INTERPRETATION OF H&E STAINING 1:
CELL INJURY AND INFLAMMATION
SCPA 603- Histopathological Techniques for Routine and Research
Somphong narkpinit, M.D. Department of Pathobiology Faculty of Science Mahidol University
Interpretation of H&E staining 1:
CELL INJURY
Stages in the cellular response
Reversible and Irreversible Cell Injury
Reversible cellular changes & accumulations
Hydropic degeneration (hydropic change)
- Only the cytoplasm is involved
- Water accumulates & the cell swells
- Large vacuoles in the cytoplasm
- Light microscopy
- Cytoplasm is pink & granular
- Electron microscopy (ultrastructural)
- Organelles are swollen
- Ribosomes displaced
- Lysosomal activity very apparent
Intracellular Accumulations
Intracellular accumulation of abnormal amounts of various substances.
(1) a normal cellular constituent accumulated in excess, such as water, lipids, proteins, and carbohydrates
(2) an abnormal substance, either exogenous, such as a mineral or products of infectious agents, or endogenous, such as a product of abnormal synthesis or metabolism
(3) a pigment.
Reversible cellular changes & accumulation
Hyaline change
- Homogenous , glassy , eosinophilic appearance in H&E
stained tissue sections
- Caused most often by nonspecific accumulations of proteinaceous material
- Ex. Glomeruli tufts in diabetic glomerulosclerosis
Reversible cellular changes & accumulations
Accumulation of exogenous pigments
- Naturally colored substances not requiring tissue stain to be seen
1 - Pulmonary accumulations of carbon , silica & iron dust
2 - Plumbism ( lead poisoning)
3 - Algeria ( silver poisoning)
- May cause a permanent gray discoloration of the skin & conjunctiva
Accumulation of endogenous pigments
- Melanin :
- Most common ; brown pigment
- Formed from tyrosine via tyrosinase
- Synthesized in melanosomes of melanocytes within
the basement membrane of the epidermis &
choroid of the eye.
- Transferred by melanocytes to adjacent clusters of
keratinocytes & macrophages (melanophores) in
the subjacent dermis
- Seen also in neoplasm
- Ex. Melanocytic nevus, melanotic macule
- Ex. Melanoma
- Bilirubin
- Catabolic product of the heme of hemoglobin &
myoglobin
- In pathologic conditions , accumulates & stains the blood,
sclera, mucosa , & internal organs producing a yellow
discoloration ( jaundice)
- Hemolytic jaundice
- Destruction of red blood cells.
- Obstructive jaundice
- intra or extrahepatic obstruction of the biliary tract.
- Hepatocellular jaundice Ex. Parenchyma liver damage
- Hemosiderin
- Iron – containing pigment , aggregates of ferritin
- In tissue appears as golden – brown amorphous
aggregates.
- Prussian blue dye – positive blue color stain
reaction.
- Exists normally in small amounts as physiologic
iron stores within tissue macrophages of the bone
marrow, liver, & spleen.
Hemosiderin Melanin
Lipofuscin
- yellowish to light brown, fat-soluble pigment; end
product of membrane lipid peroxidation
- “Wear & tear” pigment
- Commonly accumulates in elderly patients
- Found most often within hepatocytes &
at the poles of nuclei of myocardial cells.
Brown atrophy :
- accumulation of lipofuscin & atrophy of organs
Cardiac muscle Liver
NECROSIS
• There is denaturation of intracellular proteins and enzymatic digestion of the cell.
• The enzymes are derived either from the lysosomes of the dead cells themselves, in which case the enzymatic digestion is referred to as autolysis, or from the lysosomes of immigrant leukocytes, during inflammatory reactions.
Nuclear changes in necrotic cells:
• Karyolysis-basophilia of chromatin may fade.
• Pyknosis-nuclear shrinkage and increased basophilia.
• Karyorrhexis-nuclear fragmentation.
• Disappearance of nucleus.
Normal cell
Reversible cell injury with cytoplasmic & organelle swelling, blebbing & ribosome detachment Irreversible cell
injury with rupture of membrane & organelles, & nuclear pyknosis
Karyorrhexis Karyolysis
Morphology of necrosis.
Necrotic cells show
• increased eosinophilia with a glassy homogeneous appearance.
• The cytoplasm becomes vacuolated and appears moth-eaten.
• Finally, calcification of the dead cells may occur.
Necrosis
• Definition
• Death of groups of contiguous cells in tissue or organ
• Patterns
• Coagulative
• Liquefactive
• Caseous
• Fat necrosis
• Gangrene
Coagulative necrosis
Necrosis Normal
Coagulative necrosis
Liquefactive necrosis
Caseous necrosis
Caseous necrosis
Fat necrosis
Fibrinoid necrosis
Special form of necrosis, visible by light microscopy
Fibrin-like--- in immune reactions
Gangrenous necrosis
Apoptosis
•Programmed cell death.
•Noxious stimuli that damage DNA result in nuclear dissolution without complete loss of cell membrane integrity.
•Can be physiologic or pathologic.
Apoptosis - pathological
Graft-versus-host disease in colonic mucosa
Interpretation of H&E staining 1:
INFLAMMATION
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Morphological classification of acute inflammation
Based on the exudate
Serous Fibrinous Purulent
Hemorrhagic Gangrenous
Patterns of Inflammation Serous Inflammation
Marked by outpouring of thin fluid
From blood serum, e.g. burn blisters
Effusion from mesothelial cells lining the pleural, peritoneal and pericardial cavity
Fibrinous Inflammation
A feature of pericardial and peritoneal inflammation
Vascular permeability allows larger molecules like fibrin to pass or procoagulant stimulus exists in the interstitium (e.g. cancer cells)
Suppurative Inflammation
Characterized by production of large amount of pus composed of neutrophils, necrotic cells and edema fluid
Involves pyogenic bacteria e.g. Streptococci and Staphylococcus aureus
Abscesses are focal localized collections of purulent inflammatory tissue caused by suppuration.
Ulcers
Local defect or excavation of the surface of an organ or tissue by sloughing of inflammatory necrotic tissue
Acute stage - intense polymorphonuclear infiltration and vascular dilation in margin
Chronic stage - margin and base develop fibroblastic proliferation, scarring and accumulation of lymphocytes, plasma cells and macrophages
Morphologic Patterns of Acute Inflammation
FIBRINOUS INFLAMMATION
A fibrinous exudate is characteristic of inflammation in the lining
of body cavities, such as the meninges, pericardium and pleura
Purulent inflammation
Characteristics
fibrin and neutrophil-rich exudate abscess: demarcated pus in tissue phlegmone: pus spreading in tissue empyema: pus in a body cavity
Examples purulent meningitis pneumonia (fibrinopurulent) erysipelas (S. pyogenes) purulent pyelonephritis
Brain Abscess
Localized liquefactive necrosis liver abscess
Removal of the dead tissue leaves behind a scar
Hemorrhagic inflammation Characteristics
large amount of blood in exudate
Examples haemorrhagic cystitis: BK cystitis, cyclophosphamide
plague: Yersinia pestis (G-negative), rats disseminate
bubonic plague: lymph node enlargement, lung plague: hemorrhagic pneumonia anthrax: Bacillus anthracis (G-pozitíi)e, bioterrorism! skin anthrax - ulcer sepsis; lung anthrax - hemorrhagic pneumonia uremic pericarditis
Gangrenous inflammation
Characteristics
purulent inflammation + ischemic necrosis
Outcome of acute inflammation
Full recovery
minimal tissue necrosis/exudate tissue capable of regeneration minimal organisation and scar Scarring
significant necrosis or exudate limited regeneration capability fibrosis/sclerosis - connective tissue accumulation
Persistent inflammation chronic inflammation
mononuclear inflammatory cells granulation tissue and fibrosis active chronic inflammation - neutrophils and chronic inflammation
Reparation
• tissue necrosis (eg. infarct)
• neutrophil granulocytes (acute inflammation, 18-20 hours) • macrophages (24-48 hours) (matrix metalloproteases, others) • fibroblast-activation (TGFβ, PDGF) • fibrosis -scar (weeks)
granulation tissue: fibroblasts, macrophages, angiogenesis
Scarring
Callus pleurae
fibrous pleuritis pleural fibrosis
Cirrhosis pseudolobular scarring Ito-cell activation
Acquired valve disease chronic endocarditis scarring after previous inflammation
Chronic inflammation
General characteristics Examples Granuloma
causes definitions chronic gastritis
cells of chronic mechanism rheumatoid arthritis
inflammation types
mediators of chronic inflammation
Chronic inflammation
Characteristics
prolonged (weeks/months) inflammation mononuclear inflammatory cells reparation non-specific / specific
Causes
prolonged acute inflammation autoimmune inflammation viral infection
difficult to degrade foreign materials
MORPHOLOGIC FEATURES OF CHRONIC
INFLAMMATION
1. Infiltration with mononuclear cells include Macrophages
Lymphocytes
Plasma cells
Eosinophils
2. Tissue destruction induced by the persistent offending agent or by the
inflammatory cells.
3. Healing by connective tissue replacement of damaged tissue,
accomplished by proliferation of small blood vessels (angiogenesis) and, in particular, fibrosis
Granuloma Definition
circumscribed chronic inflammation with many, activated macrohages
Causes
material degradable Tuberculosis Fungal infection Unknown
TH1 immune response (type IV hypersensitivity) - caseous necrosis
foreign body Langhans Touton type giant cell type giant cell type giant cell
Granuloma types, examples
Non-immune granuloma Lipogranuloma Foreign-body granuloma
Xanthogranulomatous inflammation Necrobiosis (NL, GA, RN)
Immune granuloma Tuberculosis Leprosy Syphilis Cat scratch disease
Fungal infection (Histoplasma, Cryptococcus, etc.)
Unknown pathomechanism Sarcoidosis
Disease Cause Tissue Reaction
Tuberculosis
Mycobacterium tuberculosis
Noncaseating tubercle Caseating tubercles
Leprosy
Mycobacterium leprae
Acid-fast bacilli in macrophages; noncaseating granulomas
Syphilis Treponema pallidum
Gumma: wall of histiocytes; plasma cell
Cat-scratch disease
Gram-negative bacillus
Rounded or stellate granuloma
Sarcoidosis
Unknown etiology
Noncaseating granulomas
Crohn disease Immune reaction against intestinal bacterial
dense chronic inflammatory infiltrate with noncaseating granulomas
Examples of Diseases with Granulomatous Inflammations
