This is different from secondary hyperoxaluria, which is caused by the increase in dietary and intestinal absorption of oxalate or excessive intake of oxalate precursors.Oxalate stones in primary hyperoxaluria tend to be severe, resulting in relatively early kidney damage (in teenage years to early adulthood), which impairs the excretion of oxalate leading to a further acceleration in  accumulation of oxalate in the body.After the development of kidney failure patients may get deposits of oxalate in the bones, joints and bone marrow. Severe cases may develop haematological problems such as anaemia and thrombocytopaenia. The deposition of oxalate in the body is sometimes called "oxalosis" to be distinguished from "oxaluria" which refers to oxalate in the urine. Diagnosis
A diagnosis of primary hyperoxaluria is suspected based on presenting patient characteristics such as kidney stones in infants or children, recurrent kidney stones in adults, or family history of hyperoxaluria. In these patients, stone analysis and urine analysis are recommended to rule out secondary causes of hyperoxaluria. A definitive diagnosis of primary hyperoxaluria requires genetic testing. This is performed using a gene panel covering known mutations for all three types of primary hyperoxaluria. Classification
The three main types of primary hyperoxaluria (PH1, PH2, and PH3) are each associated with mutations in specific genes involved in the metabolism of glyoxylate, the precursor of oxalate. These mutations result in decreased production or activity of the proteins that are involved in the normal breakdown of glyoxylate, which results in an overproduction of oxalate.
Parakeratosis is a mode of keratinization characterized by the retention of nuclei in the stratum corneum. In mucous membranes, parakeratosis is normal. In the skin, this process leads to the abnormal replacement of annular squames with nucleated cells. Parakeratosis is associated with the thinning or loss of the granular layer and is usually seen in diseases of increased cell turnover, whether inflammatory or neoplastic. Parakeratosis is seen in the plaques of psoriasis and in dandruff. Granular parakeratosis (originally termed axillary granular parakeratosis) is an idiopathic, benign, nondisabling cutaneous disease that manifests with intertriginous erythematous, brown or red, scaly or keratotic papules and plaques. It presents in all age groups and has no established clinical associations. See also
Skin lesion
Skin disease
List of skin diseases


== References ==