Water & Electrolytes & Infections Flashcards
(18 cards)
What is the most common complication arising as a result of chronic kidney disease. Give some others
Hyperkalaemia, then volume overload and metabolic acidosis
What can an acute increase in renal perfusion pressure cause?
Increases Na excretion, and also GFR (based on animal models)
Which effect of aldosterone is most important for potassium excretion?
Increasing Na/K/ATPase channel
At which GFR should dialysis commence for a CKD patient
15 ml/min
Which effect of the kidney causes the biggest increase in BP? Give another
Increased angiotensin II, then increased water reabsorption
What would isotonic saline increase?
Extracellular water
What is the most common cause of hyperchloraemic acidosis? Give another.
Diarrhoea, then renal failure
What is the most common cause of chronic kidney disease? Give another.
Diabetes, then Hypertension
What is the common ECG finding in a patient with hyperkalaemia? Give the rest, in sequence.
Tall (tented/peaked) T-waves, followed by absent P-waves then broad QRS complexes
A patient who has recently undergone heart valve surgery presents with a fever. Cultures reveal a gram positive, catalase positive cocci. What is the most likely diagnosis?
Staph aureus
Following a chest infection which was treated with co-amoxiclav, a patient subsequently develops diarrhoea and severe abdominal pain and a high fever. What is the most likely diagnosis?
C diff colitis
Name the bacterium that produces the TSST-1 superantigen?
Staph aureus
Give a complete definition of superantigen.
An antigen that binds MHCII outside the antigen groove and the T cell variable receptor, activating a substantial proportion of T lymphocytes without need for antigen processing or conventional presentation.
Briefly describe Strep pneumoniae and its virulence factors.
A gram positive facultative anaerobe coccus. It is both alpha and beta haemolytic (given alpha). Pneumolysin is a protein that can cause lysis of host cells. PspA inhibits complement activation. The polysaccharide capsule. Autolysin is a protein that lyses bacteria, releasing internal contents.
Describe routes of infection of prosthetic valve endocarditis.
Organism can have direct access to the prosthesis and to the perivalvular tissue. Organism can enter bloodstream through broken skin or via interventions. Organism can bind to host proteins such as fibronectin.
Give some details of the primary host response to superantigen which may lead to sepsis.
Mast cell IgE cross-linking results in the release of inflammatory mediators, T lymphocytes produce TNF-a, IL-2 and IFN-y.
What is the most common portal of entry for infection caused by E. coli in adults
Urinary traction
Describe C diff and its virulence factors.
Anaerobic gram positive spore forming rod/bacillus. Primary virulence factors are to two toxins: toxin A (TcdA) and toxin B (TcdB)
