Cytology - Inflammation and Haemorrhage Flashcards
Information given needed for inflammation. (8)
- Relevant history? (e.g. prior vaccination/injection, tissue injury, foreign body, etc.)
- Is there only one type of inflammatory cell present, or is the inflammation mixed? Chronicity? Concurrent haemorrhage? (Concurrent = existing)
- Are there any tissue-derived cells present, and what is their appearance?
- Any infectious organisms? Are they relevant to the inflammation, or contaminants/normal flora?
- Is there indication for special stains (e.g. acid-fast stain for mycobacterial organisms?)
- Evidence of foreign body material / non-biological material presence?
- Is there concurrent necrosis?
- Can we rule out underlying neoplasia?
What is neutrophilic inflammation?
•When >85% of nucleated cells are neutrophils.
Causes of neutrophilic inflammation. (3)
- Bacterial infection.
- Trauma.
- Tissue necrosis.
What do non-degenerate (normal) neutrophils look like in the blood?
What do degenerate neutrophils look like? (4)
- Changes in cytoplasm - releasing of chemicals to destroy organisms.
- Cell mem not as visible.
- Nuclei more swollen and pale compared to non-degenerate cell.
- Large proportion = compatible with infectious process, not always true though.
If inflammation occurs without an infectious organism, what is it likely due to?
•Trauma to the joint.
Pyknosis/karyorrhexis of neutrophils - fragmented nucleus of neutrophils; neutrophils undergoing apoptosis (neutrophilic inflammation) - irreversible condensation of nucleus (dense nucleus)
What is macrophagic inflammation?
•When macrophages are predominating.
Causes of macrophage inflammation. (3)
- Foreign body reaction.
- Mycobacterial infection.
- Fungal infection.
Multinucleated/giant macrophages =
•Chronic inflammation.
What is Ziehl-Neelsen used to stain?
•Mycobacteria - will stain red (have outer cell mem + are thicker).
What is eosinophilic inflammation?
•When >10% of total nucleated cells are eosinophils (have granules) (among other inflammatory cells).
Causes of eosinophilic inflammation. (4)
- Hypersensitivity/allergic reactions.
- Parasitic infections.
- (Feline asthma, eosinophilic bronchopneumopathy in dogs).
- Paraneoplastic eosinophilic inflammation (T-cell lymphoma, mast cell tumour).
•Canine eosinophil.
•Feline eosinophil.
•Equine eosinophil.
•Bovine eosinophil.
What is lymphocytic/plasmacytic inflammation?
•When lymphocytes are predominating accompanied by variable numbers of plasma cells.
Causes of lymphocytic/plasmacytic inflammation. (2)
- Injection site reactions.
- Other forms of antigenic stimulation.
What is mixed inflammation? (2)
- When a mixture of inflammatory cells is present.
- One cell type may be predominating (e.g. mixed, predominantly neutrophilic inflammation).
Haemorrhage =
•Blood loss/bleeding.
What must happen during blood sampling? (2)
- Haemorrhage must be differentiated from blood contamination - clinician knows if there was iatrogenic (caused by medical examination/treatment) haemorrhage during sampling.
- True haemorrhage platelets may not be visible as they disintegrate quickly (platelets usually seen in iatrogenic haemorrhage where platelets are preserved).
What happens to platelets in haemorrhage? (4)
- Macrophages appear and start phagocytosing erythrocytes (erythrophagocytosis).
- Haemoglobin breakdown products form within macrophages over time:
- 1). Haemosiderin (dark blue/black).
- 2). Haematoidin (golden rhomboid crystals).
