Post on 20-Jan-2016
transcript
In the name of
GOD
Asbestos-Related
Disease
Asbestos Exposure General
•Salts of salicic acid
•90% of asbestos in USA is white asbestos (chrysotile)
•Occurs in : Automotive workers-brake linings Shipfitters
Construction workers
Asbestos-Related Disease Types of Fibers
Chrysotile (white asbestos)–benign
Crocidolite (blue/black asbestos) in South Africa/Australia–malignant
Crocidolite-small fibers-associated with most pleural disease
Asbestos-Related Disease Types of Fibers:
SerpentinsChrysotil (white asbestos)
Amphibole
Crocidolith (blue)
Amozith (brown)
Anthophylith
Tremolith
Asbestos-Related Disease Pathophysiology
Asbestos particles invoke a hemorrhagic response in lung
Fibers then coated with a ferritin-like material resulting in ferruginous bodies
Damage to respiratory bronchioles and alveoli
Asbestos-Related Disease Types of
Asbestos-related Pleural Disease
Asbestosis
Asbestos-related Malignancies
Asbestosis(pulmonary parenchymal fibrosis)
1- Almost always involves lower lobes at subpleural areas
2-As the disease progresses, fibrosis and volume loss ensue
3-Honey-combing in lower lobe subpleural areas
4-Tracheobronchial nodal involvement is unusual
5-PMF is very uncommon
Asbestos-Related Pleural Disease
Pleural plaques
Diffuse pleural thickening
Pleural calcification
Pleural Effusion
Asbestos-Related Pleural Disease Incidence of Pleural Disease
Almost all have some pleural involvement Pleural plaque 65% Diffuse pleural thickening 17% Calcification 50% Effusion 21%
Pleural involvement without parenchymal disease is common
Asbestos-Related Pleural Disease
Pleural Plaques-1
Affects submesothelial layer of parietal pleura
Bilateral, mid-lung zone
Between 7th and 10th ribs Diaphragmatic pleura Spares apices
Asbestos-Related Pleural Disease Pleural Plaques-2
Plaques don’t usually calcify
Plaques alone are not associated with malignancy
Appear either in “profile” or “en face”
Asbestos-Related Pleural Disease Diffuse Pleural Thickening-1
Diffuse thickening of parietal pleura Involves diaphragmatic pleura, extends up lateral chest wall Commonly obliterates costophrenic angles
Spares apices of lungs DDX from TB
Asbestos-Related Pleural Disease Diffuse Pleural Thickening-2
Frequently the sequela of benign pleural effusion
Associated with rounded atelectasis
Rounded Atelectasis
Part of peripheral parenchyma invaginated into the penetrating fibrotic visceral pleura, so that part of the parenchyma is entrapped and becomes atelectatic
HRCT findings of Rounded Atelectasis
1-Continuing with areas of diffuse pleural thickening
2-Lenticular or wedge-shaped
3-Comet-tail sign
4-evidence of volume loss in the affected lobe often associated with hyperlucency of the adjuscent lobe
Asbestos-Related Pleural DiseasePleural Effusion
Effusion alone may occur early in disease (first 15 years) in about 3% of cases
Exudative May be associated with chest pain
Involves visceral pleura as well
Does not mean mesothelioma
May be associated with rounded atelectasis
Diagnostic Criteria:
1-Exposure history for asbestos
2- Ruling out other causes
3-Failing to detect tumor in a 3 years follow-up
Pathological description:
Chronic fibrinous pleuritis with low cellularity
Prognosis:
Good with a self-limited course
Recurrence may occur
Asbestosis General
Reserved for parenchymal lung disease
Fibrosis begins around bronchi and progresses outward
Asbestosis
Interstitial lung disease
Rounded atelectasis
Asbestosis Location
More common in lower lungs
More common subpleural
Asbestosis X-ray
Opacities are small and irregularly shaped
Not rounded as in silicosis Prominent septal lines around 2° lobules Cardiac silhouette may become shaggy
Hilar lymph nodes rarely affected DDx from silicosis
Asbestosis HRCT
Multiple subpleural dot-like nodularities=subpleural lines Fibrous bands Subpleural pulmonary arcades Honeycombing Thickened interlobular lines Ground-glass appearance
Asbestos-Related Malignancies
Bronchogenic carcinoma
Mesothelioma Benign
Malignant
Carcinoma of the larynx or stomach
Asbestos-Related Disease Lung Cancer
Either squamous cell or adenocarcinoma
Bronchogenic ca is almost always associated with cigarette smoking
90x more common in smokers, 5x more common in
Frequently at lung base
Associated with increased risk of stomach cancer
non-smokers
Thank you…