Spinal muscular amyotrophy of lower limb predominance - SMALED1: case report

Case presentation: Male patient, 1 year-old, born and resident in Maranhão. Mother reported reduced fetal movement, after birth some dysmorphisms were identified such as deformity in the lower limbs, characterized by arthrogryposis, bilateral congenital clubfoot, bilateral congenital dislocation of the hip and fracture of the right femur perceived on the fifth day of life. During development, generalized hypotonia and significant motor delay were noticed, predominantly affecting the lower limbs. The evaluation identified blue sclera, hyperelasticity mainly of the upper limbs, batrachian posture, osteotendinous and plantar cutaneous reflexes not obtained, bilateral congenital clubfoot, without apparent sensory and cranial nerve changes. A complementary workup was performed with the collection of a panel for neuromuscular diseases with evidence of a mutation in the DYNC1H1 gene, indicative of Predominant Lower Limb Spinal Muscular Amyotrophy (SMALED1) of autosomal dominant inheritance.