Hyperprolinemia type 2

Hyperprolinemia type 2 (also called HPI2 or delta-1-pyrroline-5-carboxylate dehydrogenase deficiency) is a rare inherited metabolic disorder. It happens when the body cannot properly break down an amino acid called proline. Amino acids are the building blocks of protein. In this condition, a specific enzyme called pyrroline-5-carboxylate dehydrogenase (P5CDh) does not work correctly, causing proline and a related compound called pyrroline-5-carboxylate (P5C) to build up in the blood and urine. Many people with hyperprolinemia type 2 have no symptoms at all and are discovered only through routine newborn screening or family testing. However, some individuals — especially children — may experience seizures or other neurological problems. The buildup of P5C is thought to interfere with vitamin B6 (pyridoxine) in the brain, which may explain why some patients have seizures that respond to vitamin B6 supplementation. Treatment is mainly focused on managing symptoms. There is no cure, but a low-protein or proline-restricted diet and vitamin B6 supplementation are the main approaches used. The overall outlook for most people with this condition is good, especially when it is identified early and managed carefully. Regular follow-up with a metabolic specialist is important.

Bring these to your next appointment

• Q1.Does my child (or I) need to follow a low-proline diet, and how strict does it need to be?,Should we try vitamin B6 supplementation, and what dose is safe?,How often should proline levels be checked in the blood and urine?,Are other family members at risk, and should they be tested?,What signs should prompt me to go to the emergency room?,Are there any clinical trials or research studies we could join?,What kind of school or developmental support might my child need?

Common questions about Hyperprolinemia type 2

Related conditions

Other rare diseases commonly researched alongside Hyperprolinemia type 2.

• Hyperprolinemia type 1→
• Prolidase deficiency→