Hyperoxaluria, Primary, Type I

Background and History: 

This is an inherited disorder of metabolism in which a malfunctioning enzyme leads to an accumulation of crystals of oxalate in tissues. 

Clinical Correlations: 

Oxalate crystals are deposited throughout the body beginning in infancy.  Failure to grow can be seen in youngsters within a few months of age although this occurs in only a small proportion.  More often, young children and adolescents show signs of kidney damage with the formation of stones.  Crystals may also cause blood vessel disease, damage to the light sensing tissue of the eye (retina), and to the heart causing an abnormal heart beat.  Damage to the retina can lead to severe loss of vision.  Damage to nerves often occurs as well.  In fact, the crystals deposit throughout all tissues of the body causing a variety of illnesses. 


This is an autosomal recessive disorder caused by the presence of two mutations in a gene.  The healthy carrier parents each contribute a single mutation and, on average, they can expect that one in four of their children will inherit the two mutations. 

Diagnosis and Prognosis: 

A pediatrician is likely to make the diagnosis based on chemical studies of the urine or maybe a biopsy of tissue.  Neurologists and ophthalmologists may collaborate on the diagnosis.  Left untreated, the kidneys often fail and many individuals die relatively young.  Oral doses of pyridoxine (B6) can be therapeutic but should only be used under supervision for certain doses can by themselves also cause damage to tissue, especially nerves.  Patients should also drink plenty of water.  A combination of liver and kidney transplants can also be life-saving.  Thus, while treatments are available, they must be carefully monitored for a lifetime. 

Additional Information