Fanconi syndrome

The Fanconi syndrome is a generalized tubular disorder that leads to multiple transport abnormalities, including increased urinary loss of several substances.These include;

Loss of organic substrates – amino acids, glucose, bicarbonate, and organic acids
Loss of inorganic ions essential for mineral homeostasis – calcium, magnesium, sodium, potassium – and, perhaps most important clinically, phosphorus.

Causes:

Fanconi syndrome can be caused by faulty genes, or it may result later in life due to kidney damage. Sometimes the cause of Fanconi syndrome is unknown.

Common causes of Fanconi syndrome in children are genetic defects that affect the body’s ability to break down certain compounds such as:

Cystine (cystinosis)
Fructose (fructose intolerance)
Galactose (galactosemia)
Glycogen (glycogen storage disease)
Cystinosis is the most common cause of Fanconi syndrome in children.

Other causes in children include:

Exposure to heavy metals such as lead, mercury, or cadmium
Lowe syndrome, a rare genetic disorder of the eyes, brain, and kidneys
Wilson disease
Dent disease, a rare genetic disorder of the kidneys

In adults, Fanconi syndrome can be caused by various things that damage the kidneys, including:

Certain medicines, including azathioprine, cidofovir, gentamicin, and tetracycline
Kidney transplant
Light chain deposition disease
Multiple myeloma
Primary amyloidosis

Symptoms:

Symptoms of inherited FS can be seen as early as infancy. They include:

excessive thirst
Excessive urination
vomiting
Failure to thrive
Slow growth
Frailty
Low muscle tone
rickets
Corneal abnormalities
kidney disease

Symptoms of acquired FS include:

Bone disease
Muscle weakness
Low blood phosphate concentration (hypophosphatemia)
low blood potassium levels (hypokalemia)
excess amino acids in urine (hyperaminoaciduria)

Treatment:

Treatment of FS depends on its severity, cause, and the presence of other diseases. FS can’t typically be cured yet, but the symptoms can be controlled. The earlier the diagnosis and treatment, the better the outlook.

For children with inherited FS, the first line of treatment is to replace the essential substances that are being eliminated in excess by the damaged kidneys. Replacement of these substances may be by mouth or by infusion. This includes replacement of: