title: Downbeat nystagmus secondary to familial hemophagocytic lymphohistiocytosis.
abstract: Hemophagocytic lymphohistiocytosis is a rare autosomal recessive disorder characterized by severe inflammation induced by defective natural killer cell function, which triggers a state of highly stimulated but ineffective immune response. This disorder can affect multiple organ systems, and neurologic manifestations include irritability, seizures, impaired consciousness, meningismus, and cranial nerve palsies. We describe a unique case of hemophagocytic lymphohistiocytosis in which downbeat nystagmus developed due to cerebellar swelling with compression of the cervicomedullary junction.
authors.affiliation: Columbia University College of Physicians and Surgeons (CXC), New York, New York; Departments of Ophthalmology (FSS, JGO), Radiology (AL), and Pathology (TG); Columbia University Medical Center, New York Presbyterian Hospital, New York, New York; and Department of Clinical Immunology (AHF), Cincinnati Children's Hospital, University of Cincinnati, Cincinnati, Ohio.
authors.forename: Cindy X
authors.initials: CX
authors.lastname: Cai
authors.forename: Frank S
authors.initials: FS
authors.lastname: Siringo
authors.forename: Jeffrey G
authors.initials: JG
authors.lastname: Odel
authors.forename: Angela
authors.initials: A
authors.lastname: Lignelli-Dipple
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Lanzman
authors.forename: Tatyana
authors.initials: T
authors.lastname: Gindin
authors.forename: Alexandra H
authors.initials: AH
authors.lastname: Filipovich
mesh_terms: D001706:Biopsy; D001853:Bone Marrow / Q000473:pathology*; D001921:Brain / Q000473:pathology*; D003937:Diagnosis, Differential; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D051359:Lymphohistiocytosis, Hemophagocytic / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D009759:Nystagmus, Pathologic / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology