Neurological signs and imaging findings in two American Staffordshire Terrier dogs diagnosed with neuronal ceroid lipofuscinosis 4A: First report of the presenceof the ARSG gene mutation in Brazil

Sinais neurológicos e achados de imagem em dois cães American Staffordshire Terrier diagnosticados com lipofuscinose ceroide neuronal 4A: Primeiro relato da presença da mutação no gene ARSG no Brasil

Neuronal ceroid lipofuscinosis 4A (NCL4A) is a rare hereditary neurodegenerative disease that affects adult American Staffordshire Terriers (AST) leading to progressive late onset signs of typical cerebellar deficits. We report for the first time in Brazil, the presence of the causative mutation for NCL4A in the ARSG gene in two AST, the neurological signs and imaging findings. Both dogs were presented with a late onset progressive cerebellar deficits. Magnetic resonance imaging scan (MRI) and cerebrospinal fluid analysis were performed in both cases at the initial clinical course and no abnormalities were found. One dog was submitted to a new MRI three years later and cerebellar atrophy was evident. Both dogs were tested for the causative mutation for NCL4A in the ARSG gene and were both positive. NCL4A should be considered the main differential diagnosis in an adult AST presenting a late onset progressive cerebellar deficits. Cerebellar atrophy on MRI scan reinforces the suspicion, but confirmation of the causative genetic mutation in the ARSG gene remains the gold standard antemortem diagnosis for NCL4A in the AST.

Key words:
hereditary ataxia; lysosomal storage disease; NCL4A; cerebellar atrophy; American Staffordshire Terrier