LAENALS: epidemiological and clinical features of amyotrophic lateral sclerosis in Latin America.

OBJECTIVE: The Latin American Epidemiologic study of ALS (LAENALS) aims to gather data on ALS epidemiology, phenotype, and risk factors in Cuba, Chile, and Uruguay, to understand the impact of genetic and environmental factors on ALS. METHODS: A harmonized data collection protocol was generated, and a Latin-American Spanish language Register was constructed. Patient data were collected in Uruguay in 2018, in Chile from 2017 to 2019, and in Cuba between 2017 and 2018. Statistical analysis was performed using SPSS 25.0.0 software. Crude cumulative incidence, standardized incidence, and prevalence were calculated in the population aged 15 years and older. RESULTS: During 2017-2019, 90 people with ALS from Uruguay (55.6% men), 219 from Chile (54.6% men), and 49 from Cuba (55.1% men) were included. The cumulative crude incidence in 2018 was 1.73/100,000 persons in Uruguay, 1.08 in Chile and 0.195 in Cuba. Crude prevalence in 2018 was 2.19 per 100,000 persons in Uruguay, 1.39 in Chile and 0.55 in Cuba. Mean age at onset was 61.8 ± 11.96 SD years in Uruguay, 61.9 ± 10.4 SD years in Chile, and 60.21 ± 12.45 SD years in Cuba (p = 0.75). Median survival from onset was 32.43 months (21.93 - 42.36) in Uruguay, 24 months (13.5 - 33.5) in Chile, and 29 months (15 - 42.5) in Cuba (p = 0.006). CONCLUSIONS: These preliminary data from LAENALS confirm the lower incidence and prevalence of ALS in counties with admixed populations. The LAENALS database is now open to other Latin American countries for harmonized prospective data collection.

Enfermedad de hirayama en un adolescente / Hirayama disease observed in an adolescent

La Enfermedad de Hirayama -o amiotrofia monomélica- es una afección de baja frecuencia y escasamente reportada en la edad pediátrica. Se presenta el caso clínico de un adolescente de 15 años de edad con disminución de la fuerza muscular y pérdida de la masa muscular, que comenzó a los 10 años de edad por la mano izquierda, y le afectó posteriormente el antebrazo. Mantuvo un curso progresivo durante 3 años, para luego mantenerse estable. El electromiograma de aguja arrojó lesión de axones motores o motoneuronas dependientes de los miotomas C7-T1, y en menor grado, C5-C6. En la tomografía axial computarizada con contraste endovenoso en marcada flexión cervical, se observó desde C7-T2 una evidente ectasia venosa posmedular asimétrica, predominantemente del lado izquierdo, por congestión del plexo venoso vertebral posterior interno. En este paciente la enfermedad se detuvo espontáneamente, en otros casos es necesario limitar la motilidad de la columna con el uso de un collar cervical, y solo llegar a la cirugía en los casos más severos de evolución rápida.

Hirayama disease or monomelic amyotrophy is a low frequent, barely reported illness at pediatric ages. Here is the clinical case of 15 years-old boy that presented with reduced muscular strength and loss of muscle mass; this condition began at the age of 10 year in his left hand and then affected the forearm. The illness progressed for three years and then remained stable. The needle electromyogram showed a lesion in C7-T1 myotome-depending motor axons or motoneurons and to less extent in those C5-C6 depending ones. The venous contrast computed tomography on a marked cervical cord flexion position; it was observed an evident asymmetric postmedullary vein ectasia from the C7-T2 myotomes, mainly on the left side, caused by the internal posterior vertebral vein plexus congestion. There was spontaneous remission of the disease in this patient, but it is necessary in other cases to limit the cervical cord motility with the use of a collar and to only perform surgery in the most rapidly evolving and severe cases.