Renal tubular acidosis

Last reviewed: 30 Aug 2023
Last updated: 21 Dec 2021



History and exam

Key diagnostic factors

  • growth retardation
  • muscular weakness
  • failure to thrive (children)
  • hypoglycemia after fructose ingestion
  • rickets
  • ethnicity/national origin
  • nephrolithiasis
More key diagnostic factors

Other diagnostic factors

  • sensorineural hearing loss
  • liver dysfunction
  • osteopenia, osteopetrosis, nephrocalcinosis, and cerebral calcifications
  • nephrocalcinosis
  • Kussmaul breathing
  • ocular abnormalities (cataracts, glaucoma, band keratopathy), growth retardation, impaired intellect, and calcification of basal ganglia
Other diagnostic factors

Risk factors

  • childhood
  • urinary tract obstruction
  • diabetes mellitus
  • primary biliary cirrhosis
  • nephrocalcinosis
  • nephrolithiasis
  • amphotericin-B therapy
  • toxic exposure to heavy metals, and cis-platinum
  • untreated primary adrenal insufficiency
  • family history of inherited RTA
  • older men
  • hereditary fructose intolerance
  • Wilson disease
  • galactosemia
  • disorders of mitochondrial metabolism
  • glycogen storage diseases
  • tyrosinemia
  • Lowe syndrome
  • lead exposure
  • cadmium exposure
  • ifosfamide therapy
  • cystinosis
  • cyclosporine therapy
  • angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blocking drugs
  • heparin therapy
  • medications interfering with sodium transport
  • use of carbonic anhydrase inhibitors
  • abnormalities of filtered immunoglobulins
  • interstitial nephritis
  • hyperparathyroidism
  • environmental exposure to aristolochic acid
  • Thai or southeast Asian ancestry
  • cis-platinum therapy
  • toluene, paraquat, lysol exposure
  • Dent disease
  • ibuprofen overdose
  • lamivudine
  • antiviral therapy (cidofovir, adefovir, or tenofovir)
  • programmed cell death protein 1 (PD-1)-inhibitors
More risk factors

Diagnostic investigations

1st investigations to order

  • serum bicarbonate
  • serum chloride
  • serum sodium
  • serum potassium
  • arterial blood pH
  • serum anion gap
  • urine pH
More 1st investigations to order

Investigations to consider

  • serum aldosterone
  • urine anion gap
  • measurement of fractional bicarbonate excretion
  • urine PCO₂ bicarbonate infusion
  • furosemide test
  • ammonium chloride loading test
  • furosemide and fludrocortisone test
  • urine glucose
  • tubular maximum (Tm) reabsorption of phosphate
  • fractional excretion of amino acids
  • ultrasound
  • CT/spiral CT
  • nuclear renal scan
More investigations to consider

Emerging tests

  • molecular genetic testing for hereditary distal RTA (type I)

Treatment algorithm


classic distal RTA (type I)

proximal RTA (type II) including Fanconi syndrome

mixed proximal and distal DTA (type III)

hyperkalemic distal RTA (type IV) + mineralocorticoid deficiency

hyperkalemic distal RTA (type IV) + mineralocorticoid-resistant



Ashish Verma, MBBS

Assistant Professor of Medicine

Section of Nephrology

Department of Medicine

Boston University School of Medicine/Boston Medical Center




AV declares that he has no competing interests.


Dr Ashish Verma would like to gratefully acknowledge Dr Melvin E. Laski, Dr Elizabeth Cobb, Dr Rebin Titus, and Dr Abeer Kaldas, previous contributors to this topic.


MEL, EC, and AK declare that they have no competing interests; RT's competing interests are not disclosed.

Peer reviewers

Daniel Batlle, MD


Northwestern University




DB declares that he has no competing interests.

Troels Ring, MD

Department of Nephrology

Aalborg Hospital




TR declares that he has no competing interests.

Use of this content is subject to our disclaimer