Pathology Flashcards
Define thrombosis
The solidification of blood contents (e.g. platelets & RBC) that forms within the vascular system during life
Give 3 outcomes of a thrombi
Resolution - degrades
Organisation - leaves scar tissue
Embolism - fragment of thrombus break off into circulation
What is an embolus
A mass of material in the vascular system able to become lodged within a vessel and block its lumen
Describe an arterial emboli and give an example of a condition
Lodges in systemic circulation e.g. lodges in carotid artery = Ischaemic stroke
Describe a venous emboli and give an example of a condition
Lodges in pulmonary circulation. E.g. DVT embolises and lodges in pul A = pulmonary embolism
Define ischaemia
Reduction in blood flow to a tissue or part of the body
What is infarction
Tissue death due to inadequate blood supply
What makes an organ susceptible to infarction
If the organ only has a single artery supplying it
3 factors that may cause thrombosis (Virchow’s triad)
Endothelial injury
change in blood flow
increased coagulability
What is atherosclerosis
Accumulation of fibrolipid plaques (atheroma) in the intima of systemic arteries
Narrowing and hardening of arteries
Risk factors of atherosclerosis
Smoking
Hypertension
Diabetes
male
What is apoptosis
Programmed cell death in single cells
What is necrosis
Inflammatory traumatic cell death
What is caseous necrosis
Soft cheese appearance
TB characterised by this form
What is the purpose of apoptosis
Important in normal cell turnover as it prevents cells with accumulated genetic damage from dividing and producing cells which could develop into cancer
What is the basic function of the p53 gene in apoptosis
They detect DNA damage and can then trigger apoptosis
What is the basic principal of how apoptosis occurs
Cascade of activated enzymes ( mainly caspases)
What cells are involved in acute inflammation
Neutrophils and monocytes
Describe the sequence of acute inflammation
- an injury or infection occurs
- neutrophils arrive - they phagocytose and release enzymes
- macrophages arrive and phagocytose them
- outcome: resolution with clearance of inflammation or progression to chronic inflammation
What cells are involved in chronic inflammation
lymphocytes, macrophages, plasma cells
What is a granuloma
an aggregation of macrophages/ histocytes surrounded by lymphocytes that forms in response to chronic inflammation
Stages of acute inflammation response
- vessel gets wider 🡪 increased vessel flow
- Increased vascular permeability 🡪 formation of fluid exudate
- Formation of cellular exudate 🡪 emigration of neutrophil polymorphs
role of fibroblasts in inflammation
produce collagenous connective tissue in scarring
How do lifespans differ between neutrophils, macrophages and lymphocytes
neutrophils have a very short lifespan of 2-3 days
macrophages live months to years
Lymphocytes are live several years
Give an example of acute inflammation
Appendicitis
What does the presence of both granulomas and eosinophils indicate
a parasite
What do all granulomas secrete as a blood marker
ACE
Give 3 examples of conditions which cause granulomas to develop
No central necrosis:
*Leprosy
* Crohn’s disease
Central necrosis:
*Tuberculosis
What are the 2 ways chronic inflammation occurs
Progression from acute inflammation
Starts chronic e.g. infectious mononucleosis
What is hypertrophy
Increase in size of organ due to increase in size of constituent cells
Occurs in organs where cells can’t divide
Give an example of hypertrophy
Skeletal muscles in athletes
What is hyperplasia
Increase in size of organ due to increase in the number of its constituent cells
Give an example of mixed hypertrophy/hyperplasia
Smooth muscle cells of the uterus during pregnancy
What is metaplasia
The change in cell differentiation from one fully-differentiated cell
type to another
What usually causes metaplasia
Consistent change in the environment on an epithelial surface
Give an example of metaplasia
Squamous epithelium of the oesophagus can become columnar
epithelium in response to continued stomach acid reflux (Barrett’s Oesophagus)
What is dysplasia
Morphological changes seen in cells in the progression to becoming cancer
What is carcinogenesis
The transformation of normal cells into neoplastic cells through permanent genetic alterations or mutations
What are carcinogens
Agents known or suspected to cause tumours
Carcinogenic vs oncogenic
Oncogenic are tumour causing agents while carcinogenic are cancer causing agents
Risk factor of lung cancer
Smoking
Risk factor of bladder cancer
Dyes and rubber industry
What drug inhibits platelet aggregation
Aspirin
Reverse smoking increases the incidence of which cancer?
Oral cancer
Which cancer can human papilloma virus cause
Cervical cancer
Which cancer can be caused by excess alcohol consumption
Colon cancer
What are the 5 Cardinal signs of inflammation
Heat (calor)
Redness (rubor; dilation of small vessels )
Tumour (swelling; from oedema/ physical mass )
Pain ( dolor )
Loss of function (functio laesa)
What are the 3 stages of inflammation
- Increased vessel permeability - gets wider which increases flow
- fluid exudate - leaky vessel
- cellular exudate - neutrophils become abundant
State the 4 outcomes of acute inflammation
Resolution
Suppuration
organisation
Progression
What is suppuration in terms of inflammation
- Formation of pus
- This becomes surrounded by a pyogenic membrane
- leads to scarring
What is organisation in terms of inflammation
- replacement by granulation tissue
- New capillaries grow into the inflammatory exudate, macrophages migrate and fibrosis occurs
Describe resolution in terms of inflammatory outcome
Complete restoration of tissues to normal
Minimal cell death and rapid destruction of causal agent
Explain the stages of neutrophil action in acute inflammation
- Margination - migrate to edge of blood vessel
- Adhesion - selectins bind neutrophil, cause rolling along BV
- Emigration - neutrophils pass through endothelial cells
- Diapedesis - RBC may also escape from vessels passively
Clinical features pf arterial thrombi
Loss of pulse
Area becomes cold, pale and painful
Give a condition that arterial thrombus can lead to
stroke
Treatment for arterial thrombi
antiplatelets (aspirin)
Give a condition that venous thrombosis can lead to
deep vein thrombosis
Formation of arterial thrombi
- Endothelial cell damage
- VWF binds to exposed collagen and platelets bind to this - aggregation occurs
- Turbulence in blood flow due to obstruction of lumen
- Fibrin deposition and platelet clumping occurs - RBCs and platelets clump together and are meshed in fibrin
- Positive feedback so process continues indefinitely - thrombus formation
Common cause of venous thrombosis
Lower blood pressure in veins - stasis
This allows for a thrombus to form
Clinical features of venous thrombosis
Tender
Swollen
Red
Treatment for venous thrombosis
anticoagulants (aspirin)
Give 3 factors that can affect endothelial injury
Trauma
Hypertension
Invasive procedures
Give 3 factors that can increase coagulability
sepsis
smoking
malignancy
Constituents of atherosclerotic plaque
lipid
macrophages
Platelets
smooth muscle cells
Formation of an atherosclerotic plaque
- High levels of LDL in the blood accumulate in arterial wall
- Macrophages are attracted to the damage site where they take up lipids to form foam cells
- A fatty streak forms (earliest stage of plaque)
- Foam cells promote smooth muscle cell proliferation around lipid core and formation of a fibrous cap (collagen)
State the 3 pathways of apoptosis
Intrinsic, extrinsic and cytotoxic
What is a neoplasm
A lesion resulting from the autonomous or relatively autonomous abnormal growth of cells which persists after the initiating stimulus is removed
What is a tumour
Any abnormal swelling
Can be caused by inflammation, hypertrophy, neoplasms etc
Describe the structure of neoplasms
Consist of neoplasticism cells with a surrounding stroma
Neoplastic cells are derived from nucleated cells
What are the 2 methods of neoplasm classification
Behavioural - benign/malignant
Histogenetic - cell of origin
Common features of benign neoplasms
- Localised & non-invasive
- Slow growth rate
- Low mitosis activity
- Close resemblance to normal tissue
- Normally encapsulated/ circumscribed
- Necrosis and ulceration is rare as they don’t tend to outgrow blood supply
- Often exophytic ( grows outwards )
Common features of malignant neoplasms
- Invasive
- Endophytic growth (inwards)
- Metastases
- Rapid growth rate - high mitosis activities
- Necrosis and ulceration is common
- Variable resemblance to normal tissue
- Poorly circumscribed
What is the defining feature of a malignant neoplasm
Invasive
What does the term ‘high grade neoplasm’ mean
Low resemblance to normal tissue which means a poorer prognosis is likely
Give 3 ways benign neoplasms cause morbidity and mortality
Pressure on adjacent structures
Transformation to malignant neoplasms
Obstruct flow
What are the 3 different origins of a neoplasm
Epithelial cells
Connective tissue
Lymphoid/ haematopoietic organs
state the suffix of all neoplasms
-oma
What is the name of a benign tumour of non-glandular/ non- secretory epithelium
Papilloma
What is name for a benign tumour of glandular/ secretory epithelium
Adenoma
What is the name for a malignant epithelial neoplasm
Carcinoma
What is the name for a malignant tumour of glandular epithelium
Adenocarcinomas
Give the name for benign connective tissue neoplasms of the following: Adipocytes, cartilage, bone, vascular
Adipocytes - Lipoma
Cartilage - Chondroma
Bone - Osteoma
Vascular - Angioma
Give the name for benign connective tissue neoplasms of the following: striated muscle, smooth muscle and nerves
Striated muscle - Rhabdomyoma
Smooth muscle - leimyoma
Nerves - neuroma
Suffix of malignant connective tissue neoplasms
‘Sarcoma’
What is the name for a malignant CT neoplasm of striated muscle
Rhabdomyosarcoma
What is a malignant neoplasm known as when the cell of origin is unknown
Anaplastic
Give 3 examples of ‘-omas’ that aren’t neoplasms
Granuloma
Mycetoma
Tuberculoma
What is the name for a malignant neoplasm of lymphoid cells
Lymphoma
Which tumour metastasise to bone ( BLT KP )
Breast
Lungs
Thyroid
Kidney
Prostate
Which 3 cancers are screened for in the UK
Bowel
Breast
Cervical
Describe the process of metastasis
- Tumour cells detach from their neighbours
- Invasion of surrounding connective tissue
- Intravasation into lumen of vessels
- Evasion of host immune defence
- Adherence to endothelium at a remote location
- Extravasation of the cells from the vessel lumen into the surrounding tissue
- Tumour cells proliferate in the new environment
Give 3 ways in which tumour cells evade host immune defence
- aggregation with platelets
- shedding of surface antigens
- adhesion to other tumour cells
Briefly describe TNM staging of for tumours
T - refers to primary tumour
N – Refers to lymph node status
M – Refers to metastatic status
Give 3 factors that can cause reduced blood flow
Immobility
Atrial fibrillation
Varicose (swollen) veins
Define atrophy
The decrease in the size of an organ or cell be reduction in cell size and/or number
