Image 1
Frontal Chest x-ray of a young Vietnamese man presenting with weight loss and cough. Chest x-ray shows extensive bilateral perihilar, mid and upper zone air space disease. There are a combination of consolidations with differing sized cavities featuring irregular wall thickening and bronchiectasis. Bronchiectasis is abnormal widening of the bronchi or their branches. Also evident are variable-sized nodules around the cavitary foci that are spread throughout both lungs. Small foci containing Mycobacterium Tuberculosis may calcify or these foci often contain viable organisms. The nature and pattern of lung involvement is diffuse. Further imaging revealed extensive airspace consolidations and irregular thick walled cavity formation in the right and left upper lobes and cavities in both the lower lobes. Findings: Active Mycobacterium Tuberculosis with endobronchial spread.
Mycobacterium Tuberculosis
Tuberculosis (TB) is a widespread, contagious infectious disease caused by various strains of mycobacteria, usually Mycobacterium Tuberculosis.(1) Tuberculosis usually attacks the lungs but can affect other parts of the body including the brain, bones and nervous system. Tuberculosis is an air-borne infection, which means it spreads through the air by inhaling tiny droplets from the coughs or sneezes or respiratory fluids of an infected person.(2) Not everybody who is infected with Tuberculosis bacteria becomes ill, so the disease is divided into two classifications which are latent and active Tuberculosis. Tuberculosis can remain latent, that is inactive with no symptoms, except for a positive tuberculin skin test or a positive blood test. In the latent stage the disease is not infectious and cannot be transmitted. Around one in 10 (or about 5 – 10%) of people with latent infections will eventually progress to active disease often within the first two years of contact with the bacteria. Any patients who have a compromised immune system, such as those who are HIV positive, have a much higher risk of active tuberculosis. HIV infection is the number one predisposing factor for Mycobacterium tuberculosis, 10% of all HIV patients are positive for Tuberculosis which is 400 times the normal rate.(3)
Image 2
Frontal Chest X-Ray of a 43 year old white male. In 1999 the patient presented with temperature and a cough and was found to have active Tuberculosis. Patient was treated with drug therapy. In 2000 the patient was found to have middle and lower lung pathological findings on a routine follow up. Sputum was positive for Mycobacterium Tuberculosis. A combination of drug therapy was given on suspicion of a multiresistant strain of Tuberculosis. In 2002 tests were repeated and confirmed ethambutol resistance. Drug susceptibility tests were repeated over the years but in 2006 progression of infiltration on chest x-ray worsened. Image 2 (from 2006) shows prolonged inflammation with bilateral extensive infiltrations with cavities due to Multidrug-Resistant Tuberculosis.
Multidrug-resistant Tuberculosis (MDR-TB), as illustrated in the case above, is a form of Tuberculosis that does not respond to the standard drug treatment. Globally, the proportion of new cases with multidrug-resistant Tuberculosis was 3.5% in 2013.(4)
Tuberculosis remains one of the world’s deadliest infectious diseases. In 2013 around 9 million people were infected with the disease and 1.5 million people died from it (360,000 of those deaths were HIV positive).(5) On a more positive note, Tuberculosis cases are decreasing each year, but considering it is a treatable disease and most deaths are preventable the death rate remains unacceptably high according to the World Health Organization (WHO) in 2014. The rates of Tuberculosis vary around the world with a predominance in developing countries due to much higher rates of HIV infection and AIDS (Acquired Immune Deficiency Syndrome).(6) It is estimated that as many as 80% of the population in Asia and Africa test positive compared to only 5 – 10% of people in the United States. Of the 9 million people thought to be infected with Tuberculosis over half (56 %) were in South-East Asia and Western Pacific regions and a quarter were from the African region, India had 24% of total cases and China 11%.(7)
- Footnotes
1. Kumar V, Abbas AK, Fausto N, Mitchell RN (2007). Robbins Basic Pathology (8th ed.). Saunders Elsevier. pp. 516–522. ISBN 978-1-4160-2973-1.
2. Konstantinos A (2010). “Testing for tuberculosis”. Australian Prescriber 33 (1): 12–18.
3. Todar Kenneth ‘Todar’s Online Textbook of Bacteriology’ http://textbookofbacteriology.net/tuberculosis_2.html
4,5,7 World Health Organization (WHO) ‘Global Tuberculosis Report 2014′.
6. Lawn, SD; Zumla, AI (2 July 2011). “Tuberculosis”.Lancet 378 (9785): 57–72. doi:10.1016/S0140-6736(10)62173-3. PMID 21420161.
- Sources
http://www.vcuthoracicimaging.com/Imagewindow.aspx?imgname=Uploadimg\Picture10759241718750.jpg&caption=
http://www.respiratorycasereports.com/article/S1755-0017(09)00004-9/fulltext