MEDICINE NEPHROLOGY CLINICAL CASES
AND STEP BY STEP DIAGNOSTIC
EXPLANATIONS 2026 STUDY GUIDE
◉ Diluting segment
Answer: A segment of the nephron that reabsorbs solute without
water; the thick ascending limb and the distal convoluted tubule are
active salt-reabsorbing segments that are not permeable by water.
◉ Hyperchloremic metabolic acidosis
Answer: A shift in body electrolyte and pH balance involving
elevated serum chloride, diminished bicarbonate concentration, and
a decrease in pH in the blood. Typical result of bicarbonate diuresis.
◉ Hypokalemic metabolic alkalosis
Answer: A shift in body electrolyte balance and pH involving a
decrease in serum potassium and an increase in blood pH. Typical
result of loop and thiazide diuretic actions.
◉ Nephrogenic diabetes insipidus
, Answer: Loss of urine-concentrating ability in the kidney caused by
lack of responsiveness to antidiuretic hormone (ADH is normal or
high).
◉ Pituitary diabetes Insipidus
Answer: Loss of urine-concentrating ability in the kidney caused by
lack of antidiuretic hormone (ADH is low or absent).
◉ Potassium-sparing diuretic
Answer: A diuretic that reduces the exchange of potassium for
sodium in the collecting tubule; a drug that increases sodium and
reduces potassium excretion. Example: aldosterone antagonists.
◉ Uricosuric diuretic
Answer: A diuretic that increases uric acid excretion, usually by
inhibiting uric acid reabsorption in the proximal tubule. Example:
ethacrynic acid.
◉ Carbonic Anhydrase Inhibitors
Answer: Example: Acetazolamide. MOA: Acts in PCT - inhibits
carbonic anhydrase. Effects: Bicarbonate diuresis, metabolic
acidosis, K+ wasting. Uses: Glaucoma, altitude sickness, metabolic
alkalosis. Toxicity: Renal stones, hyperammonemia in liver disease.
AND STEP BY STEP DIAGNOSTIC
EXPLANATIONS 2026 STUDY GUIDE
◉ Diluting segment
Answer: A segment of the nephron that reabsorbs solute without
water; the thick ascending limb and the distal convoluted tubule are
active salt-reabsorbing segments that are not permeable by water.
◉ Hyperchloremic metabolic acidosis
Answer: A shift in body electrolyte and pH balance involving
elevated serum chloride, diminished bicarbonate concentration, and
a decrease in pH in the blood. Typical result of bicarbonate diuresis.
◉ Hypokalemic metabolic alkalosis
Answer: A shift in body electrolyte balance and pH involving a
decrease in serum potassium and an increase in blood pH. Typical
result of loop and thiazide diuretic actions.
◉ Nephrogenic diabetes insipidus
, Answer: Loss of urine-concentrating ability in the kidney caused by
lack of responsiveness to antidiuretic hormone (ADH is normal or
high).
◉ Pituitary diabetes Insipidus
Answer: Loss of urine-concentrating ability in the kidney caused by
lack of antidiuretic hormone (ADH is low or absent).
◉ Potassium-sparing diuretic
Answer: A diuretic that reduces the exchange of potassium for
sodium in the collecting tubule; a drug that increases sodium and
reduces potassium excretion. Example: aldosterone antagonists.
◉ Uricosuric diuretic
Answer: A diuretic that increases uric acid excretion, usually by
inhibiting uric acid reabsorption in the proximal tubule. Example:
ethacrynic acid.
◉ Carbonic Anhydrase Inhibitors
Answer: Example: Acetazolamide. MOA: Acts in PCT - inhibits
carbonic anhydrase. Effects: Bicarbonate diuresis, metabolic
acidosis, K+ wasting. Uses: Glaucoma, altitude sickness, metabolic
alkalosis. Toxicity: Renal stones, hyperammonemia in liver disease.
