Primary and Secondary Red Ear Syndrome: Implications for Treatment

Approximately 57 patients with red ear syndrome have been reported in the literature since it was initially described in 1994. The clinical phenotype therefore continues to be defined and no consistent treatment response has been described. We report three new cases of red ear syndrome and suggest that the disorder may exist as a primary trigeminal or cervical autonomic cephalalgia, coexist with other rare trigeminal autonomic cephalalgias, or may be secondary. The pathogenesis in these different circumstances may be distinct, the triggers specific and, when secondary, the disorder may be more resistant to treatment.

Clinical and electrodiagnostic findings in copper deficiency myeloneuropathy

INTRODUCTION

Copper deficiency is an increasingly recognised cause of neurological impairment. This retrospective review highlights clinical and electrodiagnostic findings in patients diagnosed at our institution with copper deficiency.

METHODS

Clinical, radiographic and electrodiagnostic findings were reviewed in patients with evidence of copper deficiency. Patients with other potential causes of myelopathy or neuropathy were excluded.

RESULTS

The predominant clinical feature in all six patients was a sensory ataxia, resulting in marked gait unsteadiness. Nerve conduction studies and needle EMG were performed in all patients and revealed a mild to moderate distal, axonal, sensorimotor peripheral neuropathy. Median and tibial somatosensory evoked potentials were abnormal in all five patients in which it was performed, showing impaired conduction in central or proximal peripheral somatosensory pathways.

CONCLUSIONS

This pattern of electrodiagnostic findings suggests that impairment in somatosensory pathways demonstrated by somatosensory evoked potential testing is the main cause of the sensory ataxia in patients with copper deficiency.

Localization of a rapid CSF leak with digital subtraction myelography

A 53-year-old woman with superficial siderosis underwent spinal MR imaging, which demonstrated a large cervicothoracic epidural fluid collection compatible with a CSF leak. Conventional and dynamic CT myelography failed to localize the dural tear because of rapid equilibration of myelographic contrast between the thecal sac and the extradural collection. The superior temporal resolution of digital subtraction myelography precisely localized the CSF leak preoperatively and led to the successful surgical correction of the dural tear.

Probable adult polyglucosan body disease

Adult polyglucosan body disease is a clinicopathologic entity characterized by progressive upper and lower motor neuron dysfunction, sensory loss in the lower extremities, sphincter dysfunction, and occasionally dementia. Pathologically, numerous large polyglucosan bodies are noted in peripheral nerves, cerebral hemispheres, and the spinal cord, as well as in other systemic tissues. We present a case of probable adult polyglucosan body disease based on clinical history and examination, magnetic resonance images, and sural nerve biopsy findings.

Symptoms of 100 patients with electromyographically verified carpal tunnel syndrome

To determine the symptoms of carpal tunnel syndrome (CTS), screening evaluations were performed in 244 consecutive patients with sensory symptoms in the hand and unequivocal slowing of median nerve conduction at the wrist. This yielded 100 patients thought to have no explanation other than CTS for their upper limb complaints. These patients completed a hand symptom diagram (HSD) and questionnaire (HSQ) about their symptoms. CTS symptoms were most commonly reported in median and ulnar digits, followed by median digits only and a glove distribution. Unusual sensory patterns were reported by some patients. Based on the HSQ, paresthesias or pain proximal to the wrist occurred in 36.5% of hands. The usefulness of the HSD and HSQ for diagnosis was determined by asking three physicians, blinded to the diagnosis, to rate the likelihood of CTS in the patients with CTS and in 50 patients with other causes of upper extremity paresthesia. The sensitivities of the instruments ranged from 54.1% to 85.5%. Combining the HSD and HSQ ratings increased the range of sensitivities to 79.3% to 93.7%.

Peripheral neuropathy caused by proteolipid protein gene mutations

Pelizaeus-Merzbacher disease (PMD) is a dysmyelinating disorder of the central nervous system typically caused by duplications or missense mutations of the proteolipid protein (PLP) gene. Most investigators have found that peripheral nerve function and structure is normal in PMD patients. We have found that null mutations of the PLP gene cause demyelinating peripheral neuropathy, whereas duplications and a proline 14 to leucine mutation do not affect nerve function. A family with a nonsense mutation at position 144, which affects only PLP but not the alternatively spliced gene product DM20, has a very mild syndrome, including normal peripheral nerve function. Our findings suggest that DM20 alone is sufficient to maintain normal nerve function and that there may be domains of PLP/DM20 that have a relatively more active role in the peripheral nervous system compared with that in the central nervous system.

Proteolipid protein is necessary in peripheral as well as central myelin

Alternative products of the proteolipid protein gene (PLP), proteolipid protein (PLP) and DM20, are major components of compact myelin in the central nervous system, but quantitatively minor constituents of Schwann cells. A family with a null allele of PLP has a less severe CNS phenotype than those with other types of PLP mutations. Moreover, individuals with PLP null mutations have a demyelinating peripheral neuropathy, not seen with other PLP mutations of humans or animals. Direct analysis of normal peripheral nerve demonstrates that PLP is localized to compact myelin. This and the clinical and pathologic observations of the PLP null phenotype indicate that PLP/DM20 is necessary for proper myelin function both in the central and peripheral nervous systems.

Immune brachial plexus neuropathy: suggestive evidence for an inflammatory-immune pathogenesis

We report brachial plexus biopsy findings from two Australian and two American patients with brachial plexus neuropathy. There were florid multifocal mononuclear inflammatory cell infiltrates. Present evidence suggests that these brachial neuropathies have an immune basis.

Duchenne muscular dystrophy: deficiency of dystrophin-associated proteins in the sarcolemma

Dystrophin, the protein product of the Duchenne muscular dystrophy (DMD) gene, is a major component of the subsarcolemmal cytoskeleton and exists in a large oligomeric complex tightly associated with several sarcolemmal glycoproteins which provide a linkage to the extracellular matrix protein, laminin. In the present study, we investigated the status of the dystrophin-associated proteins in the skeletal muscle from 17 DMD patients of various ages. The results revealed a dramatic reduction in all of the dystrophin-associated proteins in the sarcolemma of DMD muscle compared with normal muscle and muscle from a variety of other neuromuscular diseases. This abnormality was common in all 17 DMD patients, irrespective of age. Our results indicate that the absence of dystrophin leads to the loss in all of the dystrophin-associated proteins, which renders DMD muscle fibers susceptible to necrosis. The analysis of dystrophin-associated proteins is important in the assessment of experimental therapies that attempt to replace dystrophin in DMD muscle.

Peripheral neuropathies associated with monoclonal proteins

Peripheral neuropathies associated with monoclonal proteins have received considerable attention as a clinically important group of chronic late-onset neuropathies. When a monoclonal protein is found in patients with peripheral neuropathy of unknown cause, as occurs in 10% of such cases, usually no associated disease is discovered; hence MGUS. Less often, disorders such as multiple myeloma, AL amyloidosis, Waldenström's macroglobulinemia, osteosclerotic myeloma, and lymphoma are found. Demyelinating neuropathies associated with MGUS of all classes, but particularly IgM, Waldenström's macroglobulinemia, and osteosclerotic myeloma typically follow an indolently progressive course, and frequently respond to treatments aimed at interfering with putative underlying immune mechanisms. By contrast, axonal neuropathies associated with MGUS, multiple myeloma, and AL amyloidosis have generally shown no response to therapy. Recently, IgM monoclonal and polyclonal antibodies directed against human peripheral nerve antigens including MAG and various glycolipids such as GM1 ganglioside have been found in patients with specific neuropathy syndromes. Anti-MAG antibodies occur in predominantly sensory demyelinating neuropathies, whereas elevated titers of anti-GM1 ganglioside antibodies are associated with lower motor neuron syndromes with multifocal motor conduction block. Although the evidence for autoimmune mechanisms in some monoclonal protein-associated neuropathies is mounting, a causal connection between monoclonal proteins and these neurologic syndromes has yet to be established.

Linkage localization of facioscapulohumeral muscular dystrophy (FSHD) in 4q35

Fasioscapulohumeral muscular dystrophy (FSHD) has recently been localized to 4q35. We have studied four families with FSHD. Linkage to the 4q35 probes D4S163, D4S139, and D4S171 was confirmed. We found no recombinants helpful in detailed localization of the FSHD gene. Two of our families include males with a rapidly progressive muscle disease that had been diagnosed, on the basis of clinical features, as Duchenne muscular dystrophy. One of these males is available for linkage study and shares the haplotype of his FSHD-affected aunt and cousin.

Class II antigen expression in peripheral neuropathies

The expression of class II antigen was studied in sural nerve biopsies from patients with peripheral neuropathies. These included patients with chronic demyelinating polyradiculoneuropathy (CIDP), non-immune mediated neuropathies of diverse etiologies and controls without evidence of neuropathy. The major finding in CIDP was a marked increase in class II expression on Schwann cells. Endoneurial Schwann cell staining to the same degree as in CIDP was seen in diabetic symmetric proximal motor neuropathy, neuropathies associated with monoclonal gammopathies and hereditary sensory and autonomic neuropathy type 1. In the control nerves and the other non-immune mediated neuropathies class II expression was mainly restricted to endothelial and perineurial cells. Increased endoneurial expression of class II antigen was found to correlate with elevated cerebrospinal fluid (CSF) protein levels but not with other clinical variables or demyelination as defined by electrophysiologic criteria or teased fiber analysis. The increased expression of class II antigen on Schwann cells may be indicative of a breakdown in immunological tolerance but should not be used as a diagnostic marker for dysimmune neuropathies due to overlap with non-immune mediated neuropathies.

Utilization of dietary precursors for carnitine synthesis in human adults

Endogenous synthetic pathways are presumed to be sufficient to provide adequate amounts of carnitine to meet the needs of the body. However, circulating carnitine levels of strict vegetarian adults and children, and particularly of infants fed carnitine-free formulas, are significantly lower than normal. Therefore, we investigated loci at which rates of carnitine synthesis may be restricted in human adults. Excess amounts of the carnitine precursors lysine plus methionine, epsilon-N-trimethyllysine or gamma-butyrobetaine were fed as supplements to a low carnitine diet for 10 d. Rate of carnitine synthesis was estimated by changes in carnitine excretion and changes in serum and muscle carnitine levels. Dietary gamma-butyrobetaine dramatically increased carnitine production, epsilon-N-trimethyllysine had a somewhat smaller effect, and lysine plus methionine had even less effect on carnitine synthesis. We conclude that carnitine synthesis is not limited by the activity of gamma-butyrobetaine hydroxylase. Carnitine synthesis from exogenous epsilon-N-trimethyllysine is limited either by enzymatic processes that lead to the final intermediate, gamma-butyrobetaine, or by the ability of this substrate to enter tissues capable of carrying out these transformations.

Axonal signals regulate expression of glia maturation factor-beta in Schwann cells: an immunohistochemical study of injured sciatic nerves and cultured Schwann cells

Glia maturation factor-beta (GMF-beta) is a 17 kDa protein purified and sequenced from bovine brains. Using the monoclonal antibody G2-09 directed against GMF-beta, we previously demonstrated endogenous GMF-beta in astroblasts, Schwann cells, and their tumors in culture. In the present study, we have used indirect immunofluorescence microscopy with G2-09 to examine the effects of transection, crush, and regeneration of sciatic nerve on the expression of GMF-beta in Schwann cells in situ and to study the time course of GMF-beta induction in Schwann cells in vitro. For comparison, a parallel study was carried out with monoclonal antibodies directed against nerve growth factor (NGF) receptor. We found that (1) neither GMF-beta nor NGF receptor was detectable in intact sciatic nerves, (2) all Schwann cells of the distal segment of the transected nerve expressed GMF-beta as early as 3 d after axotomy that persisted up to 3 weeks, (3) axonal regeneration repressed the Schwann cell expression of GMF-beta, (4) isolated Schwann cells derived from rat sciatic and adult human sural nerves developed intracellular GMF-beta in culture following an initial lag period, and (5) the induction of Schwann cell NGF receptor coincided temporally with that of GMF-beta in the transected nerve and in culture. These results show that the expression of GMF-beta in Schwann cells, as is the case with the NGF receptor, is induced by the loss of the normal axon-Schwann cell contact. We propose that the induction of GMF-beta, as well as NGF receptor, in Schwann cells after nerve injury plays a role in axonal regeneration.

Endogenous immunoreactive glia maturation factor-like molecule in cultured rat Schwann cells

Using the monoclonal antibody G2-09 raised against bovine glia maturation factor (GMF), we demonstrated that cultured rat Schwann cells and Schwannoma cells, but not their conditioned media, possessed endogenous GMF-like immunoreactivity. The presence of immunoreactive GMF correlated well with GMF bioactivity. The GMF-like factor in Schwann cells was characterized by immunodotting, immunofluorescence, immunoadsorption and immunoblotting. Immunofluorescence confirmed the intracellular location of GMF. Immunoadsorption completely eliminated the GMF-like bioactivity from the cell extracts. Immunoblotting identified a protein band with a molecular weight of 14,000. Thus, the evidence strongly supports the argument that the GMF-like factor in rat Schwann cells is identical with GMF from the bovine brain. The GMF-like molecule in Schwannoma cells showed properties similar to those in Schwann cells, but for unknown reasons was not detectable by immunofluorescence. The presence of GMF in cultured rat Schwann cells suggests that the factor may play a role in the peripheral nervous system.

Schwann cell-conditioned medium supports neurite outgrowth and survival of spinal cord neurons in culture

The effect of Schwann cell-conditioned medium (SCM) on the development in vitro of spinal cord neurons was studied. Spinal cord neurons from 18-day-old rat embryos were cultured in serum-free conditioned medium obtained from confluent rat Schwann cells. In cultures fed SCM, the cells developed typical neuronal morphology and were identified by indirect immunofluorescence using a monoclonal antibody to neurofilament protein. SCM stimulated neurite outgrowth and supported survival of spinal cord neurons. Preliminary characterization suggests that the neurotrophic factor in SCM appears to be a protein with a molecular weight greater than 8000 daltons.

Prediction of early beneficial response to plasma exchange in Guillain-Barré syndrome

We attempted to identify predictive factors of early beneficial response to plasmapheresis in Guillain-Barré syndrome (GBS). We reviewed 24 patients with typical severe GBS who underwent plasmapheresis and analyzed their outcome at one month. One group of 14 patients, designated as responders, improved dramatically, while ten patients showed little response. Age was the only important clinical predictor, with responders being younger. No other clinical variable (sex, preceding illness, severity, timing of plasmapheresis, cranial nerve involvement, or cerebrospinal fluid findings) reached significance. Among electrophysiologic parameters obtained before plasmapheresis, the amplitudes of compound muscle action potentials with distal stimulation of median and peroneal nerves were significantly reduced in non-responders. Plasmapheresis may improve only a subgroup of patients with GBS. Among patient characteristics, age and amplitudes of compound muscle action potentials are important predictors of early responsiveness.

Response to immunosuppressive therapy in patients with hereditary motor and sensory neuropathy and associated dysimmune neuromuscular disorders

We encountered 2 patients with hereditary motor and sensory neuropathy (HMSN) type I who had marked weakness developing during several months superimposed on chronic peroneal muscular atrophy. Further studies disclosed a chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in one patient and CIDP associated with polymyositis in the other. Both patients responded to prednisone and azathioprine with substantial improvement. Patients with HMSN who develop rapid progression of weakness should be evaluated for superimposed, potentially treatable dysimmune neuromuscular disorders.

Developmental Foix-Chavany-Marie syndrome in identical twins

Foix, Chavany, and Marie described a syndrome of faciopharyngoglossomasticatory diplegia resulting from bilateral anterior opercular infarction. We describe identical twins who have a developmental form of the syndrome. The twins, aged 41 years, were the product of a normal pregnancy and birth, but had subsequent delayed motor milestones, seizures, poor language development, mild mental retardation, drooling, absent gag reflexes, inability to protrude the tongue, brisk jaw jerks, impaired fine finger movements, symmetrical brisk reflexes, flexor plantar responses, and mildly spastic gait. Magnetic resonance imaging showed bilateral perisylvian cortical dysplasia compatible with polymicrogyria and incomplete opercular formation.

Movement disorders associated with chronic GM2 gangliosidosis. Case report and review of the literature

A 24-year-old man presented with dystonia, dementia, amyotrophy, choreoathetosis, and ataxia. Partial hexosaminidase A deficiency was documented in serum and leukocytes and confirmed by rectal biopsy with ganglion cells containing membranous cytoplasmic bodies. A brief review of the literature reveals that tremor, dystonia and choreoathetosis are common but neglected symptoms associated with chronic GM2 gangliosidosis.

Somatosensory evoked potentials in motor neuron disease

We studied median somatosensory evoked potentials (SEPs) in an unselected series of 30 patients with sporadic motor neuron disease (MND). SEPs were affected in 17 patients (57%), with a higher incidence of abnormality in amyotrophic lateral sclerosis and bulbar palsy than in progressive muscular atrophy. In a majority of patients, simultaneous bilateral stimulation of the median nerve revealed a delay or absence of scalp-recorded central N32 and/or N60, leaving the earlier peaks intact. In the remaining cases, the N19 peak was asymmetrically prolonged. These findings suggest common involvement of somatosensory pathways in MND, either at cortical or subcortical levels, and correlate with neuropathologic reports of neuronal degeneration beyond the primary motor system.

Chronic long-interval plasma exchange in myasthenia gravis

Plasma exchange, when used in conjunction with azathioprine to treat chronic symptoms of myasthenia gravis, can usually be discontinued after a limited period of time without reappearance of symptoms. Patients who cannot be weaned from the procedure are often treated with more potent immunosuppressants to overcome exchange dependence. In view of the cumulative risks of more intensive daily immunosuppression, continuation of intermittent plasma exchange can be an acceptable alternative provided the interexchange interval (IEI) is relatively long. We describe two exchange-dependent patients in whom plasma exchange has been used for 4 1/2 and five years to control their symptoms. In both patients, who also received azathioprine, the IEI gradually lengthened to nine or 12 weeks over two to three years, without the introduction of new immunosuppressants. These cases illustrate that long-term plasma exchange is feasible and effective in selected exchange-dependent patients with myasthenia gravis.

Glia maturation factor promotes proliferation and morphologic expression of rat Schwann cells

Glia maturation factor (GMF) is an acidic protein with a molecular weight of about 20,000 daltons, found in the adult brain of many species. Previously GMF was observed to stimulate the proliferation and subsequent maturation of rat astroblasts in culture. We investigated the effects of GMF on Schwann cells. Schwann cells were dissociated from rat sciatic nerve and purified by means of antimitotic agents and by selective immunoadsorption of contaminating fibroblasts. Cultured Schwann cells after 3 passages assumed a flat polygonal shape. Exposure of the cells to GMF converted the cells to the elongated, spindle morphology typical of Schwann cells. GMF also stimulated a 7-fold increase in DNA synthesis when compared with control cultures grown in F10 medium containing 5% fetal calf serum. The mitogenic activity of GMF was still detectable at 5 ng protein/ml medium. The maximal effect on DNA synthesis occurred 72 h after the initial exposure to GMF. Although the cells were positive for the Schwann cell marker Ran-1, GMF failed to induce the production of myelin-associated glycolipids (galactocerebroside) and proteins (Po) nor did it induce the astrocytic marker glial fibrillary acidic protein (GFAP). The effects of GMF on Schwann cells extend its biological role beyond the central nervous system.

Purification of rat Schwann cells from cultures of peripheral nerve: an immunoselective method using surfaces coated with anti-immunoglobulin antibodies

We report a method for deriving purified rat Schwann cells by immunoselective removal of fibroblasts. Contaminating fibroblasts labeled with antibody against specific surface marker Thy 1.1 are bound on plastic surfaces coated with a second antibody. The efficacy of the method is demonstrated by flow cytometry and by specific Schwann cell Ran-1 immunofluorescence.

First report of mosaic trisomy 12 in a liveborn individual

Trisomy 12 mosaicism was found in a 36-year-old woman with minor anomalies, neuromuscular abnormalities, and moderate mental retardation. Trisomy 12 was present in 13% of the lymphocytes but not in skin fibroblasts. Previous reports of dup (12p) and dup(12q) are reviewed. To our knowledge this is the first report of a "complete" trisomy 12 in a liveborn individual.

Peripheral neuropathy associated with monoclonal gammopathy. Studies of intraneural injections of monoclonal immunoglobulin sera

A causal relationship between paraproteinemia and neuropathies has been suggested. We studied three patients with chronic sensorimotor polyneuropathy associated with plasma cell dyscrasia and monoclonal gammopathies (IgGK, IgMK, IgA lambda). Sural nerve biopsies showed mild (2 cases) to moderate loss of myelinated fibers (1 case). Teased single fiber studies showed segmental demyelination-remyelination in two patients. Direct immunofluorescence demonstrated immune deposits of the myelin sheath of the same specificity as the serum paraprotein, IgGK (1 of 3 cases). Treatment with prednisone, melphalan or chlorambucil, and plasmapheresis resulted in remission (1 case), partial improvement (1 case), or had no effect (1 case), although reduction of monoclonal immunoglobulin occurred in all. To investigate the role the paraproteins might play in the pathogenesis of the neuropathy, patients' serum was injected intraneurally into rat sciatic nerves. None of the animals developed weakness, slowing of in vitro conduction of sciatic nerve, or significant evidence of demyelination by light- or electron-microscopy or teased single fiber studies 48 hours postinjection. Similar injections of rabbit serum with experimental allergic neuritis (EAN) produced focal segmental demyelination. Our studies employing an in vivo bioassay technique failed to establish antimyelin activity of monoclonal immunoglobulin sera.

Disulfiram neuropathy: a neurofilamentous distal axonopathy

Disulfiram is used to treat alcoholism and is known to cause peripheral neuropathy: few reports of biopsied human nerves have revealed axonal degeneration and loss of myelinated fibers. We studied a 22-year-old woman with severe sensorimotor neuropathy following treatment with disulfiram for 6 months. Histologic studies of the sural nerve revealed a neurofilamentous axonopathy with rare enlarged axons distended by neurofilaments. Disulfiram is converted enzymatically to carbon disulfide, which causes neurofilamentous distal axonopathy in animals. Similar changes in human nerve after disulfiram administration suggest that carbon disulfide is the toxic agent.

Peripheral neurofibromatosis and peroneal muscular atrophy

We studied four patients with peripheral neurofibromatosis and a neuropathy that had the clinical characteristics of peroneal muscular atrophy. Nerve conduction velocities were slowed by less than 40% of normal, and electromyography demonstrated denervation. Sural nerve biopsies from two patients, which were macroscopically free of nerve sheath tumors, were studied by recording the compound action potentials in vitro and by morphometry. These studies demonstrated a chronic axonal neuropathy with reactive Schwann cell changes. Peroneal muscular atrophy in association with neurofibromatosis may be due to progressive neuronal degeneration and may represent another, uncommon manifestation of peripheral neurofibromatosis.

Peripheral Nerve unmyelinated axons following lumbar sympathectomy

One year after bilateral lumbar sympathectomy for Raynaud's syndrome, a young woman underwent fascicular biopsy of the sural nerve to help elucidate the cause of lower limb pain. The morphological features, density, and diameter spectrum of unmyelinated fibers were normal. The sympathetic nervous system appears to contribute few, if any, axons to the total population of unmyelinated axons in this cutaneous nerve.

Chronic tetanus: clinical report and histochemistry of muscle

A patient who was partially immune to tetanus developed nonfulminant tetanus after a minor injury. Manifestations of the disease persisted for over 17 months. Electrophysiologic studies revealed an absent silent period in the masseter muscle, large-amplitude F-responses, and denervation. A muscle biopsy showed neurogenic atrophy with reinnervation. This observation supports the existence of chronic tetanus and provides morphologic evidence for a peripheral action of tetanus toxin in humans.

Brachial plexus involvement in familial pressure-sensitive neuropathy: electrophysiological and morphological findings

Two family members with hereditary pressure-sensitive neuropathy are reported. One patient presented atypically with acute brachial plexus neuropathy following transaxillary removal of the first rib. Electrophysiological studies showed slowing of motor nerve conduction in clinically affected and unaffected nerves. In vitro recording of the compound action potential of the subclinically involved sural nerve showed pronounced slowing in conduction of large and small myelinated fiber groups. These alterations correlated with morphological studies of the sural nerve that showed tomacula with acute and healed segmental demyelination. An inherited, generalized neuropathy manifested by a morphological abnormality of myelination may render peripheral nerves unduly susceptible to mechanical trauma, including positional pressure or traction effects during general anesthesia.

Animal models of alcoholic neuropathy: morphologic, electrophysiologic, and biochemical findings

A chronic high alcohol intake was induced in rats through the use of two procedures: the schedule-induced polydipsia technique and the liquid diet technique. Rats consumed 11-12 g of ethanol per kilogram body weight per day for 16 to 18 weeks. Morphologic evidence of a mild distal axonal neuropathy in the ventral caudal nerve was proposed. The red blood cell transketolase levels were normal, indicating that the rats were not deficient in thiamine and suggesting that the axonal degeneration was due to the direct toxic effect of alcohol. Axonal transport studies demonstrated a significant increase in the amount of acetylcholinesterase transported in an orthograde direction in the sciatic nerves of alcohol-exposed rats, and indicated no change in the transport of choline acetyltransferase or in the specific binding of colchicine by neurotubulin.

Inflammatory myopathy in oculopharyngeal dystrophy

A 75-year-old French-Canadian woman with familial oculopharyngeal dystrophy demonstrated histopathologic alterations similar to those of idiopathic polymyositis. A second biopsy obtained 15 months later was more consistent with previously reported cases. It is suggested that certain patients with oculopharyngeal dystrophy may pass through an initial phase of secondary muscle inflammation similar to that seen in some other heritable myopathies.

Late adult-onset metachromatic leukodystrophy. Dementia and polyneuropathy in a 63-year-old man

A diagnosis of adult-onset metachromatic leukodystrophy (MLD) was established in a living 63-year-old man with progressive dementia and peripheral neuropathy. Decreased nerve conduction velocities and elevated spinal fluid protein concentration led to more specific diagnostic studies required to confirm the diagnosis. This case expands the spectrum of adult-onset MLD to patients with dementia and polyneuropathy past the sixth decade of life. Measurement of nerve conduction velocities may help to uncover cases of adult-onset MLD and should be included in the evaluation of dementia.

Myasthenia gravis and Schmidt syndrome

A patient with myasthenia gravis developed both Addison disease and primary hypothyroidism, with demonstrable anti-adrenal and antithyroid antibodies in her serum. The association of myasthenia gravis with Schmidt syndrome does not seem to be a chance occurrence, considering the autoimmune pathogenesis of each of these disorders.

Effect of hematin in porphyric neuropathy

Early, intravenous administration of hematin in a patient with acute intermittent porphyria and severe quadriparesis may have produced partial but remarkable improvement of neuropathy, and resulted in simultaneous decline of porphyrin precursors in the blood. Intermittent, biweekly hematin infusions given 1 month after the onset of the porphyric relapse had no effect on recovery of the residual neuropathy. We believe hematin may be effective in the treatment of porphyric neuropathy, if administered before irreversible neuronal damage has occured.

Neurologic aspects of hereditary hemorrhagic telangiectasia. Report of two cases

The several neurologic manifestations of hereditary hemorrhagic telangiectasia (HHT) may be caused by complications of pulmonary arteriovenous fistulae or associated central nervous system vascular malformations. The presence of skin and mucosal telangiectases should alert the clinician to the possibility of the disorder and in turn of its potential for associated neurologic disease, including cerebral hemorrhage and abscess. This report describes two cases and demonstrates that the clinical spectrum of HHT should be enlarged to include its admittedly rare, but serious, neurologic aspects.

Ocular bobbing: the myth of its localizing value

Ocular bobbing is a distinctive eye movement disorder seen in patients with pontine dysfunction. The typical phenomenon consists of abrupt, spontaneous downward jerks of the eyes with a slow return to the midposition in association with paralysis of spontaneous and reflex horizontal eye movements. Bobbing was present in a patient with acute cerebellar hemorrhage in whom no intrapontine lesions could be demonstrated. The myth that this sign is specific for intrapontine destruction has to be abandoned.