Pulmonary Tuberculosis - Essay Example

Pulmonary tuberculosis (TB) is a contagious bacterial infection caused primarily by Mycobacterium tuberculosis attacking mainly the lungs but could spread to and damage other organs (Mayo Foundation, 2009). TB can cause inflammation, formation of tubercules and other growths within the tissue of the lungs, and may cause tissue death. In addition TB spreads through air and a person may be exposed when in contact with a TB patient who coughs, sneezes, or talks (Mayo Foundation, 2009). Most people who are exposed are asymptomatic, the body may be infected with the bacterium but the immune system often prevents manifestation of the disease and the bacterium remains in inactive state and is not contagious. This is referred to as latent TB. Active TB on the other hand is when the exposed person becomes symptomatic and the disease is contagious. Incidence or prevalence The World Health Organization or WHO reported that there is an “estimated 8.9 – 9.9 million incident cases of TB, 9.6 – 13.3 million prevalent cases of TB, 1.1 – 1.7 million death from TB among HIV-negative people and an additional 0.45 – 0.62 million TB death among HIV-positive people” (2009). There have been advances in TB treatment but it remained the deadliest of infectious diseases infecting one-third of the population especially in developing countries where 95% of new cases and 98% of deaths occur (Ducati et al, 2006). Risk factors Anyone can contact TB but certain factors may increase a person predisposition to the disease such as the following: weak immune system, close and extended contact with patients who have untreated or active TB, long term drug or alcohol abuse, poor diet, and lack of access to medical care, the risks also increase with age (Mayo Foundation, 2009). Where a person lives, works, or travels may also increase their risk, residential care facilities, refugee camps, healthcare work, and regions where TB is prevalent (e.g., Africa, Southeast Asia, India, and China) are some of the places where TB may be easily spread (WHO, 2009). Diagnosis Symptoms of TB include: coughing that lasts for more than three weeks, coughing with blood, chest pain, difficulties in breathing, weight loss for no apparent reason, chronic fatigue, fever, night sweats, chills, and appetite loss (Mayo Foundation, 2009). If TB is suspected, the doctor may require the patient to undergo a complete medical evaluation. Tests for TB infection includes the following: skin test (Mantoux test) where PPD tuberculin is injected below the skin of the inside forearm; chest X-ray or CT scan of the lungs to detect granuloma or cavities; culture tests of sputum; biopsy of the affected tissue; bronchoscopy; thoracentesis; or microscopic-observation-drug susceptibility (MODS) assay to detect bacteria presence in sputum and identify drug resistance of TB bacteria strain (Batra & Ang, n.d.). The latter tests are done when skin and blood tests are positive. Nahid et al promoted the more advanced tools for detecting tuberculosis (2006). Two commercial kits are available for detecting latent TB - the QuantiFERON-TB Gold test and the T SPOT-TB test – which “detect cellular immune response by measuring IFN-γ released by T cells after stimulation by Mycobacterium tuberculosis antigens” (Nahid et al, 2006). Another recent advance in diagnosing TB is the nuclear acid amplification (NAA) which detects genes associated with drug resistance. Nahid et al recommend these more recent diagnostic tolls because of their greater specificity, accuracy and reliability (2006). MODS trial is still the predominant testing tool in developing countries while NAA is available in developed countries (Mayo Foundation, 2009). Treatment A combination of drugs is usually used to cure the infection and fight TB bacteria (Ducati et al, 2006; Nahid et al, 2006). Laboratory tests will be necessary to determine which treatment combination works best for the patient but the most commonly used drugs include Isonizid, Rifampin, Pyrazinamide, Ethambutol, Amikacin, Ethionamide, Moxifloxacin, Para-aminosalicylic acid, and Streptomycin. It is imperative that the drugs are administered as per the health care providers’ instructions, when tuberculosis medications are not taken as instructed, the TB bacteria may become more resistant to medications, and the infection becomes more difficult to treat. There are also bacteria strains that have proven to be resistant to drugs and quick detection of resistance is necessary to overall treatment management. To test for drug resistance, molecular beacons (detection of mutations associated with drug resistance), line probe assays (DNA strip test that reverse hybridization method), and phage-based assays (amplification of phages) are used (Nahid et al, 2006). Prognosis With the proper medical attention, symptoms usually improve within 2 or 3 weeks (Batra & Ang, n.d.). The prognosis is especially better if diagnosis of pulmonary TB is early and treatment is begun right away. Complications Tuberculosis is potentially fatal, specifically if treatment is not given early. Untreated active TB in general affects the lungs and may cause lung damage; it can, however, spread and complications depend on the location of the bacteria (Batra & Ang, n.d.). When TB infects the bones, it causes severe pain, abscesses, and joint destruction. Once TB infects the brain and central nervous system, it can result to meningitis. If TB is progressive and results to huge lymphohematogenous dissemination of the bacteria, a serious complication called miliary TB occurs. Glossary of Terms Tubercules – growths or inflammations in the affected organ associated with tuberculosis. PPD tuberculin – tests for tuberculosis using purified protein derivative (PDD) as stimulating antigen. Granuloma - a mass of chronically inflamed tissue usually associated with infections. Sputum – the mucus that comes up when a person coughs. Biopsy – the removal and examination of tissue, cells, or fluids from the living body. IFN-γ – Interferon gamma; interferon (basic glycoproteins produced by cells) that regulates the immune response. Antigen - any substance foreign to the body that evokes an immune response. Abscess – a localized collection of pus surrounded by inflamed tissue. Meningitis – inflammation of the membranes that envelop the brain and spinal cord. Lymphohematogenous – transportation of the infected macrophages to the regional lymph nodes. Miliary TB – TB has spread throughout the body. References: Batra, V. and Ang, J.Y. (no date). Tuberculosis. eMedicine. Retrieved 18 April 2010, from http://emedicine.medscape.com/article/969401-overview. Ducati, R.G., Ruffino-Netto, A., Basso, L.A., Santos, D.S. (2006) The Resumption of Consumption – a Review on Tuberculosis. Memorias do Instituto Oswaldo Cruz 101: 697-714. Mayo Foundation for Medical Education and Research (28 Jan 2009). Tuberculosis. MayoClinic.com. Retrieved 18 April 2010 from http://www.mayoclinic.com/health/tuberculosis/DS00372. Nahid, P., Pai, M. and Hopewell, P. C. (2006). Advances in the Diagnosis and Treatment of Tuberculosis. Proceedings of the American Thoracic Society 3: 103-110. World Health Organization. (2009) Global Tuberculosis Control 2009: Epidemiology, Strategy, Financing. Geneva, Switzerland: WHO. Read More