[Polymyositis and cranial neuropathy].

Background: Polymyositis with cranial neuropathy has been rarely reported.
Case Reports: We describe here three cases of polymyositis with trigeminal or facial neuropathy. Patients had muscular weakness, myalgia, rhabdomyolysis, endomysial infiltration with necrosis and regeneration at biopsy of muscle and, for two of them, a myopathic pattern at electromyogram. Two patients had also a Sjögren's syndrome and anti-nuclear antibodies. Anti-JO1 antibodies were presents in only one case. The outcome for one patient was good with corticosteroids alone. One other improved with the adjunction of immunoglobulin. The third one had a macrocheilia, a facial diplegia, antibodies against voltage-gated potassium channels and a neuromyotonia secondary to a paraneoplastic syndrome. He died after one year despite a treatment by corticosteroids and immunoglobulin. Patients fulfilled the diagnosis of polymyositis according to clinical, electromyographic, biological and histopathologic criteria. For the two patients with Sjögren's syndrome, the question of a primitive or a secondary Sjögren's syndrome remains unknown.
Conclusion: The occurrence of a cranial neuropathy in polymyositis should make us looking for an association with paraneoplastic syndrome or connective tissue disease.