Necrotizing myopathies can be encountered in acquired myopathies or muscular dystrophies.
The clinical presentation of our patient was initially suggestive of an inflammatory myopathy.
She presented significant but partial clinical improvement after corticosteroid and immune therapies.
Additional investigations finally led to a diagnosis of limb-girdle muscular dystrophy 2I.
This observation highlights diagnostic difficulties and implications of corticosteroid treatment in patients with LGMD2I.