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:
- Electrolytes
- bicarbonates
- potassium
- Vitamin D
- phosphates
- water (when the child is dehydrated)
- other minerals and nutrients
