De pathologie achter de CTDe pathologie achter de CT

Bronkhorst colloquium 2013-2014Interstitiële longziekten

Katrien Grünberg, klinisch patholoogK.grunberg@vumc.nl

VoorbereidingVoorbereiding

• De opzet van de lezing is om u kennis te laten maken met een aantal histopathologische afwijkingen en patronen. Tijdens de cursus zal verder worden ingegaan op de vertaling van de histologie naar CT.

• Om de histologische afwijkingen van de longen te kunnen herkennen, is kennis van de normale microscopische anatomie essentieel. Neem de volgende dia’s door als U uw kennis wilt opfrissen.

• Vervolgens kunt U zelf aan de slag met 3 casus. Na enkele inleidende dia’s, vindt U de links naar gescande coupes.

Even opfrissenEven opfrissen

• Om de histologische afwijkingen van de longen te kunnen herkennen, is kennis van de normale microscopische anatomie essentieel. Neem de volgende dia’s door als U uw kennis wilt opfrissen.

Alveolar surface area: 143 m2 Capillary surface area: 140 m2

90% Air-blood interface surface area: 126 m2 (70 times skin: 1.8 m2)

Blood content 0.2 L

RBC passes through capillary bed in 0.75 seconds

Lungs are for gas exchangeLungs are for gas exchange

The alveolar-capillary membraneThe alveolar-capillary membrane

CO2

O2

0.6 m

The alveolar-capillary membraneThe alveolar-capillary membrane

O2

CO2

LungsLungs

Core businessCore business• Gas exchange

Infrastructure and LogisticsInfrastructure and Logistics• Conducting airways• Conducting vessels• Innervation• Defence

Alveolar duct – terminal bronchioleAlveolar duct – terminal bronchiole

BronchioliBronchioli

lumen

epithelium

airway smooth muscle

alveoli

pulmonary artery

Bronchovascular bundle

Airway epitheliumAirway epithelium

2 - 3 days

AlveoliAlveoli

Surfactant producing cells:Surfactant producing cells:Type II pneumocytes and Clara cellsType II pneumocytes and Clara cells

Barry R. Stripp et al. Am. J. Respir Cell Molec Biol. 2002;. 27: 170-8

Alveolar surface area: 143 m2

Tracheobronchial liningTracheobronchial lining

Seromuc. Glands

Goblet cell s

surfactant

Lung vasculatureLung vasculature

Alveolar surface area: 143 m2 Capillary surface area: 140 m2

90% Air-blood interface surface area: 126 m2

Blood content 0.2 L

RBC passes through capillary bed in 0.75 seconds

Arteries and veinsArteries and veins

Interlobular septum

Axial artery

Bronchiole Vein

Lymph vessel

ArteriesArteries

• Elastic artery (> 1 mm )– bronchi

• Muscular artery (50-1000 m)– bronchioli

• Arterioles (< 50 m)– Alveolar parenchyma

Bronchus-associated lymphatic tissue Bronchus-associated lymphatic tissue (BALT)(BALT)

Lymph vesselsLymph vessels

D-240

• Around p. arteries• In interlobular septa

The secondary lobuleThe secondary lobule

Pulm artery

Vein

Lymph vessel

Airway

Interlobular septum

Inleiding in histopathologie van ILDInleiding in histopathologie van ILD

ILD is about patternsILD is about patterns

• Type of lesions– Fibrosis– Inflammation

• Distribution

Fibrosis: distributionFibrosis: distribution

• Intersitial or airspace• Centrilobular or subpleural• Basal fields vs upper fields

Lymphatic Centrilobular distribution

InflammationInflammation

• Composition– lymphocytic, plasmacell, neutro/eosinophilic– granulomatous

• Distribution– Interstitial (centrilobular/diffuse) – Bronchiolitis– Vasculitis

InflammationInflammation

CluesClues

• Necrosis• Hyaline membranes (as in diffuse alveolar

damage)• Pigmentation

– Iron (bleeding)– Inhaled stuff

• Funny looking cells and such

Case 1Case 1

• Fibrosis? – Distribution (centrilobular or subpleural?)

• Inflammation?– Type?

• Clues?

• Descriptive diagnosis – Summary of pattern of fibrosis and inflammation, clues

• DD

Case 1Case 1

pleura

→ fibroblast foci

Old and young fibrosis:

temporal heterogeneity

Case 2Case 2

• M 71 yr. History of myocardial infarction.

• Fibrosis? • Inflammation?• Distribution?• Airspaces?

• Pattern• DD

Fibrosis. Where?

Nodular fibrosis. Where? And some infiltrate. Where?

Nodular fibrosis in alveolar spaces: Masson bodies

Lymphocytic infiltrate in alveolar septa (interstitial pneumonitis)

Funny looking alveolar macrophages (foamy)

PatternPattern

• Organizing pneumonia• Mild pneumonitis• Clue: foamy macrophages

General DifferentialsGeneral Differentials

• Infection• Infection

• Vasculitis• Collagen vascular disease / AID / IgG4 • Occupational/recreational toxic stuff (inhaled) • Drugs (iv, otherwise)• Idiopathic fibrosis• Other (inborn)

ClueClue

• Patient used amiodarone

• OP, pneumonitis, foamy macrophages all fit with amiodarone-induced ILD

• http://www.pneumotox.com

Case 3Case 3

• M 75 yr • Fibrosis? (EvG this staining shows fibrosis in red, elastin in black)

– Specifics

• Inflammation?– Specifics

• Distribution?• Pattern• DD

Inflammation, bronchiolocentric

bronchiolocentric inflammation: lymphocytes (T cells)

Clues

Giant cells in poorly formed granulomas

PatternPattern

• Minimal fibrosis• Bronchiolocentric interstitial pneumonia• Clue: poorly formed granulomas

Differential DxDifferential Dx• …

ClueClue

• Patient kept pigeons

EAA – hypersensitivity pneumonitisEAA – hypersensitivity pneumonitis

• Bird fancier's lung • Also called bird breeder's lung, pigeon

breeder's lung, and poultry worker's lung

• Bagassosis• Cephalosporium HP• Cheese-washer's lung• Chemical worker’s lung - Isocyanate HP• Chemical worker's lung[9] - Trimellitic

anhydride (TMA) HP• Coffee worker's lung• Compost lung• Detergent worker's disease• Familial HP• Also called Domestic HP• Farmer's lung• Hot tub lung• Humidifier lung• Japanese summer house HP Also called

Japanese summer-type HP• Laboratory worker's lung• Lycoperdonosis

• Malt worker's lung• Maple bark disease• Metalworking fluids HP• Miller's lung• Mollusc shell HP• Mushroom worker's lung• Peat moss worker's lung• Pituitary snuff taker's lung• Sauna worker's lung• Sequoiosis• Streptomyces HP• Suberosis• Tap water HP• Thatched roof disease• Tobacco worker's lung• Wine-grower's lung• Woodworker's lung

How to bluff your way through interstitial lung diseaseHow to bluff your way through interstitial lung disease

EAA HPUIPNSIPSR-ILD(C)OP(BO)OPDIPRB-ILDDAD

═ Extrinsic allergic alveolitis ═ Hypersensitivity pneumonitis═ Usual interstitial pneumonia═ Non-specific interstitial pneumonia═ Smoking-related interstitial lung disease═ (Cryptogenic) Organizing Pneumonia═ (Bronchiolitis Obliterans) Organizing Pneumonia═ Desquamative interstitial pneumonia═ Respiratory bronchiolitis - ILD═ Diffuse alveolar damage (≈ ARDS)