Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease that may occur in a postvaccination condition or as a parainfectious encephalomyelitis. It is almost always monophasic. The underlying pathogenesis of ADEM may include perivascular inflammation, oedema and demyelination in the central nervous system. We present a case of a 15-year-old girl who was diagnosed as having ADEM, as well as detected to be a follow-up case of autoimmune haemolytic anaemia on steroid treatment. She presented with progressive weakness of the right lower limb for the past 4 days. MRI showed multiple subcortical lesions of varying size showing hyperintensities in T2 fluid-attenuated inversion recovery (FLAIR). The patient responded well to steroid therapy. No residual lesion was found on follow-up. Very few cases have been found with this rare association in the literature.