P-PN003. Refractory chronic inflammatory demyelinating polyneuropathy treated with subcutaneous bortezumib

Abstract

Introduction. A 73-year-old man with underlying diabetes presented in May 2017 with progressive bilateral upper and lower limb weakness and numbness for 3 months. Examination revealed power of 2-3 on lower limbs and 3 on upper limbs. Reflexes were absent with gloves and stocking sensory loss. NCS showed diffused sensorimotor demyelinating polyneuropathy. Monoclonal IgG kappa was detected. Urine free light chain showed raised kappa. However, BMAT showed no evidence of myeloma. Abdominal fat pad biopsy showed no evidence of amyloidosis. Anti-ganglioside and paraneoplastic antibodies were not detected. Sural nerve biopsy showed axonal loss. CT NTAP was unremarkable. He responded initially with IVIG therapy but In July 2017, he had a relapse with worsening lower limb weakness. He was given IVIG 1 g/kg maintenance together with dexamethasone 4 weekly pulse therapy with some improvement. In Oct 2017, he presented again with worsening weakness. Besides, there was dysphagia and dysphonia. He developed type 2 respiratory failure requiring NIV and ICU admission, requiring 2 weekly plasmapheresis to rescue him from recurrent respiratory failure. IV Rituximab was tried but with little success even after 1 month of completion. Subcutaneous Bortezumib was given for 2 courses; Feb 2018 and Aug 2018. Results. After first course of Bortezumib, he improved significantly; with no more dysphagia and respiratory failure. He was subsequently discharged in Apr 2018, since then on monthly maintenance plasmapharesis and later 3 monthly. Upon latest review in Nov 2019, he was able to ambulate independently; muscle power improved with upper limbs proximal 5, distal 3; lower limbs proximal 5, distal 4. NCS showed improvement of motor CMAP especially in upper limbs. Conclusion. Bortezumib can be considered in refractory CIDP despite limited experience in the literature. However it should be reserved after conventional therapies have failed due to its neurotoxic side effects.