Hormonal control of water and sodium balance

5 Written Questions

1. -Osmotic diarrhea
   -osmotic diuresis
   -inadequate replacement of insensible water loss
   -diabetes insipidus
2. Results in water loss and volume depletion of the extracellular space
3. -Results from gain of both water and sodium, but relatively more water than sodium
   -patients have clinical signs of volume overload
   -typically seen in conditions with total body volume overload but low effective intravascular volume
   CHF → low cardiac output
   cirrhosis → low plasma oncotic pressure
   nephrotic syndrome → "
   -urinary sodium is very low
4. -does not lead to severe volume overload and edema, as you might expect.
   -Intrinsic renal mechanisms and atrial natriuretic peptide action (which blocks sodium reabsorption in the medullary collecting duct) help to excrete some of the excess volume
5. Categorized based on the observed volume status of the patient
   -can be euvolemic, hypovolemic or hypervolemic

5 Matching Questions

1. Treatment of neurogenic diabetes insipidus
2. Osmolality
3. Uncommon cause of hyponatremia
4. Renin function
5. Glucose

1. a DRINK WATER
   -In partial DI → high-dose DDAVP
   -in complete DI → diuretics are given to increase the proportion of salt and water that is reabsorbed in the proximal tubule, decreasing the dependence on water reabsorption in the distal nephron
2. b Measure of the number of particles in the solution
3. c Loss of sodium from the blood in excess of water
4. d converts angiotensenogen → angiotensin 1
5. e -under normal circumstances, can move into cells and is an ineffective osmol
   -in cases where uptake is impaired(Hyperglycemia and diabetes), glucose effects tonicity

5 Multiple Choice Questions

1. -Potassium
   -organic phosphate (ATP, phospholipids)
   1. osmols of the ICF
   2. Normal osmolality
   3. Hyponatremia
   4. Osmolality
2. -In activating mutation of 11B HSD-2
   -prevents cortisol conversion to cortisone allowing activation of the MR causing sodium retention and hypertension
   1. Treatment of SIADH
   2. acquired SAME
   3. Causes of SIADH
   4. cause of SAME
3. Address the underlying problem
   1. Renin levels in primary hyperaldosteronism
   2. Secondary hyperaldosteronism
   3. Treatment of Secondary hyperaldosteronism
   4. Treatment of primary hyperaldosteronism
4. Excess total body water
   1. euvolemic hyponatremia
   2. Hyponatremia
   3. Sodium
   4. Aldosterone
5. -Present similarly to primary hyperaldosteronism but renin and aldosterone levels are low
   1. Treatment of primary hyperaldosteronism
   2. Angiotensin-converting enzyme (ACE)
   3. Syndrome of apparent mineralocorticoid excess (SAME)
   4. Primary hyperaldosteronism

5 True/False Questions

1. If both hypoosmolar and hypovolemic, which wins? → -non-sodium effective osmol (Glucose in the setting of uncontrolled diabetes) accumulates in the plasma raising ECF osmolality
   -causes a shift of water from ICF → ECF
   -water it helps normalize ECF osmolality but dilutes sodium concentration

   True        False

2. euvolemic hyponatremia → Categorized based on the observed volume status of the patient
   -can be euvolemic, hypovolemic or hypervolemic

   True        False

3. Presentation of primary hyperaldosteronism → -Surgical removal of tumors
   -medical therapy with mineralocorticoid antagonists such as spironolactone or eplerenone

   True        False

4. ECF compartments → -Intravascular
   -extravascular/interstitial spaces

   True        False

5. Treatment of severe/acute hyponatremia due to SIADH → Address the underlying problem

   True        False