Pathology Flashcards
Two types of bone tumours? (in their features)
Lytic (most common) bone broken down
Sclerotic - hardens bone
Main presenting features of bone tumours?
Swelling Pain Pathological fracture Hyper-calcemia Fever
What is osteochondroma?
Common benign growth of epiphyses
Types of bone marrow tumours?
Leukaemia
Multiple Myeloma
3 most common types of dementia?
Alzheimers
Dementia with lewy bodies
Multiple Infarct dementia
Name of acute and reversible cognitive dysfunction
delirium
Definition of dementia?
Irreversible decline of cognitive function from an individual that was previously of normal intellectual abilities
Histological changes in alzheimers
AB amyloid plaques
Angiopathy due to AB amyloid
Neurofibrillary tangles of Tau
Loss of neurones
What stain is used to demonstrate amyloid?
Congo red
What are the two proteins that have roles in the pathogenesis of dementia?
What do they do?
APP:
Forms Amyloid Beta when it is not degraded properly
This produces angiopathy and senile plaques
Tau:
Amyloid beta causes it to be hyperpolarised this leads to neurofibrillary tangles of Tau and then neuronal death
Discriminative features of lewy body dementia?
Fluctuations in mental state
Visual hallucinations
Features of parkinsons
What are lewy bodies?
Aggregates of α-synuclein
Risk factors for multi-infarct dementia?
General vascular risks:
Hyperlipidaemia
High Blood Pressure
Smoking
Diabetes
What are the spongiform transmissible encephalopathies?
Transmissible forms of rapidly progressive dementia, due to changes in protein structure, (prion proteins)
What are the pathological changes that lead to spongiform ecephalopathy in prion proteins?
PrPc is the normal form of the protein, this can spontaneously change or be transmitted at PrPsc, PrPsc causes PrPc to change to PrPsc, producing a positive feedback loop, accumulating PrPsc in the CNS and causing rapid neurodegeneration.
What are common effects of rheumatoid arthritis?
Proximal metacarpal joints inflamed
Ulnar deviation
Can rheumatoid arthritis predispose to osteoarthritis
Yes
Pathogenesis leading to rheumatoid arthritis?
Initial inflammation due to an infection, IgG antibodies released
Body makes anti-idiotype antibodies (antibodies against the IgG antibodies)
How is complement activated?
Activated by the Fc portion of the antibody when it is bound to it’s antigen
What is rheumatoid factor?
The anti-idiotype antibodies that can be tested for
Where else can immune complex deposition in rheumatoid disease?
Lungs - Fibrosis
Blood vessels - vasculitis
Heart - myocarditis
Skin - rheumatoid nodules
Whats a granuloma?
Collection of macrophages
Why is the SAA protein increased in rheumatoid arthritis patients?
What can it lead to formation of?
It’s concentration is increased as it is produced in the liver as an acute phase protein, and it its production is increased in reaction to circulating cytokines
Can lead to the formation of amyloid
Three main types of stroke?
Cerebral infarction (85%)
Intracerebral haemorrhage
Subarachnoid haemorrhage
Two mechanisms of cerebral infarction?
Embolic
Thrombotic
3 common causes of thrombus formation in the heart?
Atrial Fibrillation
Following an MI
cardiac valve vegetation due to endocarditis
2 Gross neuroanatomical changes in alzheimers disease?
Enlargement of the lateral ventricles
Enlarged Sulci in temporal region - associated with memory
Drugs used in alzheimers disease?
Donzepil - AchEI
Memantine - NMDA receptor antagonists
genes associated with alzheimers?
Early onset: APP, presinilin 1 and 2
Late onset: APOE
What CN does not have a nucleus in the brainstem?
Olfactory
Main difference in Nephrotic and Nephritic syndrome?
Nephrotic: Protein
Nephritic: Blood
What are the pathological changes (grossly) to the brain followoing stroke?
Infarction leads to death of all cells in the necrotic core
3-5 days after macrophages clear debris
1month - 5yrs the debris is removed and a liquid filled cysts remains (liquefactive necrosis0
Causes of death due to stroke?
Immediate infarction of the brainstem
A few days later due to raised ICP or consequences of immobility (bronchopneumonia)
What are watershed infarcts/strokes?
When there is ischaemia due to a systemic decrease in cerebral perfusion e.g. shock, this means the areas that are supplied by two cerebral arteries are at risk and bordering areas between two territories often infarct.
Three main types of stroke?
Ischaemic
Parenchymal Haemorrhage
Subarachnoid Haemorrhage
What type of stroke follows the rupture of a berry aneurysm?
Subarachnoid
What is a berry aneurysm?
Saccular aneurysm of one of the main arteries of the circle of willis or one of it’s branches
What disease predisposes particularly to saccular cerebral arteries?
Autosomal dominant polycystic kidney disease
Methods to prevent re-bleeding in survivors of a saccular aneurysm rupture?
Insertion of metal coil into aneurysm to induce thrombosis
Clipping the neck of the aneurysm
Common route of CNS infection?
Haematogenous
Problems that survivors of meningitis have?
Adhesions in subarachnoid space
Epilepsy
Nerve palsy
Complications associated with adhesions in the subarachnoid space?
Obstructive hydrocephalus
Definition of abscess?
Collection of pus in tissue
Three ways that TB can affect the brain?
Tuberculous meningitis, Tuberculous abscess and spinal osteomyelitis
What is potts disease?
Infection of the vertebral column by TB followed by collapse of vertebrae associated with the inflammation, resulting in compression of the spinal cord
Process of osteoarthritis?
The hyaline cartilage splits and softens, could be due to many things e.g. infection, damage or just wear and tear.
The hyaline cartilage is worn down exposing bone and resulting in inflammation when the bone rubs on the opposing surface
An effusion may form and the joint may be very swollen
What is an effusion?
The Excess amount of synovial fluid in inflamed joints
