Chronic inflammatory demyelinating polyneuropathy (CIDP) is a disorder characterized by motor symptoms such as weakness in both proximal and distal muscles with globally diminished or absent reflexes. Insulin neuritis is referred as an acute pain in the extremities, due to the damage of peripheral nerves affecting mainly small fibers, in diabetic patients treated with insulin who achieved rapid glycemic control. Pain is unusual in classic CIDP. We report the case of a 54-year-old female patient with type II diabetes mellitus, and a recent onset of insulin therapy, who presented at the emergency room with a 2-month history of weakness and hyperalgesia of extremities. Physical examination showed marked pain and proximal and distal allodynia in the 4 limbs, with reduced muscle strength of the proximal muscles and patellar and achillear areflexia. Electrophysiological study showed sensory and motor polyneuropathy with a demyelinating predominance. Treatment with recombinant human immunoglobin was started, and the patient presented a total remission of the condition. Complementary studies confirmed weak serum positivity of GM1, GD1a, GD1b and anti-asialo GM1. Prior to hospital discharge, results of positive serum VDRL and FTA-Abs were received. VDRL in cerebrospinal fluid was negative, so neurosyphilis was ruled out, and treatment with benzathine penicillin was indicated.
Keywords: chronic inflammatory demyelinating polyneuropathy; diabetes.