Fanconi syndrome describes a generalised reabsorptive disorder of renal tubular transport in the proximal convoluted tubule resulting in:

• type 2 (proximal) renal tubular acidosis
• polyuria
• aminoaciduria
• glycosuria
• phosphaturia
• osteomalacia

Causes

• cystinosis (most common cause in children)
• Sjogren's syndrome
• multiple myeloma
• nephrotic syndrome
• Wilson's disease

Generalized reabsorption defect in PCT p q excretion of amino acids, glucose, HCO3–, and PO43–, and all substances reabsorbed by the PCT

Effect: Metabolic acidosis (proximal RTA), hypophosphatemia, hypokalemia

Causes Hereditary defects (eg, Wilson disease, tyrosinemia, glycogen storage disease), ischemia, multiple myeloma, drugs (eg, ifosfamide, cisplatin, tenofovir, lead poisoning

Notes Growth restriction and rickets/osteopenia common due to hypophosphatemia

Volume depletion also common