Neurology
-
We characterized postural stability in patients with Huntington's disease (HD) by examining their ability to use different sensory cues to maintain balance and by recording their automatic postural responses to externally applied perturbations. Our HD patients, like normal subjects, depended more on proprioceptive than on visual cues to maintain balance. ⋯ The onset of compensatory motor responses in the lower extremities following sudden translations of the support surface was delayed by 30 to 60 msec in HD patients as compared with normal subjects. HD patients also had more sway and falls during unexpected rotations of the support surface, although they could appropriately reduce their motor responses on the next trial.
-
Comparative Study
Chronic inflammatory demyelinating polyradiculoneuropathy: comparison of patients with and without an associated monoclonal gammopathy.
We reviewed our data from patients with the clinical diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Seventy patients had no demonstrable underlying disease to account for their polyneuropathy and were classified as idiopathic CIDP (CIDP-I). We detected a monoclonal gammopathy of uncertain significance (MGUS) in 30 patients who were classified as CIDP-MGUS; 17 had an IgG gammopathy, 12 an IgM gammopathy, and one an IgA gammopathy. ⋯ There were no significant differences in motor and sensory nerve conduction measures between CIDP-I and CIDP-MGUS patients, nor between CIDP-MGUS patients with IgM and those with IgG or IgA gammopathy. Strict electrodiagnostic criteria for primary demyelination were fulfilled by 54% of CIDP-I patients and 40% of CIDP-MGUS patients, but these were not significantly different. Our study suggests that (1) the demographic features and immunoglobulin class distribution of CIDP-MGUS patients largely reflect those of patients with an MGUS, but without polyneuropathy, (2) CIDP-MGUS patients as a group cannot be distinguished from CIDP-I patients on the basis of nerve conduction studies, and (3) IgM CIDP-MGUS patients cannot be distinguished from those with other immunoglobulin classes.