42 years male pt was admitted to hospital with quadriplegia .his condition started as a weakness in both lower limbs and gradually within 2 weaks became quadriplegic. No history of fever or any source of infection before the attack. By examination : Hypotonia with absent reflexes and intact sensations in both lower and upper limbs . Bilateral LMN facial paralysis and bulbar palsy. Radiology: CT brain is normal Spinal MRI is normal .