Evaluación de pacientes con enfermedad de Fabry en la Argentina / Evaluation of patients with Fabry disease in Argentina

La enfermedad de Fabry es un desorden lisosomal de transmisión ligada al cromosoma X debida al déficit de la enzima alfa galactosidasa A, con acumulación multisistémica de globotriaosilceramida y compromiso neurológico, gastrointestinal, cardíaco, renal, dermatológico y oftalmológico. Estudios recientes indican que las mujeres heterocigotas desarrollan síntomas similares a los de los varones, pero no existen en nuestro país datos comparativos respecto de la frecuencia relativa de manifestaciones clínicas, edad de inicio y gravedad entre hombres y mujeres con enfermedad de Fabry. Identificamos 59 pacientes adultos sintomáticos con enfermedad de Fabry: 32 varones (edad media: 34.8 años) y 27 mujeres (edad media: 46.6 años). El diagnóstico se hizo por estudios enzimáticos en los hombres y genéticos en las mujeres. Se evaluó la frecuencia y la gravedad de las manifestaciones de la enfermedad. Las manifestaciones más frecuentes fueron acroparestesias, angioqueratomas, hipohidrosis y córnea verticilada; las tres primeras fueron estadísticamente más frecuentes en hombres, en los cuales la gravedad de estos síntomas fue significativamente mayor. Proteinuria e hipertrofia ventricular izquierda fueron hallazgos frecuentes tanto en hombres como en mujeres. Hubo una latencia prolongada entre la edad del inicio y la del diagnóstico de 14 años para varones y 30 para mujeres. La enfermedad de Fabry es una enfermedad subdiagnosticada y potencialmente letal que afecta a ambos sexos. La existencia de reemplazo enzimático obliga a identificar precozmente los síntomas y signos sugestivos de la enfermedad para realizar un diagnóstico y tratamiento precoces.

Fabry disease is an X- linked lysosomal disorder due to deficient activity of the enzyme alpha galactosidase A which leads to multisystemic storage of globotriaosylceramide with neurologic, gastrointestinal, cardiac, renal, skin and ophtalmological involvement. Recent studies indicate that heterozygous females develop symptoms similar to the males, but comparative information regarding the relative frequency of clinical manifestations, age of onset and severity of the disorder between males and females with Fabry disease is not available in Argentina. We identified 59 symptomatic adult patients with Fabry disease: 32 males (mean age 34.8 years) and 27 females (mean age 46.6 years). Diagnosis was made by enzymatic analysis in males and by genetic studies in females. We compared the frequency and severity of the clinical manifestations in females and males with this disease. The most frequent manifestations were: acroparesthesias, angiokeratomas, hypohydrosis (all them were significantly more frequent in males than in females, as well as the severity of symptoms), and cornea verticillata. Proteinuria and ventricular hypertrophy were frequent findings both in males and females. There was a delayed latency between age at onset and age at diagnosis in our group: 14 years for men and 30 years for females. Fabry disease is an underdiagnosed and potentially fatal disorder that affects both sexes. The availability of enzyme replacement therapy should stimulate the identification of signs and symptoms suggestive of this disorder, to allow earlier diagnosis and treatment.

Clinical and molecular characterization of an extended family with Fabry disease.

OBJECTIVE: To characterize clinical manifestations, biochemical changes, mutation of alpha-Galactosidase (alpha-Gal A) gene A (GLA), and functional capability of mutant protein. MATERIAL AND METHOD: Seventeen subjects from a family with a newly diagnosed patient with Fabry disease were enrolled in the present study. In each individual, clinical history, physical examination, leukocyte enzyme activity of alpha-Gal A, and mutation analysis were performed. Those with a mutation were further investigated by ophthalmological and audiological evaluations, electrocardiography, echocardiogram, urinalysis, and blood tests to determine renal insufficiency. Expression study of the mutant protein was performed using a Pichia pastoris expression system. RESULTS: Four affected males and five symptomatic female carriers were identified. Clinical manifestations included severe neuropathic pain, acroparesthesia, hypo-/hyper-hidrosis, frequent syncope, ischemic stroke, cardiac hypertrophy, corneal dystrophy and cart-wheel cataract, high frequency sensorineural hearing loss, periorbital edema and subcutaneous edema over hands and interphalangeal joints. None had angiokeratoma or renal symptoms. The authors identified a novel mutation, p.L106R, in the GLA gene. Recombinant expression of the mutant protein gave little or no enzyme activity compared to the normal protein. CONCLUSION: There were intrafamilial clinical variabilities, but consistent findings of the absence of angiokeratoma and renal symptoms, which could represent a unique feature of this particular mutation.