Background Flashcards
1
Q
Pancreatic cancer background
A
Epidemiology
- disease of older age
- > over 65
Aetiology
- Environment risk factors
- > smoking
- Genetic
- > family hx
- > hereditary pancreatitis
- > peutz jeghers
- > BRCA
- > familial atypical multiple mole melanoma syndrome (p16)
- > hereditary non-polyposis CCS (Lynch)
Pathophys
- Site
- > majority head
- > decreases towards tail
- Precursor
- > pancreatic intraepithelial neoplasia (1-3 differentiation)
- Types
- > vast majority are exocrine = ductal adenocarcinoma
- > rarely endocrine = neuroendocrine
- Ductal adenocarcinoma subtypes
- > tubular (most common)
- > adenosquamous
- > colloid (mucinous/non cystic)
- > hepatoid
- > medullary
- > signet ring
- > undifferentiated
- Spread
- > lymphatic spread in majority
- > vascular/perineural invasion
- > mets to lung/liver/brain/skin
2
Q
Bowel obstruction background
A
Epidemiology
- small more common than large
- small
- > under 5% lifetime risk virgin abdo
- > over 50% post surgery
Aetiology
- small
- > extrinsic = adhesions/hernias/volvulus
- > intrinsic = stricture/neoplasia/haematoma
- > luminal = gall stone/foreign body/intussusception
- large
- > neoplasia
- > volvulus (sigmoid/caecal)
- > stricture
- pseudo-obstruction
- > hypomagnesaemia/hypercalcaemia
- > hypothyroid
- > CCB/anti-depressants/opioids
- > major surgery/severe illness/trauma
- > parkinsons/MS/hirschprungs
Pathophys
- proximal dilation
- distal hyper-peristalsis and clearance
- venous congestion
- > increased pressure/decreased arterial supply
- > ischaemia and infarction
- pseudo-obstruction
- > interruption of ANS supply
- > functional obstruction
- > most commonly caecum/ascending colon
3
Q
Prostate cancer background
A
Epidemiology
- 2nd most common cancer in aus men
- 2nd most common cause of cancer death in aus men
Aetiology
- Risk factors
- > family hx (young age/BRAC/mortality)
- > obesity
- > high fat diet
Pathophys
- Spread
- > direct = bladder/seminal glands/peri-prostatic tissue
- > lymphatics = para-aortic
- > haematogenous = bone/lung/liver/pleura/adrenals
- Staging
- > primary tumour (clinical/pathological)
- > lymph node involvement
- > PSA
- > Gleeson group
4
Q
BPH background
A
Epidemiology
- approx 50% at 50 years
- approx 80% at 80 years
Aetiology
- Increased testosterone:oestrogen
- Risk factors
- > family hx
- > smoking
- > metabolic syndrome
Pathophys
- hyperplasia of epithelium/stroma
- > increased stroma:epithelium
- mostly in transitional zone
- obstruction
- > increased epithelial tissue
- > stromal smooth muscle tone
5
Q
Impotence background
A
Epidemiology
-almost 20% of adults
Aetiology
- Atherosclerosis (most common)
- > HTN/dyslipidaemia
- Diabetes
- > atherosclerotic/neurogenic/endothelial dysfunction
- Medications
- > anti-depressants
- > anti-psychotics
- > beta blockers
- Iatrogenic
- > pelvic surgery
- > radiation
- Neurogenic
- > stroke
- > MS
- > Alzheimers
- > Parkinsons
- Endocrine
- > hypogonadism
- > thyroid dysfunction
- > hyperprolactimaemia
Pathophys
- Impairment of normal processes
- > cavernosal smooth muscle relaxation
- > increased sinusoidal blood flow
- > venous occlusion
6
Q
Septic arthritis background
A
epidemiology
- most common in before school age
- risk factors for adults
- > advanced age
- > pre-existing arthropathy
- > immunosuppression
- > IV drug use
- risk factors for children
- > younger age
- > prematurity
- > cannulisation
aetiology
- adults
- > staph aureus (most common)
- > strep species (healthy adults)
- > gram negative rods (GIT infection/immunocomp)
- children
- > staph aureus (most common)
- > strep species (GBS=neonates/pneumococcal=toddler/GAS=older kids)
- > kingella (toddlers)
- > neisseria (disseminated in newborn/sexual active)
- > haemophilus in unvaccinated
pathophys
- route
- > haematogenous most common
- > direct inoculation with trauma
- > contiguous spread with osteomyelitis (kids)
- synovium
- > highly vascular
- > no basement membrane
7
Q
ddx swollen testicle
A
Touching His Swollen Testicles Excites Her Hairy Vagina Excited
- Torsion
- Hernia
- Spermatocele (epididymal cyst)
- Tumour
- Epididymitis/epididymo-orchitis
- Haematoma/haematocele
- Hydrocele
- Varicocele
8
Q
Background epididymitis
A
Epidemiology
-most common cause of acute scrotal pain
Aetiology
- Sexually transmitted infection
- > chlamydia
- > gonorrhoea
- > mycoplasma genitalium
- > e coli (if insertive anal sex)
- Abnormal anatomy/instrumentation/immunosuppression
- > e coli
- > proteus
- > candida
- Non bacterial
- > mumps
- > HSP
- > bechets
Pathophys
- Infective
- > ascent from urethral infection (via ejaculatory ducts/vas)
- > may involve testicle (epididymo-orchitis)
- Non infective
- > vasculitic process in bechet/HSP
9
Q
Peptic ulcer background
A
Epidemiology
-peaks after 5th decade
Aetiology
- H pylori infection
- NSAIDs
- adenocarcinoma
- Rarer
- > stress ulcer
- > Zollinger Ellison
- > bisphosphonates
- > crohns
- > CMV in HIV
Pathophys
- Duodenal h pylori ulcer
- > antral predominant h pylori infection
- > reduced somatostatin produced
- > gastric acid hypersecretion
- Gastric h pylori ulcer
- > widespread h pylori infection
- > reduced or normal gastric acid secretion
- NSAIDs
- > direct effect with ion trapping
- > indirect with COX1 inhibition
- > bleeding risk with anti-platelet action
- Complications
- > bleeding
- > penetration
- > perforation
- > gastric outlet obstruction
- Gastric adenocarcinoma
- > antral then diffuse atrophic gastritis
- > intestinal metaplasia
- > neoplasia
- MALT lymphoma
- > T and B cell aggregation/activation in lamina propria
- > forms follicle similar to Peyers patch
- > aberrant activation -> neoplasia
10
Q
Carotid artery stenosis background
A
Epidemiology
- asymptomatic stenosis
- > just under 10% of women >70
- > just over 10% of men >70
Aetiology
- Vast majority
- > atherosclerosis at carotid bifurcation
- Rarely
- > fibromuscular dysplasia
- > dissection/haematoma
- > radiation arteritis
Pathophys
- Ischaemic stroke
- > associated with carotid stenosis in up to 15%
- > usually plaque rupture with thrombosis/embolism
- > rarely due to progressive plaque expansion
- Embolism
- > intracranial arteries = TIA/stroke
- > retinal arteries = amorous fugax/retinal stroke
- Classification
- > symptomatic/asymptomatic
- > mild (<50% stenosis)
- > moderate (50-69% stenosis)
- > severe (>70%)
- > near occlusion/occlusion
11
Q
ddx leg ulcer
A
venous arterial neuropathic physical ->thermal ->pressure ->chemical infection ->staph/strep vasculitis ->small = SLE/RA/drug induced/cryoglobinaemia ->medium = polyarteritis nodosa ->small/medium = ANCA associated drugs -warfarin -heparin
12
Q
Chronic venous insufficiency background
A
Epidemiology
- CVI = between 5-10%
- > venous ulcers = 1-2%
- varicose veins
- > 40% at 60 years
Aetiology
- CVI
- > reflux is most common
- > post obstructive
- > rarely congenital absence of valves
- Varicose veins
- > genetic
- > post thrombotic
Classification (CEAP)
- Clinical
- > no signs
- > telangiectasia/reticular veins
- > varicose veins (>3mm diameter)
- > oedema
- > pigmentation/eczema
- > atrophia blanche/lipdermatosclerosis
- > healed vs active
- > symptomatic vs asymptomatic
- Etiology
- > congenital
- > primary
- > secondary
- Anatomy
- > superficial
- > deep
- > perforator
- Pathophysiology
- > reflux
- > obstruction
- > mixed
13
Q
PAD background
A
Epidemiology
- Increases with age
- > 1% in 40’s
- > 20% in 80’s
- Normal cardiovascular risk factors
Claudication aetiology
- Atherosclerosis
- > almost always
- Rare causes
- > coarctation of aorta
- > fibromuscular dysplasia
- > dissection/aneurysm
- > vasospasm
- > vasculitis
- > popliteal artery entrapment
Classification
- Asymptomatic
- Claudication
- > inadequate blood flow during exercise
- Critical limb ischaemia
- > compromise of blood flow to extremity
- > rest pain/ulcers/gangrene
- Acute limb ischaemia
- > sudden decrease in limb perfusion
- > threatens viability
- > 6 P’s
14
Q
Cellulitis background
A
Epidemiology
- risk factors
- > prior episodes
- > ulcer/wound
- > dermatosis
- > tinea
- > lymphoedema/venous insufficiency
Aeiology
- Common
- > GAS
- > s aureus
- Immunocompromise
- > pseudomonas
- > cryptococcus
Pathophys
- Micro-organisms gain access to dermal/sub cut tissue
- > disruption of cutaneous barrier
- Complications
- > sepsis
- > chronic limb oedema (damage to lymphatics)
15
Q
Necrotising Fasciitis background
A
Epidemiology
-Type 1 more common than Type 2
Aetiology
- Puncture wounds
- Surgery
- Trauma (varicella/IVD)
- Idiopathic
Pathophys
- Type 1
- > polymicrobial
- > anaerobe (bacterioides)
- > facultative anaerobe (e coli/pseudomonas/klebsiella)
- > with or without staph aureus
- Type 2
- > monomicrobial
- > most common = GAS
- > MRSA
- Fourniers
- > Nec fasc of perineum/scrotum
