Update on tuberculous pleural effusion

Abstract

The possibility of tuberculous pleuritis should be considered in every patient with an undiagnosed pleural effusion, for if this diagnosis is not made the patient will recover only to have a high likelihood of subsequently developing pulmonary or extrapulmonary tuberculosis Between 3% and 25% of patients with tuberculosis will have tuberculous pleuritis. The incidence of pleural tuberculosis is higher in patients who are HIV positive. Tuberculous pleuritis usually presents as an acute illness with fever, cough and pleuritic chest pain. The pleural fluid is an exudate that usually has predominantly lymphocytes. Pleural fluid cultures are positive for Mycobacterium tuberculosis in less than 40% and smears are virtually always negative. The easiest way to establish the diagnosis of tuberculous pleuritis in a patient with a lymphocytic pleural effusion is to generally demonstrate a pleural fluid adenosine deaminase level above 40 U/L. Lymphocytic exudates not due to tuberculosis almost always have adenosine deaminase levels below 40 U/L. Elevated pleural fluid levels of g-interferon also are virtually diagnostic of tuberculous pleuritis in patients with lymphocytic exudates. In questionable cases the diagnosis can be established by demonstrating granulomas or organisms on tissue specimens obtained via needle biopsy of the pleura or thoracoscopy. The chemotherapy for tuberculous pleuritis is the same as that for pulmonary tuberculosis.

É possível diferenciar derrames pleurais linfocíticos secundários a tuberculose ou linfoma através de variáveis clínicas e laboratoriais?

“…2012;38(2):181-187 185 mesothelial cells (< 5%). (18) These characteristics were found in most of the patients investigated in the present study. Pleural effusion secondary to lymphoproliferative diseases constitutes a major cause of malignant effusion.…”

“…(13) From a clinical standpoint, both tuberculosis and lymphoma predominate in males in the second decade of life, although tuberculosis can also affect younger patients. (7,(17)(18)(19) The clinical similarities between tuberculosis patients and lymphoma patients are noteworthy. In both types of patients, complaints are usually related to the magnitude of the effusion and to constitutional symptoms, such as weight loss.…”

“…In both types of patients, complaints are usually related to the magnitude of the effusion and to constitutional symptoms, such as weight loss. (7,18,19) Although dry cough, pleuritic chest pain, and fever were more commonly reported by the patients with tuberculosis, those symptoms were also common in those with lymphoma. Night sweats, a common symptom in patients with pulmonary tuberculosis, (18) were found to be significantly more common in the patients with pleural tuberculosis (60%).…”

“…(14,(16)(17)(18) In addition, ADA levels are commonly increased in the pleural fluid of patients with lymphoma, regardless of the cell subtype (T or B cells). (13) From a clinical standpoint, both tuberculosis and lymphoma predominate in males in the second decade of life, although tuberculosis can also affect younger patients.…”

The advantage of PCR for MTB in comparison to ADA in diagnosing tubercular pleural effusion

“…12,13 A cut off value of >40U/L is usually used to strongly suspect tubercular etiology in a pleural effusion. 14,15 The sensitivity of ADA for diagnosing tubercular pleural effusion has been high and has been reported to be around 90%. 15,16 In our study also the sensitivity of ADA for diagnosis of tubercular pleural effusion has been found to be 85.2% which is comparable to other studies.…”