Medically reviewed by Dr. Shani Saks, D.O. on Sept. 3, 2023 A recent study reveals the potential of granulocyte activation markers in cerebrospinal fluid as a reliable biomarker for distinguishing neuromyelitis optica spectrum disorder from multiple sclerosis, even when the gold-standard diagnostic biomarker, anti-aquaporin-4 protein antibodies, is negative. Granulocyte activation marker levels in cerebrospinal fluid can...