An 11-year-old boy presented with convulsion, fever, rash, abdominal pain, swelling on the eyelids, elbow and wrists, oliguria and hematuria. Based on the abnormal findings the patient was diagnosed with Henoch-Schönlein purpura. On the 3rd day of admission, neurological examination showed ataxic gait, loss of deep tendon reflexes, and decreased (4/5) of muscle strength on all extremities. Additionally, bilateral loss of touch, pain and temperature sensation in a glove, from the elbows to distal region (on C5-T1 level) was diagnosed. Cerebrospinal fluid examination and cranial magnetic resonance imaging (MRI) were normal. The patient was discharged with oral prednisolone on the 7th day of admission. One week after discharging from the hospital, he was re-admitted with vertigo and seizures. He was in coma. MRI of cranial, cervical and cervical plexus were normal. Electromyography showed severe bilateral brachial plexopathy. Prednisolone and intravenous immunglobulin (IVIG) therapy were given without significant improvement. He was discharged from the hospital on the 17th day of admission. On the second month of follow-up, a second cure of IVIG was given because of no clinical improvement. Now, he is on the 4th month of follow-up, unfortunately, no improvement was noted on his muscle strength and sensorial abnormalities on the upper extremities.