ESPE Abstracts

Introduction: Homocystinuria due to cystathionine-beta-synthase (CBS) deficiency is a rare abnormality of methionine catabolism. The diagnosis is suspected on the increase in plasma total homocysteine (Hcyt) and plasma methionine (Met). The diagnosis is confirmed by looking for bi allelic mutations in the CBS gene.

Observation: A 14-year-old boy from a consanguineous marriage with no history. 48 hours before his admission, he presented 02 episodes of convulsions in an afebrile context. The clinical examination revealed a disturbed neurological examination: drowsiness, motor aphasia, left facial paralysis, paralysis of the left 6th cranial pair and left hemiplegia. Furthermore, a marfanoid appearance was noted. Brain CT came back in favor of venous thrombosis (VT) of the sagittal sinus complicated by an edematous-hemorrhagic infarction. We note hyper-Hcyt at 340 μmol/L, homocystinuria at 140 μmol/L with a high level of (Met). The rest of the assessment was normal, notably the vitamin dosage.

Discussion: Patients with CBS deficiency present a spectrum of clinical manifestations, ranging from asymptomatic to severe forms with multi-system involvement. The most common symptoms essentially affect 4 types of organs: the eye, the brain, the bone and the vascular system. The phenotype and severity of the disease are essentially defined by the degree of response of the CBS deficiency to vitamin B6 which is the cofactor of the CBS enzyme. It is established in the literature that early diagnosis and treatment make it possible to avoid the usual complications of the disease, if compliance with treatment is good. Interest in neonatal screening.

Conclusion: The Hcyt dosage must be part of the thrombophilia assessment with a genetic analysis when faced with a picture of unusual thrombosis at an unusual site in a young subject. Management of VT often involves long-term anticoagulant treatment to prevent further thromboses.