Descriptive pathology

Question 1

What needs to be included in a gross pathology description?

Answer 1

Choose MASS, NODULE, LESION then choose your descriptors

• Tissue/organ
• Distribution - focal, multi focal or diffuse
• Size
• Extent or % affected
• Shape
• Contour
• Demarcation – well or poorly demarcated
• Colour
• Texture
• Odour

*Tiny Dogs Sneak Everywhere, Stealing Cheese During Catnap Time Often

Eg. There is a focal, well demarcated, raise, approximately 10cm diameter nodule arising from the splenic parenchyma (nodular hyperplasia v neoplasia v inflammation/ abscess/granuloma). The nodule has a smooth surface and is mottle pale pink/orange to dark red with some regions of pallor within the mass forming smaller, discrete nodules.

Question 2

Examples of things ADDED

Answer 2

Cells
* Inflammatory cells –> look at other changes to indicate acute v chronic
* Parenchymal cells –> consider the tissue; is this hyperplasia or hypertrophy or metaplasia?
* Neoplastic cells
Fluid
* Oedema
* Transudate v exudate
* Blood
Extracellular infiltrate (acellular material)
* Amyloid, mineral, collagen, osteoid and chondroid matrix
Intracellular infiltrate
* Lipid, glycogen are the main ones that will make a tissue noticeably larger
* Lysosomal storage disease
Gas (usually bacterial proliferation and often PM but not always)

Question 3

Examples of things LOST

Answer 3

Usually cells, but can be fluid
The whole organ / tissue is uniformly smaller?
* Atrophy or hypoplasia (easier with paired organs or a control)
* There is an area of depression or indentation or a discrete area of size reduction?
* Atrophy
* Cell death & necrosis +/- fibrosis
* Fluid loss (i.e. dehydration)

Question 4

3 terms we use for distribution

Answer 4

• focal (focally or locally extensive)
• multifocal (multifocal to coalescing)
• diffuse

Question 5

Acronym used for potential causes of disease

Answer 5

PIGMUT
* Physica
* Infectious or inflammatory
* Genetic
* Metabolic
* Unknown
* Toxic

Question 6

2 terms used for demarcation and examples of each

Answer 6

Well demarcated
* Vascular insult
* Benign tumour
* “Walled off” inflammatory insult (eg. granuloma or abscess)
* hyperplastic nodules
Poorly demarcated
* Inflammation
* Malignant neoplasia
* Necrosis
* Something resembling normal tissue ie hyperplasia, hypertrophy, atrophy, neoplasia

Question 7

What is shape indicative of?

Answer 7

Shapes often suggest a vascular lesion or something following a structure ie lymphatics, bronchi, zones of liver

Question 8

What is the colour RED indicative of?

Answer 8

• haemorrhage
• congestion
• hyperaemia
• haemoglobin inhibition

Question 9

What is the colour YELLOW indicative of?

Answer 9

• bilirubin
• haematoidin (Hb breakdown product)
• inflammation

Question 10

What is the colour GREEN indicative of?

Answer 10

• bile staining
• putrefication (rotting tissue)
• oesinophillic inflammation
• necrosis

Question 11

What is the colour WHITE indicative of?

Answer 11

• mineral (ie calcium)
• fat/lipid
• fibrosis
• loss of blood flow
• necorsis

Question 12

What is the colour BROWN indicative of?

Answer 12

• haemosiderin (Hb breakdown product)
• methaemoglobin
• lipofuscin/ceroid
• inflammation
  *But if you mix enough colour together youll get brown

Question 13

What is the colour BLACK indicative of?

Answer 13

• melanin
• anthracosis
• sometimes OLD blood clots

Question 14

What is the TRANSLUCENCY indicative of?

Answer 14

• fluid

Question 15

What needs to be included in a morphological diagnsosis?

Answer 15

• organ/tissue
• severity
• time
• distribution
• process +/- modifiers

*Over Stimulated Tiny Dogs Pee

Eg. Mild, focal, chronic nodular hyperplasia.