GRHPR and primary hyperoxaluria: Primary Hyperoxaluria encompasses three types, all autosomal recessive: Type 1 results from alanine-glyoxylate aminotransferase (AGT) deficiency, Type 2 involves glyoxylate reductase hydroxypyruvate reductase (GRHPR) deficiency, and Type 3 stems from 4-hydroxy-2-oxoglutarate aldolase (HOGA) deficiency [15].