genitourinary disorders
Renal Tubular Acidosis
Key Points
Renal tubular acidosis is a class of disorders in which excretion of hydrogen ions or reabsorption of filtered bicarbonate is impaired, leading to a chronic metabolic acidosis with a normal anion gap. RTA is usually due to abnormalaldosteroneproduction or response (type 4), or less often, due to impaired hydrogen ion excretion (type 1) or impaired bicarbonate resorption (type 2). Consider RTA if patients have metabolic acidosis with a normal anion gap or unexplained hyperkalemia Check ABG and serum electrolytes, BUN, and creatinine, and urine pH. Do other testing to confirm type of RTA (eg, acid load test for type 1, bicarbonate infusion for type 2). Treat using alkali therapy and measures to correct low serum potassium in type 2 and sometimes type 1 RTA , and using potassium restriction or potassium-wasting diuretics in type 4 RTA; give other electrolytes as needed. 