Background Flashcards
1
Q
ACS background
A
Epidemiology
- NSTEMI more common than STEMI
- > approx 75% of ACS cases
Aetiology
- STEMI
- > complete occlusion
- > usually Type I
- NSTEMI
- > transient or partial occlusion
- > Type I or Type II
- UA
- > coronary artery narrowing
- > usually Type I
Pathophys
- Type 1 MI
- > plaque rupture with thrombus/embolism
- > STEMI or NSTEMI
- Type 2 MI
- > oxygen supply/demand imbalance
- > haemorrhage/shock/severe anaemia/arrhythmias/spasm/dissection
- > most commonly NSTEMI
2
Q
DVT background
A
Epidemiology
- incidence increases exponentially with age
- 0.5% per year by 85yrs
Aetiology
- Virchows triad
- > vessel injury
- > venous stasis
- > activation of clotting system
- Provoked
- > neoplasia
- > trauma
- > immobility
- > surgery
- > air travel
- > hormonal therapy
- > pregnancy
- Unprovoked
- > factor V leiden
- > prothrombin gene mutation
Pathophys
- Natural history
- > clot usually forms just above/below valve
- > propagates proximally
- > completely or partially occludes lumen
- > continually broken down releasing D dimer
- Superficial vs deep
- > superficial = superficial thrombophlebitis
- > superficial = low risk (unless proximal great saphenous)
- > deep = posterior or anterior tibial/perineal/penetrators
- Proximal vs distal
- > popliteal and up is proximal
- > proximal = higher risk
3
Q
Thrombocytopaenia background
A
Epidemiology of ITP
- Incidence
- > less than 1/1,000
- Age
- > more common in adults
- > acute = children
- > chronic = women of reproductive age
Aetiology (PHD MINICAB)
- Pregnancy
- > gestational
- > pre-eclampsia/HELLP
- Hepatic
- > low TPO
- > splenic congestion
- Drugs
- > antibiotics
- > anticonvulsants
- > heparins
- Microangiopathic haemolytic anaemias
- > TTP
- > HUS
- Immune thrombocytopaenia
- Nutritional deficiency
- > folate
- > B 12
- Infection
- > viral (mumps/rubella/varicella/hep B/EBV/parvo)
- > bacterial sepsis (DIC/bone marrow/direct destruction)
- Congenital
- > Bernard soulier
- Autoimmune
- > SLE (secondary ITP)
- > antiphospholipid
- > rheumatoid (felty)
- Bone marrow
- > leukaemia
- > aplastic anaemia
- > myelodysplastic syndrome
- > myelofibrosis
Pathophys ITP
- spleen produces antibodies
- > directed at GpIIb/IIIa
- > marked for splenic destruction
- may also underproduce platelets
- primary
- > more common
- > cause unknonw
- secondary
- > following viral infection/autoimmune disease
4
Q
Dialysis peritonitis background
A
Epidemiology
-almost 50% incidence in first year
Aetiology
- Bacterial (vast majority)
- > gram positive more common than negative
- > s aureus/s epidermidis/strep species/enterococci
- > e coli/klebsiela/pseudomonas
- Fungal
- > candida species
Pathophys
- most commonly intraluminal spread
- > poor sterile technique (connecting 4x daily)
- peri-luminal
- > extension from exit site
- transvisceral
- > migration from bowel
- rarely haematogenous
Outcome
- mortality
- > approx 5%
- removal of catheter
- > almost 1/4
- switch to haemo
- > almost 1/4
5
Q
Type II diabetes background
A
Epidemiology
- diabetes
- > lifetime prevalence = almost 5%
- type II
- > approx 90% of cases
Aetiology
- Genetic risk
- > family hx
- Environmental risk
- > ageing
- > high BMI
- > physical inactivity
- > CVD/HTN
- > PCOS/gestational
Pathophys
- Microvascular
- > nephrology
- > retinopathy
- > neuropathy
- Macrovascular
- > CAD
- > PAD
- > CVD
- Non Vascular (FUDGIE)
- > foot (amputation/ulceration/claw/hammer toes/charcot)
- > urological (cystopathy/UTIs/sexual dysfunction/retrograde ejaculation)
- dermatological (xerosis/pruitis/poor healing/bullosis diabeticorum/diabetic dermopathy)
- gastrointestinal (gastroparesis/diarrhoea/constipation)
- infection (all infections/skin/pulmonary/fungal)
- eye (glaucoma/cataracts)
6
Q
Ascites ddx
A
Haemoperitoneum
Non-peritoneal causes
- Portal HTN
- > cirrhosis (most common cause)
- > fulminant hepatitis
- > massive liver mets
- > budd chiari syndrome
- > HF/constrictive pericarditis
- Hypoalbuminaemia
- > nephrotic syndrome
- > protein losing enteropathy
- Other
- > ovarian tumours/cancers
- > pancreatitis
- > chylous
Peritoneal causes
- Malignancy
- > peritoneal mesothelioma
- > peritoneal carcinomatosis
- Infection
- > usually from bowel
- > TB
- > chlamydia
- > fungal infections
- Other
- > SLE
7
Q
pleural effusion ddx
A
Exudative (PAINTERS)
- pneumonia
- abscess
- infarct
- neoplasia
- TB
- empyema
- rheumatoid pleurisy
- SLE/sarcoid/scleroderma
Transudative (CHARM)
- CCF/cirrhosis
- hypothyroidism
- albumin
- renal failure
- mets to draining nodes
8
Q
Hypercholesterolaemia
A
Epidemiology
- base rate = approx 15%
- CHD = approx 80%
Aetiology
- Primary
- > familial hypercholesterolaemia
- Secondary (more common)
- > sedentary lifestyle
- > trans/saturated fats
- > obesity
- > CKD
- > diabetes
- > hypothyroidism
- > alcoholism
- > cholestatic liver disease
- Medications
- > thiazides
- > glucocorticoids
- > atypical antipsychotics
Pathophys
- Familial
- > autosomal dominant
- Secondary
- > reduced LDL receptor expression
- > excess VLDL production by liver
9
Q
Statin intolerance
A
Epidemiology
- Strong nocebo effect
- > suspected intolerance = 20-30%
- Risk factors
- > simvastatin/atorvastatin
- > high doses (>40mg = 7 fold increase of myopathy)
- > liver/kidney disease
- > hypothyroidism
- > low vitamin D
- > regular vigorous exercise
- > fibrates/glucocorticoids/calcium channel blockers
Aetiology
- Myalgia
- > approx 10%
- Myopathy
- > 1/10,000 per year
- Rhabdo
- > 1/100,000 per year
10
Q
Statin intolerance ddx
A
Fibromyalgia
-3 months tired, poor sleep, widespread MSK pain/tenderness
Polymyalgia rheumatica
-older age, joint stiffness dominates
Viral myositis
-more common in children , acute onset lasting <6weeks
Neuropathic
-unlikely given distribution
Hypothyroid
Vitamin D deficiency
Psychosomatic
11
Q
Headache ddx
A
Most likely
- Tension
- Migraine
- Medication
- opioids
- barbituates
- Sinusitis
Less likley
- Cluster
- Giant cell arteritis
- TMJ dysfunction
Unlikely
- Space occupying lesion
- Chronic subdural haematoma
- CNS infection
- Low pressure headache
12
Q
Headache background
A
Epidemiology
- most common is tension
- > almost 50% prevalence
- migraine much more likely to cause presentation
- > 95% vs 5%
Aetiology
- Tension
- > stress
- > poor sleep
- > missing meals
- Migraine
- > stress
- > poor sleep
- > strong family hx
- > female
- > high caffeine intake
Pathophys
- Tension
- > probably muscular contraction
- Migraine
- > inflammation of first branch of trigeminal
- > innervates large vessels and meninges
- > causes neuronal hyper-excitability (lowered threshold)
13
Q
Macrocytic anaemia ddx
A
MEGALOBLASTIC
B12 deficiency
- Reduced intake (meat/milk/eggs)
- > vegan
- > alcoholism
- Malabsorption
- > crohns
- > coeliac
- > bacterial overgrowth
- > pernicious anaemia
- Impaired GI breakdown
- > atrophic gastritis
- > GI surgery
Folate deficiency
- Reduced intake (green leafy/citrus fruits/meat)
- > elderly/malnourished
- > alcoholism
- Malabsorption
- > achlorhydria
- > tropical sprue
- > coeliac
- > bacterial overgrowth
- Increased turnover
- > malignancy
- > B12 deficiency driven excretion
- > alcoholism driven excretion
Drugs
- methotrexate
- alkylating agents
- antibiotics
NON MEGALOBLASTIC
- Reticulocytosis
- > haemolytic anaemia
- > post bleed
- Alcohol
- Liver disease
- Hypothyroidism
- Myelodysplastic syndrome
14
Q
Liver mass ddx
A
Benign
- Hepatic haemangioma (most common)
- > aetiology not understood
- > vascular malformation
- Focal nodular hyperplasia
- > hepatocyte hyperplasia surrounding scar
- > following vascular abnormality and hyper perfusion
- Hepatocellular adenoma
- > usually women using oestrogen meds
- Regenerative nodules
- > following liver injury
Malignant
- Hepatocellular carcinoma
- Cholangiocarcinoma
- Metastatic disease
15
Q
Hepatocellular carcinoma background
A
Epidemiology
-6th most common cancer worldwide
Aetiology
- cirrhosis due to any cause
- hep B and C
- family hx
- diabetes
Pathophys
- Dysplastic nodules
- > overall = 80% become cancerous within 5 years
- > high grade = pre-cancerous (1/3rd in 2 years)
- > low grade
16
Q
Back pain ddx
A
FT SADISM
- Fracture
- Tumour
- SI
- > sacroiliits
- > spondyloarthropathy
- Abdo
- > kidney
- > pancreas
- > AAA
- Disc
- > herniation/bulg
- Infection
- > epidural abscess
- > discitis
- Spondylolithesis/spondylolysis
- Musckuloskeletal
17
Q
Background lumbar disc herniation
A
Epidemiology
- peak incidence 4th and 5th decades
- far more males
Aetiology
- 95% involve
- > L4/5
- > L5/S1
- Far laterals (rare)
- > L2-L4
- Protrusion
- > eccentric bulging with intact annulus
- Extrusion
- > herniation through annulus but not detached
- Free fragment
- > herniation no longer attached
Pathophys
- Central
- > axial back pain only
- > rarely cauda equina syndrome
- Posterolateral
- > impinges descending nerve root
- > L4/5 affects L5
- Far lateral
- > impinges exiting nerve root
- > L4/5 affects L4
