Characteristics of cerebrospinal fluid in Guillain-Barré syndrome: In the first week after the onset of the disease, the characteristics of the cerebrospinal fluid are the same as normal, that is, the cerebrospinal fluid’s proteins, cells, and pressures are all within the normal range. After the second week the cerebrospinal fluid starts to have some changes, the protein may gradually rise and the cancer cell count is in the normal range. The most common clinical feature is protein-cell separation, and as the disease progresses, by the third week the cerebrospinal fluid is characterized by significant protein-cell separation, possibly with very high protein and white blood cells that are always in the normal range. Cerebrospinal fluid pressures in patients with this disease are within the normal range.