Inclusion body myositis a clinical review with illustrative case report.

Every acute physician has come across elderly patients presenting with muscle weakness and falls. Distinction between normal age related muscle wasting and pathological muscle atrophy can be difficult. It is important for acute physicians to be aware of the differential diagnosis of such a presentation. Inclusion body myositis(IBM) is the most common type of acquired myopathy above the age of 50.1 This article aims to highlight the diagnosis and management of this chronic illness. It is frequently misdiagnosed as polymyositis and wrongly treated with steroids.3 The typical symptoms and signs are illustrated by a recent case which presented to our department (see box 1).

Extrapontine myelinolysis presenting as acute parkinsonism.

BACKGROUND: Extrapontine myelinolysis presenting with extra pyramidal features suggestive of parkinsonism may be a challenging clinical syndrome. Clinicians should maintain their vigilance while correcting electrolyte imbalances, especially with associated co-morbidity. CASE PRESENTATION: A 41-year-old woman presented with acute parkinsonism like features while on a holiday. This followed slow correction of hyponatraemia after repeated vomiting. MRI changes were suggestive of Extrapontine myelinolysis(EPM). This case is at variance with four previous cases reported in the medical literature in that the patient made a full clinical recovery and the MR changes resolved with symptomatic support alone. CONCLUSION: Extrapontine myelinolysis could make a complete recovery with symptomatic support alone. During hyponatraemia correction, rapid osmotic shifts of fluid that cause hypernatremia, causes myelinolysis rather than absolute serum sodium level. Even gradual correction of hyponatraemia can produce myelinolysis, especially with pre-existing malnourishment, alcoholism, drug misuse, Addison's disease and immuno-suppression. Pallidial sparing is typical of EPM in MRI scans.

The clinical and laboratory features of chronic sensory ataxic neuropathy with anti-disialosyl IgM antibodies.

The clinical and laboratory phenotype of a paraproteinaemic neuropathy syndrome termed chronic sensory ataxic neuropathy with anti-disialosyl IgM antibodies is described in a series of 18 cases. Previous single case reports have outlined some features of this syndrome. All 18 cases were defined by the presence of serum IgM antibodies which react principally with NeuAc (alpha2-8)NeuAc(alpha2-3)Gal-configured disialosyl epitopes common to many gangliosides including GDlb, GD3, GTlb and GQlb. In 17 out of 18 cases, the serum contained benign IgM paraproteins, and in four of these cases at least two IgM paraproteins were present. The IgM antibodies were also cold agglutinins in 50% of cases. The clinical picture comprised a chronic neuropathy with marked sensory ataxia and areflexia, and with relatively preserved motor function in the limbs. In addition, 16 out of 18 cases had motor weakness affecting oculomotor and bulbar muscles as fixed or as relapsing-remitting features. When present in their entirety, these clinical features have been described previously under the acronym CANOMAD: chronic ataxic neuropathy, ophthalmoplegia, IgM paraprotein, cold agglutinins and disialosyl antibodies. This distribution of clinical features is reminiscent of Miller Fisher syndrome, in which acute-phase anti-disialylated ganglioside IgG antibodies are found. Clinical electrophysiology and nerve biopsy show both demyelinating and axonal features. A partial response to intravenous immunoglobulin and other treatments is reported in some cases.

The effect of oral and intravenous methylprednisolone treatment on subsequent relapse rate in multiple sclerosis.

We investigated the effect of oral and intravenous methylprednisolone treatment on subsequent relapse rate in patients with multiple sclerosis. Following a double blind trial designed to compare the effect of oral and intravenous methylprednisolone treatment on promoting recovery from acute relapses of multiple sclerosis, 80 patients were followed for two years with six-monthly assessments during which all subsequent relapses were recorded. The annual relapse rate was slightly higher in the oral compared with the intravenous methylprednisolone-treated patients (1.06 vs. 0.78), but the adjusted difference between the two groups was not statistically significant (0.18; 95% CI -0.19 to 0.55, P=0.3). The time to onset and the severity of the first relapse after treatment, the number of relapse free patients at the end of the follow-up period, and the severity of the relapses during the follow-up period were similar in the two groups. This trial did not show a statistically significant difference in relapse rate during the first two years following oral compared with intravenous methylprednisolone treatment.

Evoked potentials in a subject with a large-fibre sensory neuropathy below the neck.

The results from experiments in various modalities of evoked potentials are described in a subject with a complete large peripheral neuropathy below the neck. He has no tactile or position sensitivity below that level, but has retained fatigue, pain, and temperature sensation. Percutaneous electrical stimulation of peripheral nerves led to scalp recorded evoked potentials with thresholds and propagation velocities compatible with conduction along A-delta peripheral pathways. CO2 laser evoked potentials were similar to those seen in controls, further support for intact A-delta peripheral fibres. Movement-related cortical potentials (MRCPs) were recorded associated with active and passive movement of the middle finger. The former were normal, evidence that the termination of the MRCP is not dependent on peripheral feedback. By comparing passive MRCPs between controls and the subject it was possible to establish which parts of the potentials are visual and which are proprioceptive and to gain evidence of central reorganisation in the subject. Magnetic brain stimulation was used to show that the subject did not perceive induced movement, had a normal centrally originating silent period, and could focus his attention during real and imagined movement of the finger more successfully than could normal controls.

Evoked potentials in a man with a complete large myelinated fibre sensory neuropathy below the neck.

Cortical somatosensory evoked potentials (SEPs) were recorded from a man with a severe neuropathy without touch and proprioception below the neck. Peripheral neurophysiological tests showed a complete large myelinated fibre sensory neuropathy. Sensory threshold to electrical stimulation of the median nerve was 15 mA (normal 2-4 mA). With a stimulus of 39 mA, duration 400 microsecons, applied at the wrist a cortical SEP was recorded with a latency of 84 msec, giving a propagation velocity of 11.9 m/sec. At stimulation rates of above 3.3 Hz the SEP was absent. It is concluded that the SEPs recorded were conducted along A delta peripheral fibres.

Evaluation of the dermatomal somatosensory evoked potential in the diagnosis of lumbo-sacral root compression.

The dermatomal somatosensory evoked potential from the lumbo-sacral dermatomes was recorded from 21 patients with radiographically and surgically (20) proven lumbo-sacral root compression due to prolapsed intervertebral disc or canal stenosis. The potential was abnormal in 19 of the 20 surgically proven cases. The dermatomal somatosensory evoked potential is as accurate as myelography for diagnosis but has the advantage of being non-invasive and repeatable. It provides useful additional diagnostic and pathophysiological information about lumbo-sacral root compression.

Somatosensory evoked potentials from posterior tibial nerve and lumbo-sacral dermatomes.

Techniques for recording the somatosensory evoked potential following stimulation of the skin of L5 and S1 dermatomes are described and validated. Normal data and their range are given for 54 subjects (108 legs). The latency of the peak of the first positive wave (P40) can be predicted from the subject's height from the regression formulae: P40 latency in msec = height in metres X 23.7 + 8.6 for the L5 dermatome. P40 latency in msec = height in metres X 24.5 + 8.7 for the S1 dermatome. P40 latency in msec = height in metres X 15.0 + 14.6 for the posterior tibial nerve. The standard deviations are 2.90 for L5; 2.95 for S1 and 1.60 for the posterior tibial nerve. Age and sex of the subjects had no significant effect. The data will have value when dermatomal somatosensory evoked potentials are used to investigate radiculopathies.