Prevalence and Characteristics of Fabry Disease (FD) in Patients With Stroke or Small Fiber Neuropathy

FD is pan-ethnic. Its reported annual incidence of 1 in 100,000 may underestimate the true prevalence of the disease. Indeed, recently, in addition with affected males FD developing a "classic" phenotype, " cardiac variant " and " renal variant " have been reported for FD patients with predominant or exclusive cardiac or renal involvement. " Neurologic variant " could exist.

Nervous system can be affect by FD leading to cerebrovascular diseases (ischemic or haemorrhagic strokes, TIA (Transient Ischemic Attacks) or peripheral neuropathy (acroparesthesias and pain).

• Considering strokes, they are the third leading cause of death in France, with more than 140,000 people presenting a stroke per year. Stroke incidence is 1-2/1000 people per year. If the mean age of stroke patient is 72 yo, 25% of them are under 55 yo. The etiology of stroke in young patients remains undetermined in up to half of the cases. Data on prevalence of FD in people with cryptogenic ischaemic stroke are limited and controversial. In addition to cryptogenic strokes, FD can lead to stroke from arterial or heart diseases (secondary to high blood pressure, renal insufficiency, cardiomyopathy, rate variability, arrhythmias, valvular insufficiency).

The investigators aimed to evaluate the frequency of FD in a cohort of stroke patients in tertiary stroke centers in consecutively recruited patients under 60 yo. The investigators will include patients with so-called cryptogenic stroke but also stroke patients due to large artery atherosclerosis, cardioembolism, and small-vessel occlusion. The investigators will also study the clinical and radiological characteristic of stroke patients due to FD, and will compare these data with those from patients without FD, supported by biochemical and genetic findings.

• Considering peripheral nervous system, Small fiber neuropathy (SFN) is a subgroup of peripheral neuropathy which is characterized by an affection of the thin myelinated A-δ and unmyelinated C-fibers. SFN patients present with sensory symptoms and pain. SFN are not a rare condition; recent study showed a minimum prevalence of 50/100.000. The most commonly etiology reported for SFN is diabetes mellitus ; Other possible etiologies include connective tissue disease, celiac disease, thyroid dysfunction, vitamin B12 deficiency, monoclonal gammopathy, HIV and hepatitis C infections, amyloidosis, toxicity due to alcohol or drugs, and hereditary neuropathies including FD, suspected to be underdiagnosed.

In SFN patients,the investigators aimed to screen for FD in our tertiary national center for peripheral neuropathies, in addition to others diseases or affections, to evaluate the frequency of FD in a large cohort of SFN patients, and describe the clinical phenotype of SFN in FD patients compared to other ones.

Inclusion criteria

• patient over 18 yo and under 60 yo
• diagnosed with a TIA / stroke (ischemic and haemorrhagic strokes) based on clinical evaluation and MRI
• diagnosed with small fibers neuropathy (SFN) with normal nerve conduction studies in conventional electrophysiology

Exclusion criteria

• patients over 60 yo