Acute hydrocephalus resulting from neuromyelitis optica: A case report and review of the literature

Background Neuromyelitis optica is an autoimmune disorder of the central nervous system that predominantly affects the optic nerves and spinal cord. The neuropathologic hallmark of the disease is deposits of antibodies and complement, loss of astrocytes, secondary degeneration of oligodendrocytes and neurons, and necrotic lesions with infiltration of neutrophilic and eosinophilic granulocytes. It can rarely be associated with hydrocephalus, but the cause and mechanisms that result in hydrocephalus are not clear. Case Description A 35-year-old woman with a history of neuromyelitis optica presented with a 5-day history of progressively worsening lethargy, fatigue, somnolence, and headaches. Imaging demonstrated new hydrocephalus without evidence of obstruction, and extensive periventricular enhancement concerning for active demyelination. She underwent placement of a ventriculostomy, and subsequently underwent endoscopic biopsy and ventriculoperitoneal shunt placement. Pathology confirmed demyelination secondary to neuromyelitis optica. Conclusions This case provides evidence of the rapid development of hydrocephalus in association with periventricular inflammation, without aqueductal stenosis. In a state of aquaporin-4 dysfunction such as in neuromyelitis optica, altered cerebrospinal fluid resorption could lead to acute hydrocephalus by a nonobstructive mechanism.