Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† nephrītis, ĭdis, f., = νεφρῖτις, disease of the kidneys, nephritis [pure Lat.: renalis passio, renale vitium]: nephritis a renum languore nomen accepit: renes enim Graeci νεφρούς dicunt, Isid. Orig, 4, 7, 24.
Hence, nephrītĭcus, a, um, adj., affected with nephritis, Cael. Aur. Tard. 5, 1, 6.