A mesothelial surface lining the lungs and mediastinum

Mesothelial cells designed for fluid absorption

Hallmark of disease is the pleural effusion

THE PLEURA

Transudate (low protein)

cardiac failure

hypoproteinaemia

Exudate (high protein)

pneumonia

TB

connective tissue disease

malignancy (primary or metastatic)

PLEURAL EFFUSION

Full of acute inflammatory cells

Empyema

Can become chronic

PURULENT EFFUSION

Serofibrinous pleuritis

Reflects pulmonary inflamation e.g tuberclosis, pneumonia, infarcts, abcesses or systemic diseases (R.A and uremia)

Supparative pleuritis or empyema

Reflects pleural space infection leading to pus accumulation

Hemorrahgic pleuritis

Occurs with bleeding disorders, neoplastic involvment

VARIOUS PATTERNS MAY BE SEEN

Hemothorax(ruptured aortic aneurysm)

Chylothorax ( collection of milky lymph) due to neoplastic lymphatic obstruction.

NON INFLAMMATORY EFFUSIONS

HEMOTHORAX

Air in pleural space

Trauma

Rupture of bulla

PNEUMOTHORAX

PNEUMOTHORAX

LARGE BULLAE

Primary

benign (rare)

malignant mesothelioma

Secondary

common (adenocarcinomas - lung, GIT, ovary)

PLEURAL NEOPLASIA

Localized

Noninvasive

Fibrosing

Also occur at other sites

Not related to asbestose

Resection is usually curative

SOLITARY FIBROUS TUMOR

Associated with asbestose exposure in 90% cases only 20% have pulmonary asbestosis

MALIGNANT MESOTHELIOMA

Pts present with chest pain, dyspnea and recurrent pleural effusions

Highly malignant tumors that invade the lung and can metastasize widely.

Fewer pts survive longer than 2yrs.

CLINICAL FEATURES

MESOTHELIOMA

http://www.mesothelioma.com/images/pleural-mesothelioma.jpg

PLEURAL BIOPSY - MESOTHELIOMA

Mixed spindle cell

(mesenchymal) and epithelial differentiation

METASTASES IN PLEURA

Cytology,

biopsy

Difficult to diagnose

Immunohistochemistry for lineage specific antigens may help

Medicolegal importance

DIFFERENTIAL DIAGNOSIS OF MALIGNANT EFFUSIONS

http://www.mesothelioma.com/images/pleural-mesothelioma.jpg

REFFERENCES

http://www.mdguidelines.com/empyema/definition

http://treatment-zone.blogspot.com

http://www.medicinenet.com/imagecollection/pneumothorax_picture/picture.htm