Primary hyperoxaluria II / PH2 / Oxalosis II (GRHPR-related) - Cat

Primary hyperoxaluria II in cats

This genetic test detects the GRHPR splice variant c.507-1G>A that causes primary hyperoxaluria type II. The condition is also known as PH2, Oxalosis II or GRHPR deficiency. Reduced glyoxylate reductase/hydroxypyruvate reductase activity creates excess oxalate, which can precipitate as calcium oxalate crystals in the kidneys.

Clinical picture and recognition

Affected kittens often develop kidney and urinary tract problems at a young age. Possible signs include acute renal failure, painful or abnormal kidneys, urinary stones, blood in the urine, weakness, dehydration and sometimes neurological or muscle-related signs.

Why this test is useful

• The test shows whether the cat is clear, a carrier or genetically affected for the tested GRHPR variant.
• Breeders can avoid carrier-to-carrier matings and strongly reduce the risk of affected kittens.
• The result supports targeted selection in breeds and lines where PH2 occurs.

PH2 is inherited as autosomal recessive: one copy means carrier status, while two copies cause primary hyperoxaluria II.