Recherche de thrombophilie dans le bilan étiologique de l’infarctus cérébral artériel du sujet jeune : l’expérience du Centre Hospitalier de Perpignan

Abstract

Stroke incidence of people aged under 55 years is about
34/100 000 and 30 to 35% of strokes occurring in young
people are unexplained after complete investigations. The prothrombotic states role is not recognized in arterial brain
diseases. In this study based on prospective collected data,
we proposed to include the coagulation disorders screening
in the arterial stroke etiologic investigations of young
people aged under 55. We undertook this study to identify
which coagulation screening is justified and groups of
patients whom should have those biologic assessments.
Patients and method: 84 patients were prospectively
evaluated in the stroke unit of Saint Jean’s Perpignan
Hospital, between the 1st of January 2006 and the 31st of
December 2007. All patients underwent coagulation disturbances screening including: hyperhomocysteinemia, C677T
mutation of methylene tetra hydrofolate reductase
(MTHFR), protein S (PS), protein C (PC) and antithrombin III
(AT III) deficiencies, activated protein C resistance (RPCa),
Leiden factor V mutation, G20210A prothrombin gene
variant and anti-phospholipid antibodies (aPL) (lupus anticoagulant (LA), anticardiolipin antibodies (aCL) and antibeta2-glycoprotein 1 (anti b2 GP1)).
Results: 1 protein C deficiency, 2 protein S and 1 AT III
deficiencies were discovered (only one real PS deficiency
excluding the secondary deficiencies and the non confirmed
abnormalities, and only one AT III deficiency related to dysimmunitary disease), 10 mild to moderate hyperhomocysteinemias. Anti-phospholipid antibodies prevalence was
lower than these found in literature with only 3 patients: 2
patients with aCL (63 tested patients (3,2 %): one systemic
lupus and one Raynaud’s syndrome), and 1 with LA (with an
essential thrombocythemia) on 45 tested patients (2,2%).
We determined only one patient with the G20210A prothrombin gene variant (heterozygous) with many others
vascular risk factors. 24 patients were heterozygous for the
C677T MTHFR mutation and 9 were homozygous. No activated PC resistance or Leiden factor V were diagnosed (only
4 patients tested for this mutation). All those results were
compared to literature. Our results suggest a FOP and
MTHFR mutation relation: MTHFR mutation frequency is
about 87,5% for patients with FOP (7 of 8 patients) against
53,1% for the population without FOP (17 of 32). However,
the significance threshold is not reached: X2 Pearson test
=3,77, p=0,052.
Conclusion: Hyperhomocysteinemia screening must be
proposed to young people suffering from arterial ischemic
stroke (vitamin deficiency correction). MTHFR mutation
research could be restricted to high hyperhomocysteinemia,
vitamin deficiency excluding. PC, PS and ATIII deficiencies
must only be investigated in specific clinical cases.
Antiphospholipid antibodies screening must be directed by
clinical, biological and historical arguments. RCPa and
G20210A prothrombin gene variant search shall not be
included in etiological assessment of arterial stroke in
young people excepted for paradoxical embolisms.