Fanconi syndrome

[Jason Yan]

Fanconi syndrome is a rare disorder of kidney tubule function that results in excess amounts of glucose, bicarbonate, phosphates (phosphorus salts), uric acid, potassium, and certain amino acids being excreted in the urine.
(See also Introduction to Disorders of Kidney Tubules.)
Fanconi syndrome is unrelated to—and should not be confused with—Fanconi anemia.
Fanconi syndrome may be hereditary or may be caused by

Exposure to certain drugs (including some chemotherapy and antiretroviral drugs)
Exposure to heavy metals or other chemicals
Vitamin D deficiency
Kidney transplantation
Multiple myeloma
Amyloidosis

Fanconi syndrome usually occurs with another hereditary disorder, such as cystinosis. Cystinosis is an inherited disorder of amino acid metabolism characterized by abnormal deposits of the amino acid cystine throughout the body and abnormal concentrations of cystine in the urine. Abnormal cystine deposits cause eye disorders, an enlarged liver, and an underactive thyroid gland.