Electrodiagnostic study of peripheral nervous system [PNS] in 30 patients with multiple myeloma

ABSTRACT

Involvement of the peripheral nervous system is one of the complications of multiple myeloma with a varying incidence of clinical and subclinical neuropathy in different studies. As most of the patients with multiple myeloma suffer from generalized systemic symptoms such as malaise, bone and low back pain, the clinical clues to the diagnosis of the neuropathy in its initial stages could be ignored. In this study, we tried to determine the frequency of peripheral nervous system involvement in these patients by electromyography/nerve conduction [EMG/NCV] studies. This cross-sectional descriptive study of 30 patients with multiple myeloma revealed that 70% of cases showed peripheral nervous system involvement, of whom 57% were found to be asymptomatic and 43% symptomatic for peripheral nervous system disease. The pattern of peripheral nervous system involvement was polyneuropathy [62%] followed by radiculopathy and carpal tunnel syndrome, 52% and 29%, respectively. Most of the neuropathies were of the sensorimotor axonal type. L5, S 1 roots were the most common sites of radiculopathies. Therefore we conclude that the frequency of subclinical peripheral nervous system involvement in multiple myeloma patients was so rampant that evaluation of multiple myeloma patients with EMG/NCV studies was necessary