Resumen

• RTA is rarely symptomatic.
• Patients with severe acidaemia can show hyperventilation or Kussmaul's breathing due to respiratory compensation.
• Patients with RTA have a low arterial pH and serum bicarbonate with hyperchloraemia and a normal serum anion gap.
• The urine pH exceeds 5.5 in classic distal RTA, but is lower than 5.0 in patients with untreated proximal RTA.
• Alkali therapy is the mainstay of treatment.
• Potassium supplementation may be required for hypokalaemia, and low-potassium diets are used if hyperkalaemia is present.
• If hyperkalaemic distal RTA is due to mineralocorticoid deficiency, fludrocortisone can be given.
• Fanconi's syndrome is a subset of proximal RTA, representing a generalised dysfunction of the proximal tubule, with the resultant urinary loss of bicarbonate, calcium, phosphate, urate, amino acids, glucose, and other organic acids and bases.
• In children, Fanconi's syndrome results in growth retardation, renal rickets, and severe metabolic acidosis. Adult cases exhibit similar urinary losses, but the clinical impact is largely restricted to metabolic acidosis.
• Fanconi's syndrome is marked by the appearance in the urine of all amino acids. Specific amino aciduria as seen in isolated cystinuria, glucose loss in isolated glycosuria, and isolated phosphaturia do not constitute Fanconi's syndrome.