AQP4 and oculocutaneous albinism type 1: With respect to the other CSF proteins analysed in 101 of these patients using CLEIA method, considering the differences in AQP4 concentrations with respect to the ATN classification criteria, AQP4 levels were significantly higher in the N+ group, which is defined by the total Tau concentration in CSF (Mann–Whitney test: A + vs A − p = 0.202, T + vs T − p = 0.622, N + vs N − p = 0.004) (Fig. 3).