Guillain Barré Syndrome in a multiple myeloma patient after the first course of bortezomib therapy: A case report.

Bortezomib is approved for treating relapsed multiple myeloma (MM) and mantle cell lymphoma, and clinical evidence has shown complete clinical responses in MM patients. Peripheral neuropathy is one of the most common adverse effects of bortezomib. However, rare evidence has shown that bortezomib is associated with Guillain-Barré syndrome (GBS). In the present study, a case of GBS is reported in an MM patient finishing the first course of bortezomib therapy. Based on a bone marrow cell examination revealing 34% plasma cell infiltration and according to the International Staging System, the patient was diagnosed with stage III MM (λ type). Thus, a chemotherapy protocol was performed, which consisted of bortezomib and dexamethasone. However, 5 days after the first cycle, paresthesias of the upper and lower limbs developed. Standard nerve conduction studies revealed marked reduction of the motor conduction velocity of the median nerve bilaterally and of the right ulnar nerve, while sensory conduction was significantly slowed in the majority of the nerves of the upper and lower limbs. However, there was no evidence of demyelination. With this clinical evidence, a diagnosis of GBS was considered. The patient was subsequently treated with high-dose intravenous immunoglobulins (IVIGs; 400 mg/kg/day for 5 days). Following IVIG treatment, the symptoms were largely relieved. This study suggested that GBS may occur when administering bortezomib, and that high-dose IVIGs could treat the symptoms of GBS.