Eosinophilic effusions

Eosinophilic effusions Eosinophilic pleural effusion is an uncommon disorder characterized by a very high number of eosinophils, usually more than 10% of the cells. Some cases occur in the setting of a predisposing cause, but in about one-third of cases the origin remains obscure. Most cases resolve spontaneously. Eosinophilic pericardial and peritoneal effusions are even […]

Rheumatoid pleuritis

Less than 5% of patients with rheumatoid arthritis develop pleural involvement. The effusion can be unilateral or bilateral and a pericardial effusion may also occur in some cases. The cytologic picture is very characteristic. Abundant clumps of granular debris Macrophages The abundant granular material can stain green, pink, red or orange with the Papanicolaou stain, […]

Systemic lupus erythematosus (SLE)

Systemic lupus erithematosus (SLE) About one-third of patients with SLE develop a pleural or pericardial effusion, or less commonly a peritoneal effusion. The characteristic cell is the lupus erythematosus (LE) cell, a neutrophil or macrophage containing an ingested cytoplasmic particle called hematoxylin body. The hematoxylin body can be green, blue or purple with the Papanicolaou […]

Non-neoplastic conditions

Non-neoplastic conditions In many benign disorders, effusions show a non-specific cytologic picture. However, some conditions are characterized by specific cytologic features which may be helpful in the differential diagnosis. Acute serositis Eosinophilic effusions Tuberculosis pleuritis Rheumatoid pleuritis Systemic lupus erithematosus (SLE) Effusions due to pulmonary infarct Reactive mesothelial cells (often) Mitoses Haemosiderinophages Eosinophils (up to […]

Acute serositis

Acute serositis Acute pleuritis, pericarditis and peritonitis are usually the result of a bacterial infection. Bacterial infection of the pleura occurs in the setting of pneumonia, secondarily involving the overlying pleura and resulting in a pleuric empyema. Acute infection of the peritoneal cavity is often secondary to inflammation of or injury to the bowel, as […]

Tuberculosis pleuritis

Tuberculosis pleuritis 80-100% lymphocytes No or few mesothelial cells Pleural effusions in patients with tuberculous pleuritis have a characteristic, but not specific, cytologic appearance. The fluid is turbid and greenish-yellow. Cytologic preparations are highly cellular and composed almost exclusively of dispersed small lymphocytes, which immunophenotyping shows to be T cells. Mesothelial cells and histiocytes are […]

Physiopathology of the effusions

Physiopathology of the effusions The pleural, pericardial and peritoneal cavities are lined by a single layer of flat or cuboidal mesothelial cells called the serosa. In normal conditions these cavities contain only a small amount of fluid, enough to lubrificate the adjacent visceral and parietal surfaces as they move over each other. In disease states, […]

Malignant effusions

Malignant effusions Some tumours have a greater tendency than others to spread to the serosal cavities. The most common causes of malignant pleural effusion are lung cancer in men and breast cancer in women. In some cases, a malignant pleural effusion can be the first manifestation of lung cancer, whereas it is very uncommon for […]

Specimen collection

Specimen are obtained by inserting a needle into the pleural space (thoracentesis), pericardial space (pericardiocentesis) or peritoneal cavity (paracentesis). Less commonly, fluid is obtained by suction during thoracic or abdominal surgery. Fluid is collected in clean containers and sent unfixed to the laboratory. To prevent clotting, which widely disperses cells, thus hindering their evaluation, fluid […]

Malignant mesothelioma

Malignant mesothelioma Malignant mesothelioma arises most commonly in the pleura and rarely in the peritoneum. The occurrence of this tumour is related to asbestos exposure. The tumour grows as multiple plaques and large nodules on the serosal surface. Most patients have an effusion at the time of presentation. The effusion is often bloody; if not, […]