculosis classification system developed by the American Thoracic Society is mainly used in public health programs.

How to manage TB?

TB treatment uses antibiotics to kill bacteria.  Latent tuberculosis is treated with isoniazid alone or with a combination of isoniazid with rifampin or rifapentine. The treatment lasts at least three months.

People with latent infections are being treated to prevent them from developing active TB disease later in life. Active TB disease is best treated with a combination of several antibiotics to reduce the risk of bacteria becoming resistant to antibiotics.  In the case of high isoniazid resistance, ethambutol may alternatively be added in the last four months.

Recurring illness/Medication resistance

When tuberculosis recurs, it is important to run tests to determine which antibiotics are sensitive before treatment is determined. If multiple drug-resistant TB (MDR-TB) is detected, treatment with at least four effective antibiotics for months is recommended.

The World Health Organization (WHO) recommends directly observed therapy, i.e. monitoring of the person taking their medication by a healthcare provider to reduce the number of people who are not taking antibiotics properly.,

The evidence supporting this practice in people who simply take their medication independently is of poor quality. There is no solid evidence that the therapy being observed improves the number of people healed or the number of people completing their medication.

The signs of moderate quality suggest that there is no difference in whether people are being observed at home or in a clinic, or by a family member or healthcare professional. Methods that remind people of the importance of treatments and appointments can lead to a small but important improvement.

Primary resistance occurs when a person becomes infected with a resistant TB strain. Drug-resistant tuberculosis is a serious public health problem in many developing countries as it takes longer to be treated and requires more expensive drugs. MDR-TB is defined as resistance to the two most effective first-line antituberculotic drugs: rifampicin and isoniazid.

Most drug-resistant tuberculosis is also resistant to three or more of the six classes of second-line drugs. Fully drug-resistant tuberculosis is resistant to all currently used drugs. It was first observed in Italy, but first reported on a large scale, and it was also found in Iran and India.

Bed aquiline is currently suitable for the treatment of multidrug-resistant tuberculosis. XDR-TB is a term sometimes used to define largely resistant TB, accounting for one in ten cases of MDR-TB. Cases of XDR tuberculosis have been reported in more than a few countries.

Prognosis of TB

The progression of TB infection to open TB disease occurs when the bacilli overcome the immune system’s defenses and start to multiply. In primary tuberculosis (about 10% of cases), this occurs shortly after the initial infection. In most cases, however, a latent infection occurs without obvious symptoms.

These latent bacilli produce active tuberculosis in 5-10% of these latent cases, often many years after infection. The risk of reactivation increases with immunosuppression, such as HIV infection. In people co-infected with M. tuberculosis and HIV, the risk of reactivation increases to a few per year.

Studies using DNA fingerprints of M. tuberculosis strains have shown that reinfection contributes significantly more to recurrent tuberculosis than previously thought. According to estimates, this could represent more than a few cases in which areas were reactivated in TB is widespread. The likelihood of dying from tuberculosis is a few.