Primary hyperoxaluria type 2 (PH2) is an inherited disorder that is caused by the deficiency of an enzyme named glyoxylate reductase/hydroxypyruvate reductase (GR/HPR). People with PH2 have excessive accumulation of insoluble calcium salts in various tissues of the body, especially the kidney. PH2 causes recurrent kidney stones, which, if untreated, can cause life-threatening kidney failure. Age of onset of symptoms is typically in childhood. Affected individuals may also experience problems in their bones, eyes and heart due to the accumulation of calcium salts in these tissues. Intellect is not affected by PH2. There is no cure for PH2. People with this condition need to drink plenty of water and take medications to minimize kidney injury. Kidney transplantation may be needed at the time of kidney failure. PH2 is caused by pathogenic variants in the GRHPR gene.