Facial Dystonia with Facial Grimacing and Vertical Gaze Palsy with "Round the Houses" Sign in a 29-Year-Old Woman.

A 29-year-old woman developed progressive dysarthria and coordination problems from the age of 15. Examination showed dysarthria, facial dystonia, bibrachial dystonia, hyperreflexia, ataxia, and emotional incontinence. Downward supranuclear gaze palsy was prominent with a "Round the Houses" sign. Magnetic resonance imaging of the brain and medulla, electroneurography, and cerebrospinal fluid were normal. A computed tomography scan showed hepatosplenomegaly. This combination of progressive neurological symptoms together with hepatosplenomegaly was suggestive of inborn error of metabolism. A bone marrow biopsy showed an increased number of macrophages with foamy content, highly suggestive of lysosomal disease. Plasmatic chitotriosidase activity and CCL18 were increased. Genetic testing showed heterozygosis for the variation c.1070C→T (p.Ser357Leu) and c.1843→T (Arg615Cys), confirming the diagnosis of Niemann-Pick type C (NPC). The "Round the Houses" sign has only been described in patients with progressive supranuclear palsy (PSP). This sign is described as an inability to produce pure vertical saccades along the midline and instead moving the eyes in a lateral arc to accomplish the movement. The observation of this sign in a patient with NPC indicates that this bedside finding is not specific for PSP, but a sign of medial longitudinal fasciculus dysfunction. The presence of facial dystonia with facial grimacing together with supranuclear gaze palsy is highly characteristic and useful for the diagnosis of NPC. NPC is an important underdiagnosed condition, given the availability of treatment and a mean diagnostic delay of 6 years.