Prolidase Deficiency

A rare congenital disorder of the small peptides metabolism (imidazoles dipeptides). It is characterized by mild to severe skin lesions affecting mostly the face, palms, lower legs, and soles. These recalcitrant ulcerations respond partially to treatment and steroids.

Imidodipeptidase; Peptidase D; Proline Dipeptidase.

Autosomal recessive; the PEPD gene maps to chromosome 19p13.2; prolidase deficiency seems to be a risk factor for the development of systemic lupus erythematosus.

The deficiency in exopeptidase prolidase (or peptidase C) produces massive excretion of imidopeptides (i.e., dipeptides with a proline or hydroxyproline N-terminal).

Hyperiminopeptiduria; low or absent prolidase activity in leukocytes or fibroblasts.

First symptoms appear between birth and 22 years of age; prognosis, age of onset, and severity of the lesions are highly variable: skin lesions: rash with diffuse telangiectasia, ecchymosis, difficult to cure leg ulcers; characteristic facies: prominent skull sutures, ptosis and proptosis; recurrent infections of the skin, chronic ear and sinus infections; impaired motor or cognitive development may be present. Treatment: oral ascorbate or manganese is useful for the treatment of skin lesions.

Presence of foci of chronic infection.

Careful positioning because of fragile skin and the presence of ulcers.

There are no known pharmacological implications.