Ocular And Thromboembolic Manifestations Revealing Homocystinuria: A Case Report

To present an extremely rare case of Homocystinuria which is a genetic metabolic disorder characterized by the presence of an abnormal amino acid, homocystine, in the blood and urine. This condition is primarily characterized by ocular involvement (lens ectopia, myopia), skeletal issues, central nervous system involvement, and vascular accidents.

EPH HAKIM OKBI, GUELMA, ALGERIA

A 10-year-old girl was referred to our department for poor vision. The clinical examination revealed a long-limbed body type (Marfanoid), bilateral lens ectopia, severe myopia, a history of ischemic stroke at the age of 8, and parental consanguinity. 

A plasma homocysteine level was requested and showed:
Plasma homocysteine = 160 µmol/l [normal <10 µmol/l]

The assessment was completed with a plasma and urinary amino acid test, which revealed:
An elevation of plasma homocysteine
An elevation of plasma methionine
A significant increase in urinary homocysteine

This biological profile supports the diagnosis of homocystinuria due to cystathionine beta-synthase deficiency

It is important to request a blood homocystine level in any young patient presenting lens dislocation and/or an occlusive vascular accident.

One of the priorities in managing lens ectopia is to diagnose an associated systemic disease that could be mortal