Mayo Clinic researchers have used pharmacogenomics to develop a test and treatment for an inherited kidney disorder that can cause organ failure in children and young adults.
The findings appear in the current issue of the journal Kidney International. Pharmacogenomics tailors treatment to an individual's genetic makeup to maximize the therapeutic response.
Early diagnosis is important, as the condition -- type I primary hyperoxaluria -- if not treated early and correctly, can cause kidney stones or kidney failure and necessitate a transplant. The researchers discovered that a genetic mutation allows certain kidney stone patients -- many of them children -- to benefit from vitamin B6, and have used the finding to develop a genetic test to predict which patients are best suited for this treatment.
In discovering the link between a specific mutation and vitamin B6 responsiveness, the Mayo Clinic researchers can now use a genetic test for guiding treatment to maximize the probability of swift, successful treatment for select cases of type I primary hyperoxaluria. The disease is uncommon, but if left undiagnosed and untreated, at least half of those affected will suffer kidney failure. Patients most often develop the first symptoms -- usually kidney stones -- during infancy or childhood. However, the disorder may go unrecognized until age 30 to 40. In some cases the first symptom is kidney failure.
The gene defect responsible for the disorder disrupts production of a key enzyme located in the liver, and this enzymatic deficit then allows the liver to produce too much oxalate, which is excreted in the urine. High concentrations of oxalate in the urine can cause kidney stones and injury to the kidney, leading to kidney failure.