Miscellaneous Flashcards
What is the function of protein S?
Cofactor of protein C
Inhibits factors Va and VIIIa
What is the function of protein C?
Inhibits factors Va and VIIIa
How is multiple myeloma diagnosed?
>10% clonal bone marrow plasma cells in biopsy
PLUS one of the CRAB features
What are the 5 most common inherited hypercoagulable states?
- Factor V Leiden mutation
- Prothrombin gene mutation G20210A
- Protein S deficiency
- Protein C deficiency
- Antithrombin deficiency
Are petechiae more characteristic of disorders of coagulation (clotting factor deficiencies) or purpuric disorders (platelets and blood vessels)?
Purpuric disorders
Are joint haemorrhages and soft tissue haematomas more characteristic of disorders of coagulation (clotting factor deficiencies) or purpuric disorders (platelets and blood vessels)?
Disorders of coagulation
Which diseases are associated with mutations in the janus kinase 2 (JAK2) gene?
Myeloproliferative neoplasms e.g. polycythemia vera, essential thrombocytopenia, myelofibrosis
Which type of cell is pathognomonic for Hodgkin’s lymphoma?
Reed-Sternberg cells (RSCs)
Which NOAC(s) have a reversal agent?
Dabigatran only (idarucizumab)
What is the reversal agent for dabigatran?
Idarucizumab
What are the four types of thalassemia major?
Silent carrier/minima (-a/aa)
Alpha thalassemia trait/minor (-a/-a or –/aa)
Haemoglobin H disease/alpha thalassemia major (–/-a)
Haemoglobin Bart disease (–/–)
Which three types of haemoglobin are typically found in adult blood?
HbA (ααββ) >95%
HbA2 (ααδδ) 2-3%
HbF (ααγγ) 1%
Levels of which types of haemoglobin are increased in people with beta thalassemia?
HbF (ααγγ)
HbA2 (ααδδ)
Levels of which types of haemoglobin are increased in people with alpha thalassemia?
HbH (ββββ)
Hb Bart (γγγγ)
Is adrenaline predominantly an inotrope and/or a vasopressor?
Inotrope (increases myocardial contractility)
Is noradrenaline predominantly an inotrope and/or a vasopressor?
Vasopressor (causes vasoconstriction, leading to increased systemic and/or pulmonary vascular resistance)
Which vasoactive agent is first-line for septic shock?
Noradrenaline
What is a rouleaux?
Stack of RBCs
Occur when the plasma protein concentration is high e.g. infections, MM
Can impair blood flow through capillaries
What is the most notable adverse effect of Tazocin (piperacillin with tazobactam)?
Transient increases in liver enzymes and bilirubin, cholestatic jaundice
What is a Jarisch-Herxheimer reaction?
Acute, transient reaction to bacterial endotoxins and pyrogens released after initiation of antibiotic therapy in patients with syphilis
Flu-like symptoms, tachypnoea, hypotension, tachycardia, exanthem
Why is clavulanic acid given with amoxicillin?
Clavulanic acid is a ß-lactamases inhibitor
ß-lactamases are secreted by some bacteria and they inhibit the effects of ß-lactam antibiotics (penicillins)
On which receptors does noradrenaline act?
Alpha 1 (vasoconstriction)
Beta 1 (heart → increased CO)
Reflex bradycardia often occurs due to increased MAP
On which receptors does adrenaline act?
Potent
Beta 1 (inotropic and chronotropic → increased CO)
Weak
Beta 2 (vasodilation offset by alpha 1 vasoconstriction)
Alpha 1 (vasoconstriction offset by beta 2 vasodilation)
At high doses, alpha 1 activity predominates, increasing systemic vascular resistance and therefore BP
Which antibiotics are beta lactams?
- Penicillins
- Cephalosporins
- Monobactams (aztreonam)
- Carbapenems “-penem”
What is an ECOG score?
A measure of how a disease impacts a person’s daily living. Initially made for oncological purposes
How do you calculate an anion gap?
[Na+ + K+] - [Cl- + HCO3-]
Normal: 10-16 mmol/L
What can cause a high anion gap acidosis?
- Increased organic acids - no compensatory increase in Cl-*
- TLKR (total left knee replacement)* mneumonic
L - lactate
T - toxins (paracetamol, isoniazid, metformin, methanol, ethanol)
K - ketones (diabetic and alcoholic)
R - renal failure
How are autoimmune haemolytic anaemias distinguished from non-autoimmune?
Coombs test
What are 4 causes of corpuscular haemolytic anaemia?
- Membrane defect*
1. Hereditary spherocytosis
2. Paroxysmal nocturnal haemoglobinuria - Enzyme defect*
3. G6PD deficiency
4. Pyruvate kinase deficiency - Haemoglobinopathy*
5. Sickle cell disease
6. Thalassemia
7. Haemoglobin C disease
What are 4 causes of extracorpuscular haemolytic anaemia?
- Isoimmune*
1. AB0 incompatibility
2. Rhesus incompatibility - Autoimmune*
3. Cold/warm agglutinin disease - Microangiopathic*
4. HUS
5. TTP
6. SLE - Macroangiopathic*
7. Aortic stenosis, valve replacement, dialysis
8. Exertional e.g. running, walking on hard surfaces
What are haptoglobin levels used for?
Distinguishing intra- and extravascular haemolysis
Haemoglobin released from broken down RBCs binds to haptoglobin, decreasing free circulating haptoglobin
Occurs mostly in intravascular haemolysis (i.e. not spleen or liver)
What generation cephalosporin is ceftriaxone?
3rd
(strong Gram - cover and some +)
What generation cephalosporin is cefazolin?
1st
(used for Gram +)
Which antibiotic is used for MRSA?
Vancomycin
What are the major adverse effects of aminoglycosides?
Nephrotoxicity
Ototoxicity
Gentamycin
Why do people with lymphoma get autoimmune haemolytic anaemia?
Dysfunctional T cells → failed negative selection → self-reactive B cells against RBCs
Why do people with lymphoma have hypogammaglobulinaemia?
Dysfunctional T cells → decreased B cell activation (IL-4)
OR
Dysfunctional B cells → impaired stimulation of immunoglobulin production
Which immunoglobulins are involved in the primary and secondary immune responses?
Primary: IgM (first encounter)
Secondary: IgG (subsequent encounters)
What is a pannus?
Abnormal layer of fibrovascular/granulation tissue
How can a PE lead to a metabolic acidosis?
Hypoxia → lactic acidosis
What is an antalgic gait?
A limb that develops to avoid weight-bearing on a leg
e.g., sprained ankle
What are the indications for hypertonic saline in the treatment of hyponatremia?
Seizures
Obtundation (altered level of consciousness)
Coma
Respiratory distress
What causes hypermagnesemia?
Renal failure
Rhabdomyolysis (release of Mg from muscles)
Magnesium administration e.g., pre-eclampsia
What is the function of magnesium?
A calcium antagonist
Prevents the intra-cellular movement of calcium
Low Mg → low serum Ca
Which hormone is primarily responsible for phosphate regulation?
PTH
Causes phosphate excretion
