Volume. 35, No. 2 july. 2011 - The Chest and Heart Association of ...

Chest & Heart Journal Vol. 35, No.-2, July 2011IntroductionIn many areas of the world tuberculosis remainsthe most common causes of pleural effusion withgranulomatous pleuritis in the absence ofdemonstrable pulmonary diseases 1 . About 95%cases of granulomatous pleuritis are due toinfection by M. tuberculosis 2 . Tuberculosis is anancient human disease. Today pulmonarytuberculosis has become the most importantcommunicable disease in the world which isresponsible for more morbidity and mortality thanany other bacterial infections. Around one-thirdof the world’s population has latent tuberculosisand that between 2002 and 2020, an estimate of1000 million people will become newly infected,150 million people will contact disease and 36million will die 3 . Bangladesh ranks 6 th thth in theworld of tuberculosis disease burden with anestimated over 3,00,000 new cases each year ofwhom 70,000 die per year 4 .There is no prevalence study on granulomatouspleuritis in Bangladesh till now. A study in a smallscale was done in 2002, where prevalence of EPTBwas only 4.8% 5 . Incidence and prevalence ofpulmonary TB in Bangladesh are 225/100000population per year and 391/100000 population peryear respectively 6 .Though pulmonary TB is the most commonpresentation of M. tuberculosis infection, extrapulmonary TB also constitute a frequent problem,particularly due to advancing immunosuppressionin the era of HIV infection 7,8 . Tuberculous pleuraleffusion (TPE) which usually causes grnulomatouspleuritis is the second most common form of extrapulmonary tuberculosis. Granulomatous pleuritisresults from a hypersensitivity reaction totuberculin protein 9 . The incidence ofgranulomatous pleuritis is linked to the localprevalence of TB in general. In India EPTBconstitutes about 15-20% of all cases of tuberculosisin immunocompitent adult, among themtuberculous pleural effusion occurs in 20% cases7 . In many areas of the world tuberculosis remainsthe most common causes of pleural effusion withgranulomatous pleuritis in the absence ofdemonstrable pulmonary diseases 1 . It has been amajor health problem in the developing countrylike Bangladesh.A wide range of diseases may be the cause of anaccumulation of fluid in the pleural space butgranulomatous pleuritis is almost always causedby infection with M. tuberculosis leading to pleuraleffusion 10 . Pleural effusion is a major diagnosticproblem, time may be wasted before an accuratediagnosis is made in patients with pleural effusion,as the pleura is an inner cavity with no directaccess, adding some difficulty to the diagnosis 11 .Pleural effusion can occur as a complication ofmany different diseases. It is a common clinicalproblem and it has been estimated that there are>800,000 cases/year in the USA. The diagnosis ofgranulomatous pleuritis remains a controversialissue in terms of cost to both patients and thehealthcare system. Conventional methods are notalways capable of establishing the cause of pleuraleffusion, and alternative tests permitting rapid andaccurate diagnosis are greatly needed. Malignantdisease involving the pleura and parapneumoniceffusion are the leading causes of exudative pleuraleffusions 12 . Fluid collection within the pleuralcavity can be assessed with clinical and radiologicalmeans. When pleural effusion is detected, thecharacteristics of the fluid (exudate or transudate)must be revealed using thoracocentesis 13 .The determination of the aetiology of the pleuraleffusion with granulomatous pleuritis was basedon the clinical presentation, appropriate diagnostictest results and response to treatment of eachpatient 12 . Granulomatous pleuritis is thought tobe the result of a delayed hypersensitivity reactionin response to the presence of mycobacterialantigens in the pleural tissue. This immunologicreaction causes the stimulation and differentiationof lymphocyte which release lymphokines whichin turn activate macrophages for an enhancedbactericidal effect 14 . Despite the introduction andpopularity of the new methods of Mycobacteriumtuberculosis detection and identification, thediagnosis of some cases of tuberculosis, continuesto pose considerable difficulty. The definitivediagnosis of granulomatous pleuritis is difficultbecause of the low sensitivity and specificity of noninvasive traditional diagnostic tools, the result ofpleural fluid staining for acid fast bacilli (AFB) isvirtually negative and pleural fluid culture for AFBis positive in only