Indonesia is one of country that contributes the most cases of tuberculosis worldwide. Tuberculosis is the most commonly etiology of exudative pleural effusion. There have been many studies about undiagnosed exudative pleural effusion, but there are not many studies about the use of medical thoracoscopy for diagnosing transudative and exudative pleural effusion, especially on biomarkers of C-Reactive Protein (CRP), D-dimer, Adenosine Deaminase (ADA), Antinuclear Antibody (ANA), C3 C4 complements, Cancer Antigen 125 (CA-125), Xpert Mycobacterium Tuberculosis (Xpert MTB), Lupus Erythematosus cell (LE cell), cytology (effusion and smear) and histopathology. Information gained from those biomarkers via thoracenthesis and medical troracoscopy, etiology of exudative and transudative pleural effusion can be detected earlier and clearly, especially etiology of infection, autoimmune, and malignancy that further can be used to reduce patients' hospitalization period, mortality, and to develop the new therapeutic agents.

Medical thoracoscopy is a minimally invasive procedure to access pleura with combination of visual and medical instrument. The procedure is performed under local anesthesia and conscious sedation. Medical thoracoscopy plays role in basic diagnotic and therapeutic. The most common indication on basic diagnostic is on pleural effusion case that has primary target to get specific diagnosis when the etiology of pleural effusion is unknown. Pleural effusion is fluid accumulation inside the pleura for about 15-20 ml. Primary aim of pleural effusion diagnosis is to differentiate exudative and transudative effusions based on Light Criteria. Most of time thoracentesis cannot give etiology of exudative and transudative pleural effusion.

Researchers will evaluate subjects based on inclusion and exclusion criteria in Cipto Mangunkusumo Hospital. Furtehrmore, research subjects will be asked for informed consent. Data will be collected based on research form. Researcher will perform medical thoracoscopy to take specimen for analysing CRP, D-dimer, ADA, ANA, C3 C4 complements, Xpert MTB, LE cell, cytology (effusion and smear) and histopathology to detect the etiology of tuberculosis, malignancy or autoimmune.

Inclusion Criteria:

• Hospitalized adult age 18 - 75 years old
• Willing to be involved in the research
• Undiagnosed transudative and exudative pleural effusion post-thoracentesis twice on right and left lung
• Patients can undergo medical thoracoscopy under local anesthesia, based on ATS and BTS guideline

Exclusion Criteria:

• Pregnant and breastfeeding women
• Patients in non-invasive ventilation and mechanical ventilator
• Transudative and exudative pleural effusion with etiology of chronic heart failure, chronic kidney disease, hepatocirrhosis with or without hepatic hydrothorax and hypoalbuminemia.