INTRODUCTIONSince its discovery by Robert Koch in 1882 (CDC, 1982), tuberculosis (TB) has and is still one of the leading causes of morbidity and mortality globally. In 2022 alone 10.6 million people were infected with TB and 1.3million died. It is the second leading infectious killer after COVID-19 (World Health Organization, 2023).Tuberculous pleuritis or pleurisy (TBP) is the second most common form of extra-pulmonary tuberculosis. It affects the pleura, in both immunocompetent and immunocomprised persons (Cohen and Light, 2015) (Nanyoshi et al. , 2022) in as high as 25% of tuberculosis(TB) cases (Porcel, 2009). TBP usually presents as a unilateral pleural effusion, although about 10% of cases are bilateral (Wang et al. , 2015).Effusions in TBP have long been postulated to be due to a delayed hypersensitivity reaction to mycobacterium antigens from raptured sub pleural caseous material; however recent advances have demonstrated a likelihood of paucibacillary bacterial infection within the pleural cavity (Morné J. Vorster, 2015).In high TB endemic areas prevalence of TBP has been shown to be higher in young people (mean age 34) (Porcel, 2009) compared to elderly population(>65years) in low endemic areas (Baumann et al. , 2007). The most common symptoms for TBP are pleuritic chest pain which precedes a non-productive cough; then fevers, night sweats, weight loss and malaise (Wang et al. , 2015).The gold standard for diagnosis of TBP is the demonstration of Mycobacterium tuberculosis in the pleural biopsy specimens, pleural fluid or sputum (Gopi et al. , 2007); the challenges to this include scarcity of thoracoscopy services, paucibacillary nature of effusion and lack of sputum (since the cough is usually non-productive). However, presumptive diagnosis can also be achieved with reasonable certainty, by showing parietal pleura granuloma (through biopsy and histology) or elevated levels of pleural fluid adenosine deaminase (ADA) or interferon-γ, considering the clinical context of the patient (Trajman et al. , 2008).Since its discovery in 1978, adenosine deaminase(ADA) test on pleural fluid has become famous in diagnosis of TBP, more so in patients with exudative and lymphocytic pleural effusion in high TB endemic areas (Aggarwal et al. , 2019). The test is simple, affordable, rapid and minimally invasive (LIGHT, 2010). ADA levels greater or equal to 40 IU/L are associated with a sensitivity of 87.8 to 97.6% and specificity of 90.4 to 92.4 % (Huan et al. , 2021). However, in low and middle income settings the test hasn’t been embraced because of laboratory inadequacies and lack of knowledge about it, and fear of false positives, majorly malignancy, empyema, Para-pneumonic, collagen diseases, (Valdés et al. , 1993) and rheumatoid pleuritis (Hooper, Lee and Maskell, 2010).We present and discuss a case of TBP diagnosed by pleural ADA, in a 28-year-old woman who acquired symptoms during pregnancy through delivery. We also put forward the advantage and applicability of this test amidst lack of thoracoscopy services in Uganda and other low resource settings.
