Neuromyotonia (Isaacs’ Syndrome) In A Patient With Shistosomaiasis With Good Response To Plasmapharesis: A Case Report

摘要

Isaacs’ syndrome is a rare disorder characterized by hyperexcitability of peripheral motor nerves. The cardinal features consist of myokymia, pseudomyotonia and contracture of hands and feet. The diagnosis of Isaacs’ syndrome is based on the clinical features and classic electromyographic findings. Serum antibodies against Voltage-Gated Potassium Channels (VGKCs) are detected in some cases. Our 61 years old patient presented with generalized stiffness , more in the upper limbs associated with fasciculations , muscle cramps , carpopedal spasm and attacks of sweating. Patient also reported parathesia of both hands . Muscles were in a state of contraction,myokymia and carpopedal spasm with no clinical myotonia. Electromyography showed classical neuromyotonic and myokymic discharges. The investigations for conditions associated with Isaacs’ syndrome were done excluding most of the causes.Association between Shistosomiasis and Isaac's syndrome is rare,yet reported in literature. VGKCs antibody were not performed. Treatment with Plasmapharesis resulted in substantial improvement of the symptoms. Case Report A 61 years old male patient, farmer from Abo Humos , married with 7 offspring, presented with subacute onset, progressive course of painful spasms of the right upper limb since 1 year ( Distal more than proximal ) with no precipitating factor that progressed to stiffness of the right upper limb. The condition progressed to involve the left upper limb within 3 months in the form of stiffness and frequent spasms followed by the trunk and the paraspinal muscles, and lastly the lower limbs were affected since 4 month.The patient developed fasciculations through the course of the illness. It was generalized, spontaneous and involving the eyelids, face, upper and lower limb. Recurrent attacks of muscle cramps were of daily frequency mainly involving the upper limbs. Increase sweating was also reported by the patient. He complained of mild paraesthesia involving both upper limbs. No bulbar, sphincteric or cognitive manifestations and no constitutional manifestations or weight loss was seen. No past history of DM or hypertension was found. The patient hada history of Bilharziasis since 50 years, for which he received tartar emetic. The patient had also a history of oral lesions since 5 years that recurred after surgical intervention. Family History and Drug History were negative.General examination revealed average body built with stiffness of both hands (Fig 1). Consciousness and MSE were normal. Head and Neck examination was normal except for a submandibular lymph node . Gait was in short steps due to stiffness of the lower limb. Speech and articulation were normal. Cranial nerve examination only showed tongue wasting and fasciculations. Motor examination revealed average muscle status with no wasting. Stiffness all over more in the upper limbs and more distally was found. There was no weakness and the patient showed spontaneous gross fasciculations in both upper and lower limbs and in the face over the masseter muscle and around the eye. Sensory examination revealed short glove and stocking hypothesia . Coordination was normal and plantar reflex was flexor bilaterally.