Anxiety and aggressive behavior as initial presentation of neuronal ceroid lipofuscinosis in an Australian Shepherd dog: A case report

A 16-month-old, 20-kg intact female Australian shepherd dog was presented to a behavioral consultation for anxiety and aggression-related disorders. Physical examination and blood tests showed no health problems. A tailored behavioral and pharmacological treatment plan was initiated, which included clomipramine and behavioral modifications. However, after three weeks of treatment, the dog's clinical condition worsened, with increased anxiety, reluctance to move, and the emergence of oral ritualized, repetitive behaviors. This prompted a neurological examination, which revealed that the dog was lethargic, difficult to approach, disoriented, and blind. Based on these findings, a neurodegenerative disorder was suspected. Genetic testing subsequently confirmed a diagnosis of neuronal ceroid lipofuscinosis 6 (NCL6), a hereditary storage disorder known to occur in this breed. NCL6 is a storage disease comprised in a group of inherited, progressive neurodegenerative diseases characterized by accumulation of autofluorescent ceroid lipopigments in neurons and other cell types, including those in the retina. After few weeks the diagnosis, the dog was euthanized due to the rapid progression of the disease. Behavioral changes such as anxiety and aggression, particularly when followed by the onset of prosencephalic neurological signs, should prompt a neurological evaluation and, when available, genetic testing.