Pleural effusion due to non-malignant gastrointestinal disease

Although pleural effusion is a frequent finding in clinical practice, determining its etiology may be challenging, and up to 20% of cases remain undiagnosed. Pleural effusion may occur secondary to a non-malignant gastrointestinal disease. A gastrointestinal origin is confirmed based on a review of the medical history of the patient, and thorough physical examination and abdominal ultrasonography. In this process, it is crucial to correctly interpret findings on pleural fluid obtained by thoracentesis. In the absence of high clinical suspicion, identifying the etiology of this type of effusion may be difficult. Clinical symptoms will be determined by the gastrointestinal process causing PE. In this setting, correct diagnosis relies on the specialist's ability to associate pleural fluid appearance, test for the appropriate biochemical parameters, and determine whether it is necessary or not to send a specimen for culture. The established diagnosis will determine how pleural effusion is approached. Although this clinical condition is self-limited, many cases will require a multidisciplinary approach, as some effusions only resolved with specific therapies.