Paraneoplastic pure motor neuropathy in a 48-year-old male with recently diagnosed DLBCL
Avinash Kolli1, Anooshah Ata1, Rebecca Hurst1
1Neurology, USF-Morsani College of Medicine
Objective:
To report a case of paraneoplastic pure motor neuropathy associated with DLBCL
Background:
Paraneoplastic lower motor neuron disease is a rare clinical entity. Patient’s present with a slow progressive painless asymmetric weakness in the limbs and without upper motor neuron features. Neoplasms that are associated with this syndrome include: lymphoma, ovarian, breast, renal, and lung cancers. Usually, no paraneoplastic antibodies are identified. We report a case of a 48-year-old male with newly diagnosed DLBCL, a non-Hodgkin lymphoma (NHL), who presented with subacute painless asymmetric upper extremity weakness without clear sensory loss prior to initiation of any chemo or radiation therapy. Imaging of the bilateral plexus and cervical spine did not reveal enhancement or infiltration and cerebrospinal fluid studies were unrevealing. Electromyography provided evidence of a primarily demyelinating greater than axonal purely motor polyradiculoneuropathy limited to the arms. Neurological improvement was seen with intravenous immunoglobulin and treatment of malignancy.
Conclusions:
Upon literature review, a case of paraneoplastic purely motor neuron syndrome associated with an NHL such as DLBCL has not been described before. There have been reports of paraneoplastic neurological syndromes associated with NHL none of which were purely motor neuron disease. Flanagan et al reported a similar case of paraneoplastic motor neuron disease associated with a type of Hodgkin’s Lymphoma. Similarly, to their findings, we observed neurological improvement with concurrent IVIG and treatment of the underlying malignancy. This case highlights the continued role for documentation of peripheral neuropathies secondary paraneoplastic etiologies with goals to further characterize novel onconeural antibodies.