Pathology Flashcards
What are the 8 different disease mechanisms?
1- Congenital/Development
2- Inflammation/Injury
3- Infection
4- Vascular Disorders
5- Environmental/Toxic
6- Metabolic
7- Degenerative
8- Tumours (neoplastic + non-neoplastic)
What are some examples of Genetic Congenital Diseases?
CF + Huntingtons + Haemochromatosis + Down Syndrome + Turners Syndrome
What is CF?
- Disorder of cell membrane transport (autosomal recessive abnormality)
- Decreased Chloride secretion + increased sodium and water reabsorption
- Mucus layer dehydration –> Plugging of airways
What are some examples of non-Genetic Congenital Diseases?
- Placental-fetal transmission (most likely to occur when mother infected dfuring pregnancy)
- Eg; Rubella during first trimester –> lead to heart malformations, intellectual disabilities, cataracts, deafness (Rubella during third trimester = decreased effect)
What are the 5 Cardinal Signs of Inflammation?
1- Pain
2- Heat
3- Redness
4- Swelling
5- Loss of function
What are the 3 major components of Acute Inflammation?
1- DILATION - Increased blood flow
2- PERMEABILITY - Plasma proteins + WBC to leave circulation
3- EMIGRATION - Leukocytes to area of damage + be activated to try and remove offending agent.
What is Chemotaxis in relation to the Inflammatory process?
WBC moving through the interstitial space towards target area?
How do WBC destroy invading pathoges?
Phagocytosis in order to engulf the pathogen
Destruction via ‘Reactive Oxygen Species’, Lysosomal Enzymes and Nitric Oxide.
How is inflammation terminated?
1- Inflammatory mediators decrease as pathogen is removed.
2- Neutrophils have short half life -> die from apoptosis a few hrs later
3- Pro-inflammatory cytokines turning into anti-inflammatory cytokines.
What is Serous Inflammation?
Pattern of Acute Inflammation
- Accumulation of clear, protein-poor fluid in tissues and body cavities.
- Blisters from burns
What is Purulent (Suppurative) inflammation + Abscess?
Pattern of Acute Inflammation
- Presence of pus, composed of neutrophils, liquefactive necrosis and oedema
- Pneumonia, Acute Appendicitis
What is Fibrinous Inflammation?
Pattern of Acute Inflammation
- Associated with deposition of fibrin, usually seen in lining of body cavities such option peritoneum and pericardium
- Viral Pericarditis
What is Ulceration?
Pattern of Acute Inflammation
- Local defect/excavation of the surface of an organ/tissue, produced by the sledding of inflamed necrotic tissue.
- Gastric Ulcer from H.pylori
What are some characteristics of Chronic Inflammation?
- Infliltration with MONONUCLEAR CELLS (macrophages, lymphocytes, plasma cells)
- TISSUE DESTRUCTION by persistent agent
- Attempts at HEALING by connective tissue replacement
What is the difference between Hypertrophy and Hyperplasia?
Hypertrophy = Increase in cell size (over stimulation - cardiac/uterine)
Hyperplasia = Increase in number of cells (breast development, liver cell regeneration)
What is Metaplasia?
A reversible change - 1 differentiated cell type is replaced by another cell type.
Eg; 1 cell type sensitive to particular stress = must change
Occurs through reprogramming of local tissues/stem cells or colonisation from adjacent sites.
What may be defected for a Haemorrhagic Disorder to occur?
Defects in vessel walls, platelets or coagulation factors.
What are some cause for Thrombotic Disorders?
- ENDOTHELIAL INJURY - Hypercholesterolemia + Inflammation
- ABNORMAL BLOOD FLOW - Stasis (AFib, Bed rest) + Turbulence (Atherosclerotic, vessel narrowing)
- HYPERCOAGUBILITY - Inherited + acquired diseases
What is Shock?
- State of circulatoryu failure that im[pairs tissue perfusion –> cellular hypoxia
- Cellular injury reversible, however prolonged shock can lead to irreversible tissue injury
