Differential Diagnoses for Lymphocyte Predominant Pleural Effusion
Single Most Likely Diagnosis
- Tuberculous pleurisy: This is often the most common cause of lymphocyte-predominant pleural effusion, especially in endemic areas. The high lymphocyte count in the pleural fluid is characteristic of this condition.
Other Likely Diagnoses
- Malignant pleural effusion (lymphoma): Lymphomas, particularly those of lymphocytic origin, can cause pleural effusions with a high lymphocyte count.
- Parapneumonic effusion: Some parapneumonic effusions, especially those associated with certain types of pneumonia, can have a lymphocytic predominance.
- Sarcoidosis: This systemic disease can cause pleural effusions with a high lymphocyte count, although it is less common than other manifestations like pulmonary involvement.
Do Not Miss Diagnoses
- Lymphangitic carcinomatosis: Although less common, this condition, which involves the spread of cancer to the lymphatic vessels of the lung, can cause a lymphocyte-predominant pleural effusion and is critical not to miss due to its poor prognosis.
- Mesothelioma: A rare form of cancer that affects the lining of the lungs, mesothelioma can cause pleural effusions with various cell types, including lymphocytes, and is crucial to diagnose early due to its aggressive nature.
Rare Diagnoses
- Chylothorax: While typically characterized by the presence of chylomicrons in the pleural fluid, some cases can have a lymphocytic predominance, especially if the chyle is not evident.
- Eosinophilic pleural effusion with lymphocytic component: Some conditions that cause eosinophilic pleural effusions, such as parasitic infections or drug reactions, can also have a significant lymphocytic component.
- Castleman disease: A rare lymphoproliferative disorder that can cause pleural effusions with lymphocytic predominance, often as part of a systemic disease process.