We examined progranulin (PGRN) levels in cerebrospinal fluid (CSF) samples during the acute phase in 15 patients with neuromyelitis optica spectrum disorders (NMOSD) and compared the results with those from 17 patients with multiple sclerosis (MS), 30 patients with other inflammatory neurological diseases (OIND), and 20 non-inflammatory controls (NIC). CSF PGRN levels of NMOSD patients were significantly higher than those of MS patients and NICs. These levels correlated with CSF interleukin-6 levels, CSF cell counts, CSF protein levels, improvements in the Expanded Disability Status Scale score, and affected total spinal cord lesion length in the NMOSD patients. (C) 2017 Elsevier B.V. All rights reserved.