Prevalence and Characteristics of Fabry Disease (FD) in Patients With Stroke or Small Fiber Neuropathy
Condition: Fabry Disease
MeSH terms: Fabry Disease; Small Fiber Neuropathy
Study type: Observational

Summary: 
      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).

      Aims will be to determine the prevalence of Fabry disease in patients with stroke or small
      fiber neuropathy, and their characteristics
    

Detailed description: 
      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).

        1. 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.

        2. 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.
    

Intervention name(s): Measurements of the alpha-GAL enzyme activity
Intervention type(s): Diagnostic Test
Intervention description(s): Blotting paper blood tests in order to highlight an enzyme deficiency for hemizygous males with DBS kits in order to detect Fabry disease, with genetic confirmation if an abnormality is detected. For women genotyping is mandatory.
Observational model: Case-Only
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Patients between 18 and 60 years old diagnosed with a TIA/ strocke or a SFN
      
Keywords: Fabry; Stroke; Cerebrovascular Accident; small fiber neuropathy