Pathology Flashcards
What is Trotter’s triad?
Diagnosis of Nasopharyngeal carcinoma
- Unilateral conductive hearing loss
- Ipsilateral facial and ear pain
- Ipsilateral paralysis of soft palate
Association with EBV infection
What is the effect on APTT, PT and bleeding time in von Willebrands disease?
APTT: Increased
PT: Normal
Bleeding time: Increased
What is Lynch syndrome?
Characterised by aggressive right sided colonic malignancy and Endometrial cancer
Caused by microsatellite instability of DNA repair genes
What are the cell cycle phases and what happens in each phase?
G1: Cell grows, normal functioning
S: Chromosomes are duplicated
G2: cell checks the duplicates for errors preparing for cell division
Mitosis
At what part of the cell cycle does p53 (tumour suppressor gene) act on?
Inhibits progression to S phase from G1
What occurs in a Type 1 hypersensitivity reaction and which Ig is mediated by?
Occurs due to MAST CELL degranulation
Mediated by IgE
E.g. anaphylaxis, asthma
What occurs during a Type 2 hypersensitivity reaction and what Ig is it mediated by?
Due to Ab directed towards antigens on surface of cells (e.g. transfusion reactions, autoimmune haemolytic anaemia)
Mediated by IgG
What occurs in a Type 3 hypersensitivity reaction and what Ig is it mediated by?
Due to formation of immune complexes (e.g. SLE, glomerulonephritis)
Mediated by IgG
What is a type 4 hypersensitivity?
Delayed reaction mediated by T-lymphocytes
Takes 48-72hrs to see effects (e.g. contact dermatitis, Graft vs host disease)
What occurs in a Type 5 hypersensitivity reaction?
Due to AUTO-ANTIBODIES in autoimmune conditions
E.g. Graves’ disease, Myasthenia gravis etc
How does a Hyperacute transplant rejection present and why?
Presents within MINUTES with widespread thrombosis of graft vessels - Graft MUST be removed
Due to host Ab binding to antigens on donor cells (Type 2 hypersensitivity)
What is an Acute Transplant rejection and its underlying pathogenesis, and how is it treated?
Occurs in weeks to months
T cells (CD8) and lymphocyte infiltration
Treated with high dose steroids and immunosuppression
What are the most common HLA found on WBCs in organ rejection?
HLA A, B, DR
What type of hypersensitivity reaction is Acute haemolytic transfusion reaction and how does it present?
Type 2 hypersensitivity
PC: Fever, Hypotension, Tachycardia and Tachypneoa, jaundice, Pain presents within an hour
What are the 2 main types of Lung cancer and their sub types?
Non-small cell lung ca
- Adenocarcinoma
- SCC
- Large cell
Small cell lung lung ca
What are features of small cell lung ca and what population is it strongly associated with?
Cells with near-endocrine differentiation (secrete neuroendocrine hormones)
Typically arise centrally affecting the larger airways (bronchi). Metastasis early on.
Strongly associated with SMOKERS
Chemosensitive but rarely results in long lasting remission
What type of lung ca has the best prognosis?
SCC (NSCLC)
What is the most common lung ca?
Adenocarcinoma
What is the most common lung ca in smokers?
SCC (NSCLC)
What lung ca is commonly associated with hypercalcaemia and Pancoast syndrome?
SCC (NSCLC)
What is neoplasia?
Similar hyperplasia but is abnormal multiplication and starting to lose normal shape
What is dysplasia and what can this be in response to?
Change in the normal shape, size and organisation
Usually a response to Chronic irritation or inflammation (i.e smoking or inflammation)
What is metaplasia?
Change in cell type. Changes can be reversible at this stage if stimulus is removed, otherwise it progress to anaplasia
High risk for malignancy
What is anaplsia?
Reversal in differentiation of cell OR loss of structural & functional differentiation
Characteristic of cancerous tumours
What 4 changes in cells are seen in anaplasia?
- Loss of polarity
- Pleomorphism (variation in size and shape - often bigger)
- Nucleas:Cytoplasmic ratio (nuclei disproportionately enlarged to cell size)
- Anisonucleosis (variation in size + shape of nuclei)
What is the distribution of dystrophic calcification and what conditions can it be associated with?
Tends to be localised in abnormal (DISEASED) tissue (e.g. calcific aortic stenosis
Associated with TB, Chronic abscesses, Infarcts, Thrombi, CMV, Atherosclerosis
Normal serum calcium
What type of fibril protein is deposited in inflammatory conditions?
Serum Amyloid A (AA) - Secondary amyloidosis
Associated with chronic inflammatory disorders (e.g RA, IBD etc.)
What protein type is associated with Primary Amyloidsis and what conditions are they associated with?
Protein - AL (from Ig light chains)
Seen in plasma cell disorders (e.g. Multiple Myeloma)
What type of protein is seen in patients with amyloidosis secondary to ESRD or dialysis?
B2-microglobulin
What is ALP a tumour marker for?
- Bone + liver mets
- Pagets disease
- Seminoma
What is AFP a tumour marker for?
Hepatocellular ca.
Teratoma
What tumour marker can be elevated in Choriocarcinomas?
hCG
What are the tumour markers for Breast ca?
Ca 15-3
Ca 27-29
CEA (minor association)
What is the tumour marker for pancreatic adenocarcinomas?
Ca 19-9
A raised CA 125 is seen what type of cancer?
Ovarian ca
What is calcitonin a specific tumour marker for?
Medullary thyroid ca
What cancers are associated with EBV?
- Burkitts lymphoma
- Hodgkins lymphoma
- Nasopharyngeal ca
Cervical, anal and penile ca are associated with which virus?
HPV 16/18
Which oncogene is associated with retinoblastomas?
RbI
What condition is the P53 oncogene associated with?
LiFraumeni
What is acute intermittent porphyria and how does it present?
6 Ps
- Porphobillinogen deaminase deficiency
- Pain in abdo (most common)
- Psychological symptoms (anxiety, depression, hallucination etc.)
- Peripheral neuropathy
- Pee abnormality (dysuria, incontinence/retention)
- Precipitated by drugs (e.g. barbiturates, oral contraceptives)
What subtype of cell is most often associated with popcorn cells seen in Hodgkin’s lymphoma?
They are the lymphohistiocytic (L-H) variant of Reed Sternberg cells and are associated with nodular lymphocyte predominant Hodgkin lymphoma
What is Kwashiorkor?
Protein malnutrition resulting in skin lesions and oedema (low oncotic pressure), liver malfunction (fattu change due to low apolipoprotein synthesis)
MEALS:
- malnutrition
- edema
- anaemia
- Liver (fatty)
- Skin lesions
PC: small child with swollen abdomen
What is the shelf life of whole blood and RBC if stored appropriately?
35 days
What is the shelf life of platelets and at what temperature should they be stored?
5 DAYS
20-24 degrees celsius
When type of murmur is seen in pulmonary or aortic stenosis?
Systolic murmur
When is a murmur heard in pulmonary or aortic regurgitation?
Early Diastole
What causes a mid-diastolic to late diastolic murmur?
Mitral stenosis
Tricuspid stenosis
What is the most diagnostic histological factor of acute inflammation?
Neutrophil polymorphs
What is a granuloma?
Consists of microscopic aggregation of macrophages
What happens in Type A gastritis?
Autoimmune
Abs to parietal cells causing reduction in cells = loss of intrinsic factor = B12 malabsorption = megaloblastic anaemia
Causes elevated gastrin levels
What kind of gastritis is associated with H.pylori infection?
Type B - Antral gastritis
Intestinal metaplasia may occur and will require surveillance endoscopy
What type of ulcer is Curling’s ulcer and what is the pathophysiology?
It is a Stress ulcer
Caused by mucosal ischaemia during hypotension/hypovolaemia (e.g. burns)
What is Menetriers disease?
Gross hypertrophy of gastric mucosal folds with excessive mucous production
Pre-malignant condition. Associated with gastric ca
In a patient with abdominal pain with neurological signs, what main 2 diagnosis need to be excluded first?
Acute intermittent porphyria OR Lead poisoning until proven otherwise
What are features of lead poisoning?
- Abdo pain
- Peripheral neuropathy
- Fatigue
- Blue lines on gum margins (20%)
- Constipation
How is lead poisoning managed?
- DMSA
- D-penicillamine
- Dimercaprol
What happens in gangrene?
Necrosis with putrefaction of tissue
Hb degenerates and results I’m deposition of iron sulphide (hence the black colour)
What is the most common type of necrosis?
Coagulative necrosis
Early stages, histological appearances may demonstrate little change. Later stages, cellular outlines are seen with loss of intracellular detail
What are the causes of DIC?
DISSEMINATED
Dx: D-dimer
Immune complexes
Snakebite, shock, heatstroke
SLE
Eclampsia, HELLP syndrome
Massive tissue damage
Infections
Neoplasms
Acute promyelocytic leukaemia
Tumour products (TF etc.)
Endotoxins (bacterial)
Dead fetus (retained)
What are the most common blood test findings in DIC?
Prolonged clotting times
Thrombocytopenia
Decreased fibrinogen
How is DIC managed?
Platelets
Fibrinogen
Cryoprecipitate
Treat underlying condition
What is neuropaxia and what is the usual prognosis?
Condition where the nerve is intact but electrical condition is affected
Full recovery expected, autonomic function is preserved and Wallerian degeneration does not occur
What is it called when an axon is damaged but the myelin sheath is preserved?
Axonotmesis
What is Wallerian degeneration?
Axonal degeneration distal to site of the injury, typically occurring 24-36hrs following the injury
Myelin sheath degenerates and is phagocytose by tissue macrophages
Which gene mutation is associated with absence of the vas deferens?
Cystic fibrosis CFTR gene mutations (40%)
Some non CF cases are due to unilateral renal agenesis
What is choanal atresia?
Congenital disorder causing posterior nasal airway occlusion by soft tissue or bone
Can be uni-/bi lateral
Rx: fenestration procedures to restore patency
What is the inheritance pattern of Achondroplasia?
Autosomal dominant
Cause of dwarfism due to defects in fibroblast GF receptor
What are radiological features of achondroplasia?
- Large skull with narrow foramen magnum
- Short flattened vertebral bodies
- Narrow spinal canal
- Broad, short metacarpals
What is the pathophysiology of a cleft palate?
Non-fusion of the two palatine shelves
Complete cases are associated with complete separation of the nasal septum and vomer from the palatine processes
What malignancies are associated with Li-Fraumeni syndrome?
Sarcomas and leukemias
Dx when individual develops sarcoma <45yrs OR 1st degrees relative diagnosed with any cancer <45yrs
How is Hodgkins lymphoma staged?
Ann Arbor system
Stage 1: Single lymph node region
Stage 2: 2+ regions on SAME side of diaphragm
Stage 3: Involvement of lymph nodes on BOTH sides of diaphragm
Stage 4: Involvement of extra nodal sites
What type of cell is associated with Hodgkin’s lymphoma?
Reed Sternberg cells
How does hereditary spherocytosis present?
Haemolytic anaemia
Jaundice (hyperbilirubinaemia)
Splenomegaly
What is a pheochromocytoma and how does it present?
Neuroendocrine tumour of chromatin cells of adrenal medulla
HTN, Hyperglycaemia, Sweating, Headache, symptoms similar to panic attack
How is a pheochromocytoma diagnosed?
urine analysis: vanillymandelic acid (VMA)
Serum metanephrine levels
CT/MRI to localise lesion
How is a pheochromocytoma managed?
- Irreversible alpha blocker + beta blocker
- Fluid resuscitation
- Surgical excision
What CT findings of adrenal lesion suggest benign disease?
- <3cm in size
- Lipid rich tissue
- Thin wall to lesion
- Homogenous texture
What is a glucagonoma?
Pancreatic tumour arising from alpha cells of the pancreas
PC: diarrhoea, wt loss, necrolytic migratory erythema, elevated glucagon (>1000)
Requires careful staging prior to surgery as usually malignant and non-resectable
What are Hassall’s corpuscles?
Keratinised centre surrounded by medullary epithelial cells found in the thymus
Which pharyngeal pouches does the thymus develop from?
3rd and 4th pharyngeal pouches
In what age group does Ewing Sarcoma normally present and what is the commonest site to be affected?
Affects 10-20 years old
Located in femoral diaphysis most commonly
What is actinomycosis and what is seen on histology and how is it treated?
Chronic, progressive granulomatous disease caused by gram +ve bacteria (actinomyces).
Histology: sulphur granules + gram +ve organisms
Rx: Long term penicillin therapy +/- surgical resection of extensive necrotic tissue, non-healing sinus tracts
Which polypeptide is present in all collagen types?
Glycine
What are the 4 subtypes of osteogenesis imperfecta with defect of type 1 collagen?
Type 1: collagen is normal quality but insufficient quantity
Type 2: Poor quantity and quality
Type 3: Poorly formed collagen but normal quantity
Type 4: Sufficient quantity but poor quality
What types of collagen are affected in Ehlers Danlos?
Abnormalities of Type 1 and 3 collagens
What are Aschoff-Rokitansky sinuses?
Aschoff-Rokitansky sinuses are the result of hyperplasia and herniation of epithelial cells through the fibromuscular layer of the gallbladder wall.
They may be macroscopic or microscopic. Aschoff-Rokitansky sinuses may be identified in cases of chronic cholecystitis and gallstones
What cells are seen on OGD for diagnosis of Barrett’s oesophagus?
Specialised intestinal metaplasia
Goblet cells
What is the cell of origin of the majority of pancreatic cancers?
Ductular epithelial origin
Over 90% of pancreatic carcinomas are adenocarcinomas
