Metabolic Acidosis Questions & Answers

Updated: Oct 10, 2018
  • Author: Christie P Thomas, MBBS, FRCP, FASN, FAHA; Chief Editor: Vecihi Batuman, MD, FASN  more...
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Questions & Answers

Overview

What is metabolic acidosis?

What are acids and bases in the pathogenesis of metabolic acidosis?

What is the difference between a strong acid and a weak acid in the pathogenesis of metabolic acidosis?

How does the law of mass action apply in the pathogenesis of metabolic acidosis?

What is the role of hydrogen ions in the pathogenesis of metabolic acidosis?

What processes must take place to maintain a physiologic [H+] of 40 nEq/L?

What is the role of buffers in the pathogenesis of metabolic acidosis?

What is the role of the HCO3-/H2 CO3 buffering system in the pathogenesis of metabolic acidosis?

What is the role of intracellular buffers in chronic metabolic acidosis?

What causes respiratory acidosis?

What is the role of metabolism of proteins and dietary phosphate in the pathogenesis of metabolic acidosis?

What is the role of pH level maintenance in the pathogenesis of metabolic acidosis?

What is the role of reabsorption of HCO3- in the pathogenesis of metabolic acidosis?

What is the role of excretion of the daily acid load in the pathogenesis of metabolic acidosis?

What is titratable acidity?

What does ammonia (NH3) buffer in the pathogenesis of metabolic acidosis?

What is the role of ammonia (NH3) in the pathogenesis of metabolic acidosis?

What is the role of acidemia and alkalemia in the pathogenesis of metabolic acidosis?

What is the effect on pH and HCO3 concentrations when metabolic acidosis is part of a mixed or complex acid-base disturbance?

What is the likely compensatory response to metabolic acidosis?

How is metabolic acidosis diagnosed?

What serum HCO3- levels suggest metabolic acidosis and renal failure?

What is the characterization of chronic uremic acidosis?

What is the anion gap (AG) in metabolic acidosis?

What can result from an increase in the anion gap (AG) in patients with metabolic acidosis?

How is metabolic acidosis classified in relation to the anion gap (AG)?

When is calculating the urinary anion gap (AG) helpful in metabolic acidosis?

What is suggested by a positive urine anion gap (AG) in non-AG metabolic acidosis?

What effect does ketonuria have on the urinary anion gap (AG) in metabolic acidosis?

What is the role of renal acid secretion in the pathogenesis of metabolic acidosis?

What is the role of hypokalemia in the pathogenesis of metabolic acidosis?

What is the most common cause of hypokalemia in metabolic acidosis?

What is the role of hyperkalemia in the pathogenesis of metabolic acidosis?

How is metabolic acidosis classified?

What is the cause of non-anion gap (AG) (hyperchloremic) metabolic acidosis?

What mnemonic is used to remember the causes of non-anion gap (AG) metabolic acidosis?

Which conditions cause a non-anion gap (AG) metabolic acidosis?

Which conditions are associated with high anion gap (AG) metabolic acidosis?

What are the mnemonics used to recall the differential diagnoses of high anion gap acidosis?

What is the role of plasma osmolality in determining the cause of high anion gap (AG) acidosis?

How does loss of HCO3- via the GI tract cause non-anion gap (AG) (hyperchloremic) metabolic acidosis?

How does distal renal tubular acidosis (RTA) (type 1) cause non-anion gap (AG) (hyperchloremic) metabolic acidosis?

When should type 1 renal tubular acidosis (RTA) be suspected in patients with non-anion gap (AG) (hyperchloremic) metabolic acidosis?

What causes distal renal tubular acidosis (RTA) (type 1) in patients with non-anion gap (AG) (hyperchloremic) metabolic acidosis?

How does a defect in Na+ reabsorption cause distal renal tubular acidosis (RTA) (type 1) in patients with metabolic acidosis?

How does potassium wasting occur in distal renal tubular acidosis (RTA) (type 1) metabolic acidosis?

What does high urine pH in patients with type 2 renal tubular acidosis (RTA) suggest?

What causes nephrocalcinosis and nephrolithiasis in patients with type 1 renal tubular acidosis (RTA)?

What are the causes of distal renal tubular acidosis (RTA) (type 1)?

What are the genetic forms of type 1 renal tubular acidosis (RTA)?

What is the pathogenesis of proximal (type 2) renal tubular acidosis (RTA)?

What is the appearance of type 2 renal tubular acidosis (RTA)?

Which proximal tubular disorders may cause metabolic acidosis?

What is the role of the proximal tubule in the pathogenesis of Fanconi syndrome?

What are the symptoms of type 2 renal tubular acidosis (RTA)?

Which findings suggest type 2 renal tubular acidosis (RTA)?

What causes osteomalacia in patients with type 2 renal tubular acidosis (RTA)?

What are the causes of proximal (type 2) renal tubular acidosis (RTA)?

What are the causes of isolated proximal (type 2) renal tubular acidosis (RTA)?

What is type 4 renal tubular acidosis (RTA)?

What is the role of hyperkalemia in type 4 renal tubular acidosis (RTA)?

Which findings suggest type 4 renal tubular acidosis (RTA)?

When should type 4 renal tubular acidosis (RTA) be suspected?

How are transtubular potassium gradient (TTKG) levels interpreted in the workup of type 4 renal tubular acidosis (RTA)?

What causes type 4 renal tubular acidosis (RTA)?

What are the genetic forms of type 4 renal tubular acidosis (RTA)?

Which patients are at increased risk for developing metabolic acidosis?

What is the primary defect in non-anion gap (AG) (hyperchloremic) metabolic acidosis?

How does hypobicarbonatemia increase the risk of developing metabolic acidosis?

What causes non-anion gap (AG) (hyperchloremic) metabolic acidosis in patients undergoing urinary diversion procedures?

How does infusion of acids cause non-anion gap (AG) (hyperchloremic) metabolic acidosis?

What is the role of L-lactate in the pathogenesis of metabolic acidosis?

How is lactate metabolized?

What is the major metabolic pathway for pyruvate in the pathogenesis of lactic acidosis?

How does lactic acid accumulate and what serum level is considered diagnostic of lactic acidosis?

How are type A and type B lactic acidosis differentiated?

What is D-lactic acidosis?

What is the role of free fatty acids in the pathogenesis of ketoacidosis?

What is the pathogenesis of alcoholic ketoacidosis?

What are the causes of starvation ketoacidosis?

What is diabetic ketoacidosis (DKA)?

What causes metabolic acidosis in patients with advanced chronic kidney disease?

What is the sequelae of chronic uremic acidosis?

What is the role of salicylates in high-anion gap (AG) acidosis?

What is the role of salicylic acid in the pathogenesis of metabolic acidosis?

What is the role of methanol in the pathogenesis of metabolic acidosis?

What is the role of formaldehyde in the pathogenesis of metabolic acidosis?

In addition to metabolic acidosis, what is the clinical manifestation of methanol poisoning?

What is the role of ethylene glycol in the pathogenesis of metabolic acidosis?

What is the prognosis of metabolic acidosis?

Presentation

What are the signs and symptoms of metabolic acidosis?

What should be the focus of the history in patients with suspected metabolic acidosis?

What is the best recognized sign of metabolic acidosis and how is it characterized?

What are the signs of chronic metabolic acidosis in children?

Which symptoms suggest acute severe metabolic acidosis?

Which physical signs of metabolic acidosis may help identify the underlying cause?

DDX

What are the differential diagnoses for Metabolic Acidosis?

Workup

What is the role of serum electrolyte measurement in the workup of metabolic acidosis?

What is the basis of a definitive diagnosis of metabolic acidosis?

How is the diagnosis of metabolic acidosis made?

How is the osmolar gap calculated when the anion gap (AG) is elevated in the workup of metabolic acidosis?

Which tests should be performed if the anion gap (AG) is not elevated in the workup of metabolic acidosis?

What is the role of the anion gap (AG) calculation in the workup of metabolic acidosis?

What is the role of the transtubular potassium gradient (TTKG) measurement in the workup of metabolic acidosis?

What is the role of plasma renin activity and plasma aldosterone testing in the workup of metabolic acidosis?

Which test is performed in the diagnosis of proximal renal tubular acidosis (RTA)?

What the role of the NH4 Cl loading test in the workup of metabolic acidosis?

When is urine-blood PaCO2 gradient measurement indicated in the workup of metabolic acidosis?

What is the role of imaging in the workup of renal tubular acidosis (RTA)?

What is the best indicator of the degree of acidosis/alkalosis?

What is the role of a WBC count in the workup of lactic acidosis?

Which urinalysis findings suggest metabolic acidosis?

When is calculating the urinary anion gap (AG) useful in the workup of metabolic acidosis?

What is the role of urine anion gap (AG) calculation in the workup of metabolic acidosis?

What does an elevated ketone level indicate in the workup of metabolic acidosis?

What is the role of a nitroprusside test in the workup of metabolic acidosis?

What is the normal plasma lactate concentration in metabolic acidosis?

At what plasma lactate level is lactic acidosis diagnosed?

What causes lactic acidosis?

Which salicylate level and iron level findings suggest metabolic acidosis?

What is the role of transtubular potassium gradient (TTKG) testing in the workup of metabolic acidosis?

Which transtubular potassium gradient (TTKG) findings indicate aldosterone deficiency or resistance in metabolic acidosis?

What is the role of plasma renin activity and plasma aldosterone levels in the workup of metabolic acidosis?

What is the role of fractional excretion of bicarbonate (FEHCO3-) testing in the workup of metabolic acidosis?

When is an ammonium chloride (NH4 Cl) loading test indicated in the workup of metabolic acidosis?

What is an alternative to the ammonium chloride (NH4 Cl) loading test in the workup of metabolic acidosis?

When is measuring the urine-blood PaCO2 gradient following an HCO3- load useful in the workup of metabolic acidosis?

What is the role of imaging studies in the workup of renal tubular acidosis (RTA)?

Which tests should be performed if iron ingestion is suspected in patients with metabolic acidosis?

When is an ECG) indicated in the workup of metabolic acidosis?

Treatment

When is treatment of acute metabolic acidosis indicated?

When is caution indicated in the correction of lactic acidosis and diabetic ketoacidosis (DKA)?

What agent is most commonly used to correct metabolic acidosis and how is administered?

How is the risk of hypernatremia and hyperosmolality minimized in the treatment of metabolic acidosis?

What are possible complications of alkali therapy for metabolic acidosis?

What are considerations for the treatment of high anion gap (AG) acidosis?

What is the role of potassium citrate in the treatment of metabolic acidosis?

When is oral NaHCO3 indicated for correction of metabolic acidosis?

What is the preferred therapy in patients with chronic metabolic acidosis?

How are citrate salts used in the treatment for metabolic acidosis?

What is the efficacy of potassium citrate for the correction of metabolic acidosis?

How is type 1 renal tubular acidosis (RTA) corrected?

How is type 2 renal tubular acidosis (RTA) corrected?

What is the risk of alkali therapy for type 2 renal tubular acidosis (RTA)?

What is a major treatment goal in type 4 renal tubular acidosis (RTA) and how is it achieved?

What is the role of fludrocortisone in the treatment of type 4 renal tubular acidosis (RTA)?

Why is treatment of chronic metabolic acidosis indicated in patients with chronic kidney disease (CKD)?

What is the treatment for chronic metabolic acidosis in patients with chronic kidney disease (CKD)?

Which agent is most frequently used to correct chronic metabolic acidosis in patients with chronic kidney disease (CKD)?

What are the benefits and risks of sodium bicarbonate in the treatment of chronic metabolic acidosis in patients with chronic kidney disease (CKD)?

How is metabolic acidosis caused by starvation and alcohol use treated?

How is diabetic ketoacidosis (DKA) treated?

What is the treatment for lactic acidosis?

What is the role of alkali therapy in lactic acidosis?

What is the role of lactic acid in the treatment for lactic acidosis?

What is the treatment for metabolic acidosis in patients with salicylate overdose?

How is the excretion of salicylate increased in the treatment of metabolic acidosis?

When is hemodialysis indicated in the treatment of patients with metabolic acidosis and salicylate poisoning?

How is methanol or ethylene glycol poisoning treated in patients with metabolic acidosis?

What is the role of ethanol in the treatment of metabolic acidosis?

What is administered to correct severe acidosis in methanol or ethylene glycol poisoning?

What is the role of folate in the treatment of metabolic acidosis?

When is hemodialysis indicated in the treatment of metabolic acidosis and methanol or ethylene glycol poisoning?

Medications

What agent is most commonly used to correct metabolic acidosis?

Which medications in the drug class Detoxification Agents are used in the treatment of Metabolic Acidosis?

Which medications in the drug class Antidiabetic Agents are used in the treatment of Metabolic Acidosis?

Which medications in the drug class Carbonic Anhydrase Inhibitors are used in the treatment of Metabolic Acidosis?

Which medications in the drug class Alkalinizing Agents are used in the treatment of Metabolic Acidosis?