Nephrolithiasis specifically refers to calculi in the kidneys. Ureteral calculi almost always originate in the kidneys, although they may continue to grow once they lodge in the ureter and at that time are called ureterolithiasis.  Lifetime incidence of kidney stones is approximately 13% for men and 7% for women. Although often asymptomatic—incidental stones are identified… Read more »

Renal tubular acidosis type 4

Type IV renal tubular acidosis (RTA), or hyperkalemic RTA or tubular hyperkalemia, refer to cases with normal renin and aldosterone production but impaired tubular responsiveness, usually caused by a distal tubular voltage defect.  It often occurs in diabetics. Acidosis usually is mild and asymptomatic, and is usually discovered during routine labs. Because several commonly used drugs may… Read more »

Renal tubular acidosis type 2

Disorder of proximal nephron – defective bicarbonate reabsorption in proximal tubule (usually as a part of generalized tubular disorder – Fanconi syndrome) Large amount of bicarbonate is excreted; characterized by normal anion gap acidosis and hypokalemia. Urine may become maximally acid – pH below 5.5. Daily acid excretion is normal, but fractional bicarbonate excretion is… Read more »

Bartter’s Syndrome

Bartter’s syndrome is an autosomal recessive disorder of unknown pathophysiology characterized by hypokalemia (due to renal potassium wasting), metabolic alkalosis, and low or normal blood pressure.  The condition is caused by a defect in the kidney’s ability to reabsorb sodium. Persons with Bartter’s syndrome lose too much sodium through the urine. This causes a rise in the… Read more »

Acute Renal Failure

The RIFLE classification of Acute Renal Failure is as follows: Risk (R) – Increase in serum creatinine level X 1.5 or decrease in GFR by 25%, or urine output <0.5 mL/kg/h for 6 hours Injury (I) – Increase in serum creatinine level X 2.0 or decrease in GFR by 50%, or urine output <0.5 mL/kg/h for… Read more »