1. Diagnosis of PH established by liver enzyme analysis in the patient or an affected sibling, DNA testing for mutations of the AGXT and GR/HPR gene, or meeting clinical criteria (Urine oxalate > 70 mg/1.73 m2/day in the absence of malabsorption or dietary excess of oxalate. Elevated urine glycolate or glycerate provides supporting evidence of type I or type II PH, respectively).