Rare acquired or inherited condition involving a
generalized transport defect in the proximal tubules with renal losses of
glucose, phosphate, calcium, uric acid, amino acids, and
bicarbonates, leading to short stature, osteomalacia, and renal failure.
Lignac De Toni Debré Syndrome; Fanconi Syndrome;
Renal Fanconi Syndrome; Fanconi Renal-Tubular Syndrome.
Genetic disorder but also can be caused by inborn errors of
metabolism, Wilson disease, Lowe syndrome, cystinosis, glycogenoses,
hereditary fructose intolerance, mitochondrial diseases, heavy-metal
poisoning, glue sniffing, and toxicity from some chemotherapeutic drugs.
Inherited form is estimated to occur in approximately
1:40,000 live births.
Autosomal dominant, but autosomal recessive
and X-linked transmission have been reported. Gene located on 15q15.3.
Syndrome may be inherited (idiopathic
familial), secondary to other genetic diseases or secondary to exposure to
certain toxins. Cystinosis is the most common genetic cause in childhood. Others are
galactosemia, Wilson disease, tyrosinemia, and glycogen storage diseases.
Toxins include heavy metals such as cadmium, lead, and mercury, ifosfamide,
gentamicin, expired tetracycline, and various solvents. The disease causes
failure of proximal renal tubular reabsorption.
Diagnosis is mainly clinical and biochemical. The
presenting symptoms are polyuria, polydipsia, and dehydration. The
biochemical findings are glucosuria with normal glycemia, hypophosphatemia,
hyperaminoaciduria, acidosis, uricosuria, proteinemia, progressive renal
insufficiency, and renal sodium and potassium wasting. Following the
diagnosis of renal tubular acidosis, an underlying cause should be sought
with appropriate investigations for inborn metabolic disease or
Excessive renal loss of glucose, amino acids,
potassium, bicarbonate, phosphate, calcium, water, and magnesium lead to
growth retardation/dwarfism, polyuria, polydipsia, metabolic
acidosis, muscle weakness, and rickets or osteomalacia (depending on age of onset). De
Toni Debré Fanconi syndrome can be the first manifestation of complex IV
Assess for dehydration and treat
accordingly. Detailed assessment of acid-base and serum electrolyte status
Patients are said to be particularly
anxious; consequently, sedative premedication is recommended. Patients have
ongoing polyuria and losses of bicarbonate, potassium, phosphate, calcium,
and magnesium, which require regular assessment and replacement. It may be
appropriate to monitor circulatory volume status during important surgical procedures with
the aid of central venous pressure monitoring or monitoring of left ventricular filling.
Careful positioning and handling are required because of
A case of hyperthermia under general
anesthesia in a patient with this syndrome secondary to cystinosis has been
reported. After the event, malignant hyperthermia was considered unlikely
and pyrexia, which developed during a subsequent nonmalignant
hyperthermia-triggering anesthetic, was treated successfully with
acetaminophen. Avoid drugs eliminated mainly by the renal system. Remember
that some drugs, such as certain antibiotics or neuromuscular relaxant
drugs, may require dosage adjustment. Succinylcholine is not contraindicated
except in the presence of hyperkaliemia. Uremic patients may be more
sensitive to the central depressant effect of benzodiazepines and opioids.
Those associated with renal