Progressive encephalomyelitis with rigidity and myoclonus: a case report / 中华神经科杂志

ABSTRACT

Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a specific subtype of the stiff-person syndrome, which is rare and difficult to diagnose clinically. A case of PERM in a 66-year-old female with a fluctuating progressive course was reported in this article. She had increased facial muscle tone, pruritus and sensory hypersensitivity mainly in the head and neck, medullary involvement syndrome and bilateral lower limb rigidity as the main clinical manifestations, and a previous history of pulmonary malignancy, thymoma, typeⅠ diabetes and Hashimoto′s thyroiditis. The patient′s serum and cerebrospinal fluid were positive for anti-glutamic acid decarboxylase antibody. The electromyogram showed a large number of motor unit potentials in the trunk and proximal extremities in the quiet state, which were significantly enhanced during spastic episodes, consistent with the electromyographic manifestations of stiff-person syndrome. The final diagnosis was PERM, and immunotherapy including gamma globulin and hormone responded well. PERM is a rare neurological autoimmune disease with atypical early symptoms, which can be easily misdiagnosed, and it requires attention to avoid delaying the diagnosis.