7/29/2014
Microscopic Veterinary
Pathology
Bruce Williams, DVM, DACVP
Joint Pathology Center
Email: [email protected]
What is O/C?
•a clear description that leads the reader to the
diagnosis (what we might call style)
•clear understanding and separation of primary vs
secondary lesions
•correct use of scientific terminology (where parasites,
etc. come in)
Be concise.
There is no one way to
describe a slide.
Develop a style that is
comfortable and
consistent.
There is no one way to
describe a slide.
Develop a style that is
comfortable and
consistent.
Be concise.
Cutaneous lipoma, dog
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Avoid redundancy or
unnecessary verbiage. Make
each word count.
Be concise.
“Red in color”
“Characterized by”
“vague, poorly defined streams and
bundles”
“associated with”
“three natural and one cut borders”
Caliciviral pneumonia, cat
For example:
“Renal tubular epithelial cells are multifocally necrotic,
characterized by pyknotic nuclei and increased
cytoplasmic eosinophilia.” (114 letters)
“Tubular epithelial cells multifocally have pyknotic
nuclei and hypereosinophilic cytoplasm (necrosis).”
(89 letters)
25 letters/sentence x 10 sentences/description x 20
descriptions = 5000 letters!
instead of using more words,
use better words…
“multifocal”
vs.
“irregularly studded throughout” “centrally
clustered” “random patchy”
“circumferential aggregates of”
Describe in an “inverted
pyramid”, or from big to
little.
Place the main event
first.
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Write with the reader in
mind.
“Just because you SEE it
all doesn’t mean you
have to SAY it all…”
The little things are
important.
Spelling
Punctuation
Grammar
Handwriting
TIMING IS
EVERYTHING.
List the tissue first.
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
Liver. There are random areas….

Adrenal gland, cortex. There is a…

Skeletal muscle with adipose tissue
and fragments of squamous epithelium
(tongue).
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Describe organs in a consistent
manner. (Break each organ into
components for ease of
description.)
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Kidney
Describe components.
Lung
 Glomeruli
 Tubules
 Interstitum
 Vasculature
 Capsule
 Alveolar space
 Alveolar wall
 Airways
 Vasculature
 Pleura and
interstitum
Parainfluenza pneumonia, alveolar spaces, ox
Describe components.
Parainfluenza pneumonia, alveolar septa, ox
Describe components.
Parainfluenza pneumonia, vessel, ox
Describe components.
Parainfluenza pneumonia, airway, ox
Describe components.
Parainfluenza pneumonia, interstitial
emphysema and edema, ox
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Describe components.
Describe components.
Pneumonyssus simicola, lung, rhesus monkey
Morbilliviral pneumonia, dolphin
Describe components.
Dirofilaria immitus, lung, dog
Describe components.
Intestinal amyloidosis, rhesus monkey
Describe components.
Villar endarteritis, pulmonary artery, dog
Don’t reinvent the
wheel.
Sperm granuloma, dog.
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Don’t reinvent the
wheel.
Toxocara canis larval granuloma, kidney, dog.
Don’t reinvent the
wheel.
Cutaneous habronemiasis, horse.
Don’t reinvent the
wheel.
Cholesteatoma, horse.
Don’t reinvent the
wheel.
Calcinosis circumscripta, dog.
Don’t reinvent the
wheel.
Cholesteatoma, horse.
Don’t reinvent the
wheel.
Coffee senna toxicosis, skeletal muscle, ox.
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7/29/2014
Don’t reinvent the
wheel.
Coffee senna toxicosis, skeletal muscle, ox.
Don’t reinvent the
wheel.
Don’t reinvent the
wheel.
Coffee senna toxicosis, skeletal muscle, ox.
Terminology
Coffee senna toxicosis, skeletal muscle, ox.
Terminology
Infectious bursal disease, chicken
Normal bursa, chicken
Terminology
Accessory sex glands, guinea pig
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Terminology
Terminology
Eosinophilic myositis, ox
Terminology
Simian hemorrhagic fever, spleen, rhesus monkey
Terminology - nematode
Pelodera larva, hair follicle, dog
Eosinophilic myositis, ox
Terminology - nematode
Spirocerca lupi adult, esophagus, dog
Terminology - nematode
D. immitis microfilaria, cutaneous vessel, dog
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Terminology - nematode
A. abstrusus adult, larva, eggs, lung, dog
Terminology - cestode
H. nana, small intestine, mouse
Terminology - cestode
Echinococcus granulosus, lung, camel
Terminology - cestode
Cross-section of C. fasciolaris, rat
Terminology - cestode
Mesocestoides sp., abdominal effusion, dog
Terminology - trematodes
Paragonimus kellicotti, lung, cat
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Terminology - arthropods
Pneumonyssyus simicoli, lung, rhesus monkey
Terminology - apicomplexans
Klossiella equi, kidney, horse
Terminology - apicomplexans
Encephalitozoon cuniculi, brain, rabbit
Terminology - apicomplexans
Eimeria furonis, bile ductules, liver, ferret
Terminology - apicomplexans
Toxoplasma gondii, liver, cat
Terminology - apicomplexans
Encephalitozoon cuniculi, kidney, dog
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Terminology - protozoans
Trypanosoma cruzi, heart, dog
Terminology - fungi
Aspergillus fumigatus, lung, horse (GMS)
Terminology
Mouse hepatitis virus infection, liver, nu/nu mouse
Terminology - fungi
Aspergillus fumigatus, lung, horse
Terminology - fungi
Zygomyces, lung, small clawed otter
Terminology
Glioblastoma multiforme, cerebrum, rhesus
monkey
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Terminology
Streptococcus pneumoniae, pleura, guinea pig
Terminology
Mycobacterium tuberculosis, brain, monkey
Terminology
Polyarteritis nodosa, mesentery, rat
Terminology
Pasteurella hemolytica, lung, ox
Terminology
Polyarteritis nodosa, mesentery, rat
Terminology
Thiamine deficiency, cerebrum, ox
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Terminology
You must not only describe,
but also INTERPRET.
“…eosinophilic, beaded material (fibrin)…”
hepatocytes with hypereosinophilic condensed
cytoplasm and pyknotic/karyorrhectic nuclei
(necrosis)…”
…20um round cells with numerous brightly
eosinophilic cytoplasmic granules (globule
leukocytes)…”
Vitamin E deficiency, cerebrum, prenatal guinea
pig
Interpretation
Feline infectious peritonitis, hepatic capsule, cat
Interpretation
Interpretation
Rift Valley Fever, liver, sheep
When all else fails....
Do not panic. No one gets every slide.
If you don’t recognize the tissue, think
reproductive.
Back to the basics
“Is there a color change somewhere on the slide?”
“Is something thinner or thicker than normal?”
“Is something added or lost?”
Listeria monocytogenes, brainstem, horse
Learn from your mistakes (not valid in Ames or
Hannover)
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Back to the basics
Hypothyroidism, skin, dog
Back to the basics
Light-induced retinal degeneration, rat (control on
right)
Back to the basics
In utero bovine pestivirus infection, cerebellum, calf
Back to the basics
Acanthosis nigricans, skin, Dachshund
Back to the basics
Myofibrillar hypoplasia, quadriceps muscle, pig
Back to the basics
In utero bovine pestivirus infection, cerebellum, calf
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Back to the basics
NEOPLASMS
Ehlers-Danlos syndrome, skin, dog
Sentence One.
Sentence One.
Location
Size (a powerful descriptor)
Shape (a powerful descriptor)
Cellularity
Demarcation
Expansile or infiltrative
Encapsulation
Multiple neoplastic cell populations
Shape
Shape
You have already identified the tissue.
Is it restricted to one anatomic site in the
tissue (i.e., grey matter vs. white matter,
epidermis vs. dermis
Does it extend to cut borders
Canine cutaneous spindle cell sarcoma, dog
Apocrine cystadenoma, skin, dog
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Shape
Shape
Canine cutaneous histiocytoma, dog
Shape
Transmissible venereal tumor, penile mucosa, dog
Shape
Fibropapilloma, skin, green sea turtle
Cellularity
Sebaceous epithelioma, skin, ferret
Cellularity
Renal cell carcinoma, kidney, dog
Fibromatous epulis, gingiva, dog
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Cellularity
Demarcation
Fibroma durum, skin, dog
Demarcation
Sebaceous epithelioma, skin, dog
Demarcation
Perianal adenoma, skin, dog
Expansile or infiltrative
Trichofolliculoma, skin, guinea pig
Adrenocortical adenocarcinoma, ferret
Expansile or infiltrative
Chordoma, cervical vertebra, ferret
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Expansile or infiltrative
Intestinal adenocarcinoma, ileum, dog
Encapsulation
Islet cell tumor, pancreas, ferret
Multiple cell population
Ganglioneuroblastoma, adrenal gland, dog
Encapsulation
Interstitial cell tumor, testis, dog
Multiple cell population
Giant cell tumor of bone, cat
Multiple cell population
Fibroepithelial hyperplasia, mammary gland, cat
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Sentence two.
Cellular patterns
Cellular pattern
Carcinoma - nests, packets, lobules
Adenocarcinoma - tubules, acini
Sarcomas - bundles, streams, whorls
Round cell tumors - sheets
Avoid mixing terms from various
categories; it confuses the reader.
Stroma - very important.
Squamous cell carcinoma, periorbital, ox
Cellular patterns
Cellular patterns
Squamous cell carcinoma, periorbital, ox
Cellular patterns
Plasmacytoma, skin, dog
Chemodectoma, dog
Cellular patterns
Nasal adenocarcinoma, sheep
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Cellular patterns
Mammary adenocarcinoma, cat
Cellular patterns
Metastatic cholangiocellular carcinoma, lymph
node, dog
Cellular patterns
Hemangiopericytoma, skin, dog
Cellular patterns
Gastric adenocarcinoma, dog
Cellular patterns
Vaccine-induced sarcoma, skin, cat
Cellular patterns
Meningioma, cat
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Cellular patterns
Dysgerminoma, ovary, dog
Cellular patterns
Malignant melanoma, oral cavity, dog
Other pattern descriptors
Peripheral nerve sheath tumor, dog
Cellular patterns
Malignant melanoma, oral cavity, dog
Other modifiers
Mast cell tumor, skin, dog
Other pattern descriptors
Multilobular tumor of bone, skull, dog
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Other pattern descriptors
Other pattern descriptors
Apocrine adenocarcinoma of the anal sac, dog
Stroma
Granulosa cell tumor, ovary, dog
Stroma
Ciliary body adenocarcinoma, dog
Stroma
Mesothelioma, testis, F344 rat
Stroma
Intestinal adenocarcinoma, ox
Myxosarcoma, skin, dog
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Sentence three
Cell shape
Cell characteristics
Shape (a powerful descriptor)
Size (a powerful descriptor)
Cell borders
Cytoplasmic characteristics
Amount
Color
Character
Nasal adenocarcinoma, sheep
Cell shape
Cell shape
Bronchiolar adenocarcinoma, lung, rat
Size - a powerful
descriptor!
Rhabdomyosarcoma, skin, rat
Cell borders
Transmissible venereal tumor, dog
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Cell borders
Cell borders
Interstitial cell tumor, testis, dog
Cytoplasm
Choroid plexus papilloma, dog
Cytoplasm
Xanthoma, skin, monkey
Cytoplasm
Granular cell tumor, dog
Cytoplasm
Chemodectoma, dog
Signet ring carcinoma, stomach, dog
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Sentence four
Nuclei
Nuclear features
Shape
Size
Location in cell
Chromatin pattern
Nucleolar features
Size
Number
Color
Malignant lymphosarcoma, lymph node, ferret
Nuclei
Nuclei
Mast cell tumor, skin, ferret
Nuclei
Sebaceous carcinoma, skin, dog
Nuclei
Fibroma, skin, dog
Seminoma, testis, dog
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Nuclei
Nuclear Atypia
Schwannoma, eyelid, ferret
Nuclear atypia
Anaplastic mast cell tumor, skin, dog
Nuclei
Malignant melanoma, dog
Nucleoli
Implantation site, presymplasma, ferret
Nucleoli
Melanoma, oral cavity, dog
Melanoma, oral cavity, dog
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Sentence five
Mitotic figures
Mitotic rate
“Mitoses are __ per __ HPF.”
“Mitoses range from __ to __ per HPF, averaging
__ per HPF.”
1 HPF = 40X
If less than 1/10 HPF, then mitoses are RARE.
Presence of atypical mitotic figures
Cholangiocellular carcinoma, cat
Mitotic figures
Sentence six
Unique features of neoplastic cells
Multinucleate
Anisokaryosis
Anisocytosis
Keratinization
Secretion or production
Cytoplasmic invaginations
Etc.
Retinoblastoma, mouse
Unique features
Hemangiosarcoma, spleen, dog
Unique features
Reed Sternberg cell, malignant lymphoma, cat
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Unique features
Unique features
Osteosarcoma, dog, ox
Unique features
Mixed salivary gland tumor, dog
Sentence seven
Evidence of malignancy (if not present,
then just omit this sentence.)
Vascular invasion
Capsular invasion
Necrosis
Hemorrhage
Mast cell tumor, skin, dog
Evidence of malignancy
Gastric adenocarcinoma, dog
Evidence of malignancy
Adrenocortical carcinoma, ferret
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Evidence of malignancy
Sentence eight
(and more if necessary)
Clean up
Inflammation
Ulceration
Hemorrhage
Mineralization
Changes not associated with the neoplasm
Malignant melanoma, skin, dog
INFLAMMATORY
LESIONS
Sentence one.
Location
You have already identified the tissue
Is it restricted to one anatomic site in the
tissue (white matter vs. grey matter,
epidermis vs. dermis)
Extend to cut borders?
Distribution (focal, diffuse, etc.)
Size and shape (powerful descriptors!)
Location and distribution
Afghan myelopathy, spinal cord, dog
Location and distribution
Selenium toxicosis, spinal cord, pig
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Location and distribution
Location and distribution
Lymphocytic bronchiolitis, lung, pig
Location and distribution
Eimeria stiedae, liver, rabbit
Distribution
Old dog encephalitis with demyelination,
b l
Rhodococcus equi, lung, foal
d
Distribution
Distribution
Clostridium piliforme, liver, foal
Myelomalacia, gray matter, spinal cord, dog
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Distribution
Fibrocartilaginous embolism, spinal cord, dog
Distribution
Histoplasma capsulatum, lung, cat
Distribution
Distribution
Aspergillus fumigatus, lung, penguin
Distribution
Infectious laryngotracheitis, trachea, chicken
Inflammatory components
Inflammatory cells
List all cell types in order of prevalence.
List cell types by name. (The terms “mononuclear
infiltrate”, “non-suppurative inflammation”, and
abbreviations such as PMN, RBC, etc are not
acceptable for formal description.
Quantify everything
Interpret your findings.
Clostridium colinum, small intestine, quail
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Inflammatory components
Brucella suis infection, testis, pig
Inflammatory components
Atypical interstitial pneumonia, lung, ox
Inflammatory components
Brugia malayi, skin, ferret
Inflammatory components
Dermatosis vegetans, lung, pig
Inflammatory components
Clostridium piliforme, liver, rabbit
Inflammatory components
Ethmoid hematoma, nasal passage, horse
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Inflammatory components
Chronic obstructive pulmonary disease, lung, horse
Inflammatory components
Amyloid, liver, duck (polarized)
Quantify everything
Inflammatory components
Islet amyloidosis, pancreas, clouded leopard
Inflammatory components
Barium, lung, monkey (left - HE, right - polarized)
Interpret your findings
Small amount (few)
Moderate amount
Large amount (many)
Myriad
Innumerable
Four
Pneumonyssus simicola, lung, rhesus monkey
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Interpret your findings
Avian encephalomyelitis, cerebrum, chicken
Causative agent
Interpret your findings
Cryptosporidium sp., bursa, chicken
Causative agents
Location
Intraepidermal, intracellular, extracellular, intraluminal
Within what types of cells (Kupffer cells, macrophages, etc.)
Size and shape (both powerful descriptors)
Interpretation (bacteria, fungal hyphae, amoebae, etc.
Inclusion bodies
Color (red, basophilic, amphophilic)
Location (intranuclear, intracytoplasmic)
Size and shape (both powerful descriptors)
Trichosomoides crassicauda, urinary bladder, rat
Causative agents
Capillaria aerophila, trachea, cat
Causative agent
Toxoplasma gondii, lung, cat
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Causative agent
Actinomyces sp. (sulfur granule), thoracic cavity,
dog
Causative agent
Feline herpesvirus, tonsil, cat
Formulating a Morphologic
Diagnosis
Causative agent
Canine morbillivirus, lung, ferret
Causative agent
Porcine betaherpesvirus, nasal mucosa, pig
Formulating a Morphologic
Diagnosis
Site (should match the site of your description)
Lesion (be specific with your modifiers)
“Nephritis, plasmacytic”
“Dermatitis, superficial and eosinophilic”
Duration (acute, subacute, chronic)
Distribution (focal, diffuse, etc.)
Severity (minimal, mild, moderate, severe)
The “Withs” - significant findings which support your
diagnosis
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The “Withs”
Two or more related lesions which combine to
result in a single morphologic diagnosis.
•Proliferative and eosinophilic mesenteric
arteritis with aneurysm formation
•Necrotizing vasculitis with dermal infarcts
Examples: Scrapie
“Good” morphologic diagnosis
Cerebellum; brainstem: Neuronal
vacuolation, diffuse, mild, with mild gliosis
and axonal degeneration, Suffolk, ovine.
“Bad” morphologic diagnosis
Encephalopathy, spongiform, Scrapie agent.
Examples: Cirrhosis
Morphologic Diagnosis
“Good” morphologic diagnosis
Liver: Hepatitis, chronic, diffuse, moderate,
with hepatocellular degeneration and loss,
minimal biliary hyperplasia, canalicular
cholestasis, nodular regeration, and
hemosiderosis, Skye Terrier, canine
Neoplasms
“Bad” morphologic diagnosis
Cirrhosis, diffuse
Site
Type of Neoplasm
Examples
Haired skin, ear: Histiocytoma, canine.
Kidney, cortex: Renal cell carcinoma, DSH, feline.
Eye, ciliary body: Melanoma, Boxer, canine.
Questions?
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