Dunedin 2019 Flashcards
How many neurons in Horner’s and where do they synapse from and to
Horner’s is a 3 neuron arc
1st order – posterolateral hypothalamus, descend through midbrain and pons, terminate in intermediolateral cell column of the spinal cord at C8-T2 aka ciliospinal centre of Budge
2nd order – originates ciliospinal centre of Budge, exits at T2 and enters cervical sympathetic chain (close proximity to pulmonary apex and subclavian artery), ascend sympathetic chain and synapse in superior cervical ganglion at bifurcation of common carotid artery
3rd order – postganglionic pupillomotor fibres exit superior cervical ganglion and ascend along internal carotid artery
Mifepristone MOA and indication
Glucocorticoid receptor antagonist - blocks the effect of cortisol at flucocorticoid receptor
Used to treat hyperglycaemia in Cushing’s syndrome
Ambrisentan MOA
Endothelin receptor antagonist
Sildenafil MOA
Inhibits PDE-5 in smooth muscle of pulmonary vasculature
Riociguat MOA
Dual mode of action
- Sensitises soluble guanylate cyclase to endogenous NO by stabilising NO-sGC binding
- Directly stimulates sGC independent of NO
Iloprost MOA
Prostacyclin analogue
VRE resistance mechanism
Change in cell wall structure from d-ALA d-ALA to d-ALA d-LAC
Most specific antibody for RA
Anti-CCP 95-98% specificity
RF not specific, but similar sensitivity to anti-CCP
Type II error
Falsely accepting the null hypothesis = false negative
Genetic defect a/w autoimmune polyendocrine syndrome type 1
AIRE
Mutation in which gene a/w IPEX
FOX P3
Reed Sternberd Cell surface immunophenotype
CD15 and CD30 positive
CD45 negative
Ipilimumab MOA
CTLA-4 inhibitor
Antigen in HIT
Platelet factor 4
Levetiracetam MOA
Binds to synaptic vesicle protein SV2A, altering vesicle fusion
Ethosuximide MOA
Diminishes T-type calcium currents in the thalamic neurons
Carbamazepine
Inhibits voltage gated sodium channels
Clobazam MOA
Binds to GABA receptor and facilitate the attachment of GABA to the receptor
Signal two in T-cell activation
Interaction between CD28 and CD80/86 on APC
Edwards syndrome
Trisomy 18 - detectable by karyotype
PBC management
Ursodeoxycholic acid
Uveal melanoma commonly metastasises to which site
Liver
Mechanism of red man syndrome
Vancomycin directly causes mast cell degranulation
What extraintestinal manifestation of IBD is associated with active GI inflammation
Large joint arthritis
Positive predictive value formula
sensitivity x prevalence
[sensitivity x prev] + [(1-spec) x (1xprev)]
Negative predictive value formula
specificity x (1-prevalence)
[(1-sensitivity) x prev] + [spec x (1-prev)]
Unfractionated heparin MOA
Binds to antithrombin III -> enhanced ability to inhibit factor Xa and IIa
Also inactivates thrombin and other proteases
Ticagrelor side effects
Resp: dyspnoea
CVS: ventricular pause on ECG, presyncope, syncope
CNS: dizziness, LOC
GI: nausea
Haem: haemorrhage - major and minor
Renal: increased serum Cr (transient)
Liddle’s syndrome
Dysregulation of epithelial ENaC channels in renal collecting ducts
PML treatment
IV hydrocortisone
Stop offending drug
What size adrenal incidentaloma would require adrenalectomy
>=4cm
Next step in management in adrenal incidentaloma <4cm
Hormonal testing - PAC/PRA; plasma-free metanephrines and normetanephrines; overnight 1mg dexamethasone suppression test
If hormonally active then adrenalectomy
Precautions for VZV pneumonitis
Negative pressure isolation for disseminated zoster
Negative pressure isolation for immunocompromised pt with dermatomal zoster
A-a gradient
PAO2 - PaO2
PAO2 = FiO2 (Patm - PH2O) - PCO2/0.8
Standard Mx for ARDS
Low tidal volume ventilation and PEEP
MGUS Dx
Monoclonal protein spike <3g/dL
Plasma cells <10% of bone marrow
No CRAB features
Smouldering MM diagnosis
Monoclonal protein spike >3g/dL
PC >10% of bone marrow
No CRAB features
Multiple myeloma diagnosis
Monoclonal spike
PC >10% or plasmacytoma
CRAB features
Or PC >60% or SFLC >100
Or more than one focal lesion on MRI
PR3-ANCA association
GPA (in 80-90% of cases)
How does fluconazole affect metabolism of some other drugs
Inhibits CYP450
Multiple cystic changes through bilateral lung fields
LAM
- Associated with tuberous sclerosis
Creutzfeldt-Jakob disease
Rapid onset dementia over months
Behavioural change, myoclonus
EEG - generalised periodic sharp wave pattern
MRI - cortical ribboning, caudate and putamen T2 hyperintensity and diffusion restriction on DWI/ADC
Difference between NMS and serotonin syndrome
NMS - lead pipe rigidity, reduced reflexes, onset over days
Serotonin syndrome - increase tone ++, increased reflexes and clonus, onset over hours
What is the only proven benefit of IV pre-endoscopic PPI in acute UGIB
Reduced endoscopic intervention
No reduction in mortality or rebleeding rate
What bacteria in reactive arthritis are HLA-B27 associated
Chlamydia trachomatis
Clostridium difficile
Salmonella
Shigella
Campylobacter
Yersinia
Intravesical BCG
What type of SpA would you use conventional DMARDs in?
Peripheral SpA
No role in axial SpA
Sulfasalazine or MTX
What TNFi do you use in SpA if pt has uveitis or IBD
Infliximab or adalimumab
NOT etanercept
Secukinumab MOA + indication
IL-17A inhibitor - also ixekizumab
Used in axial SpA and psoriatic arthritis
Similar efficacy to TNFi
Ustekinumab MOA and indication
IL-12/IL-23 monoclonal antibody
Effective for enthesitis and psoriasis
Not useful for axial SpA
What management reduces mortality in COPD
Long-term oxygen therapy in pts with PaO2 <55mmHg
What benefits does pulmonary rehab give in COPD pts
Reduction in symptoms (dyspnoea + fatigue), anxiety and depresseion, exercise capacity, peripheral muscle function
Reduces exacerbations requiring hospitalisation
NO improvement in mortality
King’s College Criteris for liver transplant in paracetamol-induced liver failure
Arterial pH <7.3
OR
Grade III or IV encephalopathy AND prothrombin time >100s AND serum Cr >301micromol/L
King’s College Criteria for liver transplant in non-paracetamol induced liver failure
Prothrombin time >100s (INR >6.5)
OR
Any 3 of the following:
- Age <10 years or >40 years
- Non hep A or B viral hepatitis, halothane hepatitis, idiosyncratic drug reactions
- Duration of jaundice before encephalopathy >7 days
- PT >50s
- Bili >18mg/dL (308micromol/L)
Dermatomyositis antibodies
Anti-mi2
TIF-1gamma - associated with malignancy
MDA-5 - cutaneous ulceration overlying Gottron papules, mechanic’s hands - a/w rapidly progressive ILD
MJ
Reason for giving anti-androgen treatment with goserelin (GnRH agonist) for prostate cancer
Reduce flare symptoms related to increase in LH production
Measles incubation period
6-21 days
Cerebral venous sinus thrombosis management
LMWH or UFH
Presence of haemorrhage NOT contraindications for anticoagulation
Long term anticoagulation - wafarin or dabigatran
Tacrolimus ADR
Hyperglycaemia, diabetes
Diarrhoea headache tremor nausea
Alopecia, hirsutism
Nephrotoxicity - dose-related in acute, can be irreversible in chronic
Metabolised by CYP 3A4
ECG findings of ARVD
V1-5 T wave inversion and epsilon waves
Exercise or stress can precipitate CT
Define extensively drug-resistant TB
MDR TB + resistance to moxifloxacin and amikacin
Hummingbird sign
PSP
Hot cross bun sign MRI
MSA - cerebellar type
What features are seen in atypical parkinsonism rather than idiopathic PD
Rapid progression of gait impairment <5 years
No response to high-dose levodopa despite mod severity of disease
Severe autonomic failure in first 5 years
Recurrent falls from imbalance within 3 years
Absence of common non-motor features of PD despite 5 years of disease
Early bulbar dysfunction
Inspiratory respiratory dysfunction
