Introduction to pathology Flashcards
To describe a lesion, include:
- Location
- Number/extent
- Demarcation
- Distribution
- Colour
- Size
- Shape
- Consistency and texture
- Any particular sounds or smells
Differentiate clinical diagnosis from clinical pathological diagnosis
- Clinical diagnosis: based on case history, clinical signs and physical exam. Example: canine parvovirus infection
- Clinical pathologic diagnosis: based on changes observed in chemistry of fluids and haematology. Example: neutropenia
Autolysis
changes due to self-digestion, caused by intracellular enzymes leaking through cell membranes
Putrefaction
colour and textural changes, gas production, and odours that are caused by post-mortem bacterial metabolism and dissolution of host tissues (post-mortem decomposition)
Rigor mortis
contraction of the muscles occurring after death.
This is due to depletion of ATP and glycogen.
This commences 1-6hrs after death and persists for 1-2 days.
Livor mortis
gravitational pooling of blood to the downside of the animal. Can be seen on the surface in light-skinned animals and within organs e.g. the lungs.
Livor mortis
Post-mortem clotting
Clotting that occurs as it would in life, but clots do not adhere to the vessel walls.
This is especially evident in the heart and great vessels, within several hours after death.
Haemoglobin imbibition
Red staining of tissue that occurs once integrity of the blood vessel is lost and haemoglobin is released by lysed erythrocytes.
Haemoglobin imbibition
How does haemoglobin imbibition differ from liver mortis?
- Haemoglobin imbibition = the erythrocytes have been lysed
Bile imbibition
Bile in the gallbladder stains adjacent tissue yellowish/greenish/brown.
Bile imbibition
Pseudomelanosis
Blue-green discolouration of tissue by iron sulphide (FeS).
Formed when hydrogen sulphide generated by putrefactive bacteria and iron from haemoglobin from lysed erythrocytes interacts.
Staining can resemble melanin, hence the name.
Pathogenesis
the process by which a disease or disorder develops
Aetiology
Cause or manner of causation of a disease.
Azotemia is
a) a clinical diagnosis
b) a morphologic diagnosis
c) an aetiologic diagonsis
d) a clinical pathologic diagnosis
Azotemia is
a) a clinical diagnosis
b) a morphologic diagnosis
c) an aetiologic diagonsis
d) a clinical pathologic diagnosis
True/false: thrombosis is a normal finding.
False.
Thrombosis is a pathologic process in response to injury.
It is an interaction between the blood coagulation system and platelets to form a clot in a vascular system.
It relies on this triad:
Which of the following is the same regardless of species or organ system?
a) anatomic pathology
b) systemic pathology
c) pathology
d) general pathology
a) anatomic pathology
b) systemic pathology
c) pathology
d) general pathology
Which of the following is a function of anatomic pathology?
a) blood smear
b) BUN
c) FNA
d) biopsy
a) blood smear
b) BUN
c) FNA
d) biopsy
A chicken fat clot
Caused by the separation of red and white blood cells
Pathology
study of disease; the structural, biochemical and functional changes in cells, tissues, and organs that underlie disease
General pathology
Basic responses of cells and tissues to noxious stimuli/insults and injuries irrespective of the organ/organ systems, species etc. of animal involved
Anatomic pathology
examination of tissues taken during life (biopsy) or death (necropsy). This encompasses histopathology.
Clinical pathology
examination of blood and other body fluids as well as cytology (taken during life)
Classify the following as lesions or artefacts:
- Livor mortis
- Haemoglobin/bile imbibition
- Pseudomelanosis
- Autolysis/putrefaction
These are all artefacts
What does the following liver show?
Autolysis/putrefaction
How do you write a morphologic diagnosis? (European convention)
- Organ
- Severity (mild/moderate/severe)
- Duration (peracute/acute/subacute/chronic/chronic-active)
- Descriptors
- Diagnosis
If it’s a neoplasia, then:
- Organ
- Neoplasia
What is your morphologic diagnosis?
Lungs: pneumonia, suppurative, multifocal, severe, acute.
What is your morphologic description?
There was a raised, well-demarcated, dark red, mottled, soft and irregularly shaped mass measuring X by X cm on the outer wall of the right ventricle, just below the right auricular appendage. Upon incision, the mass oozed a small amount of blood.
What is your morphologic diagnosis?
Heart: right ventricle, haemangiosarcoma.
What is your morphologic diagnosis?
Whole body (likely that if mm and pinna are yellow, so is everywhere else): icterus, diffused, severe, subacute.
Describe this lesion and provide a morphologic diagnosis
Stomach is diffusely distended, gas-filled, and diffusely dark red.
Stomach: necrosis, diffuse, severe and acute with dilation.
What are some reasons why you might perform a post-mortem exam?
- To determine cause of death
- Outbreak investigation
- Forensic investigation (abuse/negligence)
- Zoonoses
- Contribute to knowledge e.g. paper publication
- Assess treatment effects (lab setting)
