primary hyperoxaluria type 3

What is Primary Hyperoxaluria Type 3?

Primary hyperoxaluria type 3 (PH3) is an inherited disease where lack of a particular liver enzyme causes the body to accumulate excess amounts of a substance called oxalate. Oxalate leads to a buildup of insoluble calcium salts in the kidneys. There are three types of primary hyperoxaluria. Unlike types 1 and 2, which can impact other organs, buildup of oxalate in PH3 has not been seen outside of the kidneys.

People with PH3 are at increased risk for developing kidney stones. Symptoms can develop anytime from infancy to adulthood. Approximately 50% of affected individuals developed kidney stones by age 5, but many experience a decrease by adulthood. Some people with the disease do not have symptoms until adulthood. Kidney function can be impacted by frequent kidney stones; however, kidney failure has rarely been reported in individuals with PH3.

How common is Primary Hyperoxaluria Type 3?

Approximately 1 in 165,000 individuals worldwide are expected to be affected with PH3. Reports of higher and lower carrier frequencies have been reported in the Ashkenazi Jewish and African American populations, respectively.

How is Primary Hyperoxaluria Type 3 treated?

People with the condition should drink plenty of water. Intravenous (IV) fluids may be necessary during periods of illness or times of limited fluid intake. A physician may prescribe medication or vitamins to help lower oxalate levels and inhibit the formation of kidney stones. Dietary restriction of foods high in oxalate may be beneficial. Unlike with other type of primary hyperoxaluria, individuals with PH3 rarely require dialysis or kidney/liver transplantation.

What is the prognosis for a person with Primary Hyperoxaluria Type 3?

Individuals with PH3 often have formation of multiple kidney stones, which can be managed by increased fluid intake and supplements. Kidney stone formation in many individuals with PH3 often decrease as they reach adulthood. Thus far, only one individual with PH3 has been reported to have progressed to kidney failure, and transplant is not necessary in most individuals with PH3.