Autosomal recessive
Prolidase deficiency is caused by changes in both copies of PEPD, which makes prolidase, an enzyme that breaks down small protein fragments containing proline during collagen recycling.
Signs and symptoms
Chronic, painful skin ulcers, particularly on the lower legs and feet, are the most characteristic feature, often with other skin changes. Recurrent infections, especially of the skin, ears and respiratory tract, an enlarged spleen and distinctive facial features are common, and urine tests show large amounts of proline-containing dipeptides. Many have developmental delay or intellectual disability; less often there are autoimmune problems resembling lupus.
What a diagnosis changes
Care focuses on wound care for skin ulcers, prompt treatment of infections, and developmental support, with monitoring for autoimmune complications. Genetic counselling is recommended; parents are usually carriers, each future child has a 1 in 4 chance of being affected, and carrier testing can be offered to relatives.
Genes analysed
Also known as
hyperimidodipeptiduria; Imidodipeptidase deficiency; Peptidase deficiency
