Best Tuberculosis (TB) Treatment Hospital in Hyderabad, India

Tuberculosis (TB), caused by Mycobacterium tuberculosis, is a curable and preventable disease. However, the disease is very challenging to diagnose and treat. The World Health Organization (WHO) recommends a rapid molecular diagnostic test as the initial diagnostic test in individuals presenting signs and symptoms of tuberculosis. These rapid diagnostic tests include Xpert MTB/RIF (Xpert Mycobacterium tuberculosis/rifampicin) Ultra and Truenat assays. They have high diagnostic accuracy and will help in the early detection of tuberculosis and drug-resistant tuberculosis.

Mantoux test or tuberculin skin test (TST), interferon-gamma release assay (IGRA), or newer 

Tuberculosis antigen-based skin test (TBST) can be used to identify people with TB infection.

The Approach of Infectious Disease Specialists towards the patient

The pulmonary tuberculosis diagnosis depends on whether the patient is being tested for latent, active pulmonary, or extrapulmonary TB disease. Diagnosis is established by a combination of radiology, microbiology, molecular methods, biomarkers, and the immunologic response to provocative testing. The sensitivity of diagnostic tests varies depending on factors such as pretest probability, immunological status, patient’s age, test timing, adherence to test procedures, and the ability to explain test results in the context of the patient's risk factors. The general physician or pulmonologist may inquire about the presenting symptoms and gather the complete medical history of the patient, including family history, as an initial approach in diagnosing TB.

The pulmonologist may consider the following before diagnosing TB: 

Initial evaluation

• Medical history: Doctors may inquire about the patient’s general medical history. The physician may inquire if the patient has any symptoms of TB disease and if so, for how long, if they are exposed to or is in a close contact with a TB patient, if the patient has any risk factors to develop TB infection and if there are any underlying conditions especially Human Immunodeficiency Virus (HIV), immunocompromising conditions or diabetes that can increase the risk of progression of TB infection to TB disease. 

• Physical examination: It usually does not confirm or rule out TB, but it can provide information regarding the overall health of the patient. During a physical examination, the physician will examine the lungs and look for swelling in lymph nodes in the neck. Redness and swelling or inflammation over the infected lymph nodes of scrofula may be observed during a physical examination and can be a sign of extrapulmonary TB disease.
  

✅Diagnostic Tests for Tuberculosis

Based on the above information, the pulmonologists may recommend the following tests: 

• Testing for TB infection
• Mantoux test: Mantoux tuberculin skin test, also called Tuberculosis skin test, is used to determine if a person is infected with TB bacteria (Mycobacterium tuberculosis). In this test, a standardized solution made with purified protein derivative (PPD), which is derived from tuberculin, is injected under the skin (between layers of skin on the forearm). When a person has been infected with TB bacteria, purified protein derivative produces a T-cell mediated delayed-type hypersensitivity reaction (firm swelling on the forearm).

• Interferon gamma release assay (IGRA): It is a blood test to determine if the individual is infected with the mycobacterium tuberculosis, which is the causative agent of TB. This test works by measuring the body’s immune response to the TB bacteria. The patient’s blood samples are mixed with peptides that simulate antigens derived from TB bacteria and with controls. White blood cells respond to the simulated TB antigens and release interferon-gamma (IFN-γ). The test results of interferon gamma levels are compared with the values of controls. 

• Molecular testing 
• Xpert MTB/RIF assay: This is a nuclear acid amplification test that uses a cartridge based on the GeneXpert Instrument System. The basis of this assay is PCR (polymerase chain reaction); it can be used to detect DNA sequences specific to the MTB in sputum samples. A single Xpert MTB/RIF test can detect about 99% of smear-positive patients and more than 80% of smear-negative patients directly from sputum. The World Health Organization in the year 2014 stated that the Xpert MTB/RIF assay can be used as the initial diagnostic test in all subjects suspected of having pulmonary TB. 

• Imaging: Imaging studies are considered in the context of the stage of tuberculosis. Chest x-ray remains the initial procedure employed for screening and diagnosis. Computed tomography (CT scan), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT) are considered when necessary to define anatomic involvement with active tuberculosis.

• Chest X-ray: In patients with primary tuberculosis, X-ray findings show the resolution of parenchymal lesions. 

• Chest computed tomography (CT) scan: Images from CT scans generally provide improved sensitivity compared to x-rays for diagnosing TB. 

• Positron emission tomography-computed tomography (PET CT): These imaging techniques are helpful in assessing response to the therapy. 

• Other tests:
• Acid fast bacilli smear microscopy: This smear technique is the conventional and most commonly applied approach in the diagnosis of tuberculosis. The smear sensitivity ranges from 34% to 80%, which is limited by the paucibacillary nature of tuberculosis and the inability of some patients to produce an adequate deep expectorated sputum sample. 

• Microbial Culture: Sensitivity in culture testing ranges from 80% to 93%, and specificity is approximately 93%. Growth is visible in 2 weeks in broth media, whereas in solid media, the growth can take up to 8 weeks. Tuberculosis grown in broth media can undergo rapid drug susceptibility testing (DST) and identification by deoxyribonucleic acid probe methods.

• Biopsy: This technique is important for diagnosing TB infections in organs other than the lungs, such as lymph nodes, bones, and soft tissues. Samples of biopsy are examined for identifying histological features of TB, such as granulomas. This presence of granulomas can suggest TB, but a culture test is required for a definitive diagnosis.

✅Stages of Tuberculosis

From initial exposure to active disease, TB can progress through various stages. The following are the different stages of tuberculosis:

• Exposure: In this stage, an individual gets exposed or comes in contact with a tuberculosis patient. At this stage, the exposed individual will have a negative skin test, a normal chest X-ray, and will show no signs and symptoms of TB.

• Latent TB infection: The exposed individual will have the bacteria in the body, but no symptoms will appear at this stage. The individual will have a positive skin test and a normal X-ray. 

• TB Disease: At this stage, the individual will show signs and symptoms of active infection. The individual will show a positive skin test and an abnormal chest X-ray.

The differential diagnosis of tuberculosis occurs as a result of manifestations over prolonged periods. The following are included in the differential diagnosis of pulmonary tuberculosis: 

• Fever of unknown origin: It is defined as a body temperature greater than 38.3 Celsius which lasts for more than 3 weeks with no cause. 

• Pulmonary infections: It generally refers to an infection of the lungs and it results in inflammation. Symptoms include chest congestion, difficulty breathing, coughing, wheezing, and fever. It is caused by the following 
• Parasitic 
• Fungal 
• Viral
• Bacterial 
• Nontuberculous mycobacteria 

• Autoimmune diseases: It is a condition where the immune system attacks its own healthy tissues and cells mistakenly. Psoriatic disease, rheumatoid arthritis, and celiac disease are some of the examples of autoimmune disease. 

• Sarcoidosis: It is a condition which results in the formation of lumps or nodules in lungs, lymph nodes, skin, eyes, and various other parts of the body. It is a multisystem disorder of unknown etiology. 

• Neoplasia: It is the process of abnormal and uncontrolled cell growth that can lead to the formation of a neoplasm known as a tumor. It includes a series of genetic mutations that allow cells to bypass normal regulatory mechanisms governing growth and division.
• Renal
• Peritoneal 
• Gastrointestinal 
• Hematologic 
• Metastatic tumors
• Lungs