Associated central and peripheral demyelination: an electrophysiological study

Patterns and significance of concomitant central and peripheral inflammatory demyelination

Inflammatory demyelinating diseases comprise a spectrum of disorders that affect central nervous system (CNS) and peripheral nervous system (PNS) myelin. Most individuals have demyelinating disease restricted to one or the other compartment but patients with concomitant CNS and PNS inflammatory inflammatory demyelinating processes have been reported not infrequently. In most such patients, involvement of either the CNS or the PNS predominates the clinical picture. Involvement of the other compartment is usually mild or subclinical with unclear prognostic and therapeutic implications. Similarly, while experimentally induced demyelinating disease in animal models is usually CNS or PNS predominant, varying degrees of pathology in the other system can occur depending on the species, type of immunogen, and genetic background of the immunized animal. When CNS and PNS demyelinating diseases occur concurrently, effective treatment for CNS disease can be safely combined with effective treatment for PNS disease.

Chronic inflammatory demyelinating polyradiculoneuropathy associated with multiple sclerosis

OBJECTIVE

To describe temporal profile of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in patients with definite, relapsing multiple sclerosis (MS).

BACKGROUND

Peripheral demyelinating neuropathy has been rarely reported in association with central nervous system demyelinating disorder indistinguishable from MS.

METHODS

In addition to usual diagnostic studies for CIDP and MS in all 5 patients, we studied proximal segments of nerves using deep tendon reflex latency measurements of biceps reflex, patellar reflex, and ankle reflex.

RESULTS

All patients with MS subsequently (4-22 years) developed definite CIDP. Two of these patients developed multiple cranial nerve and spinal root enhancement on subsequent imaging without new intraparenchymal enhancement after a diagnosis of CIDP. The deep tendon reflex latencies were prolonged at more than 2 sites in all patients. Cerebral spinal fluid protein increased (70 +/- 19 to 144.8 +/- 17.4 mg/dL, P = 0.0001) at time of diagnosis of CIDP. Clinical improvement was observed in all patients after intravenous immunoglobulin therapy.

CONCLUSIONS

When patients with MS develop CIDP, manifestations of central and peripheral disease involvement seem to respond to intravenous immunoglobulin. These cases suggest that there may be common antigenic targets in central and peripheral nervous system in this subset of patients.

Steroid-responsive multifocal demyelinating neuropathy with central involvement

We describe 2 patients with associated central and peripheral demyelination. Electrophysiological studies revealed a demyelinating polyneuropathy with sensory and motor conduction blocks. Visual evoked potentials were abnormal. Motor evoked potentials showed abnormal central conduction time in 1 patient. Magnetic resonance imaging revealed regions of abnormal high signal in the spinal cord and brain; sural nerve biopsy disclosed a demyelinating neuropathy. Both patients showed clinical and electrophysiological improvement after steroid therapy.

Central nervous system involvement in multifocal demyelinating neuropathy with persistent conduction block

We report the case of a 27-year-old man treated for bilateral optic neuritis 5 and 3 years before who within a few months developed sensorimotor disorders of the arms and legs characterized by asymmetric distribution and distal prominence. In addition to sensorimotor defects, which were particularly marked in the left arm and right leg, clinical examination showed nearly generalized areflexia. Electrophysiological studies revealed a multifocal neuropathy with persistent distal and proximal conduction blocks associated with a considerable slowing of motor nerve conduction, as well as central nervous system involvement indicated by motor-, somatosensory-, and visual-evoked potentials. CSF analysis showed a mildly elevated protein level; anti-GM1 activity was negative. Sural nerve biopsy revealed onion-bulb-like formations, and cerebral MRI showed a small, isolated, and aspecific high signal for white matter. First described by Lewis and Sumner in 1982, multifocal neuropathy with persistent conduction blocks may be associated with central demyelination. Our case is compared with 3 similar ones in the literature, and the favorable effects of steroid therapy are emphasized.

Chronic multifocal demyelinating neuropathy associated with central nervous system demyelination

We have carried out a long-term study of lesions found in a man who had a demyelinating disease of both central and peripheral nervous systems. During the 10 years of his clinical course, he suffered from optic neuritis, multifocal myelitis, and chronic multifocal demyelinating neuropathy, with persistent conduction block. Our study revealed that both central and peripheral nervous system demyelination occurred repeatedly and simultaneously.

[Late recurrence of Miller-Fischer syndrome. Physiopathogenic reflections about a case]

The physiopathology of the syndrome of ophtalmoplegia-ataxia-areflexia-hyperproteinorachia, firstly described by FISHER in 1956, remains a matter of controversy among neurologists. We report a new case of recurrence of a MILLER-FISHER's syndrome. The involvement of peripheral and central structures is discussed according to recent knowledges about the immunopathology of inflammatory polyneuropathies.