Content sponsored by Alnylam Pharmaceuticals, Inc.

Primary hyperoxaluria type 1, or PH1, is a rare life-threatening disease that impacts the kidneys. PH1 is caused by a genetic deficiency in a liver enzyme involved in glyoxylate metabolism, leading to overproduction of oxalate – an insoluble metabolite responsible for the pathophysiology of the disease. Excess oxalate combines with calcium and creates calcium oxalate crystals; these are deposited in the kidneys and urinary tract and can lead to the formation of painful and recurrent kidney stones – the most common symptom of the disease – nephrocalcinosis, progression to end-stage kidney disease, and multiorgan damage.

Diagnosis and management early in disease course can mitigate damage. Elevated oxalate levels in a 24-hour urine test should raise suspicion of PH1, with genetic testing helping to confirm a diagnosis. Thus, once suspected, diagnosing PH1 can be straightforward.

Any unusual presentation among stone formers, such as any child or adolescent with a kidney stone or adults with recurrent kidney stones, merits further investigation.

In this video, learn more about the clinical manifestations of PH1, its downstream impact on multiple organ systems and diagnostic approaches, including the importance of genetic testing.

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