Autonomic dysfunction in polyneuropathies: a report on 106 cases

Prevention and management of adverse events of novel agents in multiple myeloma: a consensus of the European Myeloma Network

During the last few years, several new drugs have been introduced for treatment of patients with multiple myeloma, which have significantly improved the treatment outcome. All of these novel substances differ at least in part in their mode of action from similar drugs of the same drug class, or are representatives of new drug classes, and as such present with very specific side effect profiles. In this review, we summarize these adverse events, provide information on their prevention, and give practical guidance for monitoring of patients and for management of adverse events.

Autonomic dysfunction in Guillain-Barré syndrome and multiple sclerosis

This review gives an overview of autonomic dysfunction encountered in Guillain-Barré syndrome (GBS) and multiple sclerosis (MS). In GBS, cardiovascular dysregulation is common and may lead to serious bradyarrhythmias that need to be recognised for the early initiation of appropriate therapy. Although standardised autonomic tests were useful for the diagnosis of autonomic failure, they were not able to indicate vagal over-reactivity. In this regard, eyeball pressure testing may correctly identify patients at risk for impending and potentially life-threatening bradyarrhythmias which may easily be administered at the bedside. In MS, cardiovascular autonomic dysfunction is usually of minor clinical importance. However, orthostatic intolerance may be present in approximately 50% of patients and could easily be detected by routine measurements of heart rate and blood pressure during rest and during standing. More subtle alterations may require more sophisticated methods such as autonomic reflex testing or baroreflex stimulation. Several in vitro, animal and clinical studies provide evidence that there are many interactions between the sympathetic nervous system and the immune system giving rise to the hypothesis that autonomic dysfunction in MS may not only be a consequence of the disease, but may in itself affect the course of MS.

Long-term transvenous temporary pacing with active fixation bipolar lead in the management of severe autonomic dysfunction in Miller-Fisher syndrome: A case report

Management of severe autonomic dysfunction in patients with Guillain-Barre syndrome (GBS) or its variant Miller-Fisher syndrome (MFS) include placement of permanent pacemaker. We report a case of MFS with severe bradycardia and asystole treated initially with an external permanent (temporary-permanent) pacemaker with a transvenous, active fixation right ventricular lead placement as a "bridge" to permanent pacing.

Small fiber neuropathy: a common and important clinical disorder

Small fiber neuropathy (SFN) is a neuropathy selectively involving small diameter myelinated and unmyelinated nerve fibers. Interest in this disorder has considerably increased during the past few years. It is often idiopathic and typically presents with peripheral pain and/or symptoms of autonomic dysfunction. Diagnosis is made on the basis of the clinical features, normal nerve conduction studies (NCS) and abnormal specialized tests of small nerve fibers. Among others, these tests include assessment of epidermal nerve fiber density, temperature sensation tests for sensory fibers and sudomotor and cardiovagal testing (QSART) for autonomic fibers. Unless an underlying disease is identified, treatment is usually symptomatic and directed towards alleviation of neuropathic pain.

Central blood volume influences sympathetic sudomotor nerve traffic in warm humans

The objective of this study was to test whether changes in central blood volume can induce reflex effects on sweating. Multi-unit skin sympathetic nerve activity (SSA) was recorded from the posterior cutaneous nerve of the forearm or radial nerve branches in 11 healthy volunteers. Skin electrical resistance and skin blood flow were recorded in the area innervated by the impaled nerve fascicle. Sudomotor nerve traffic and sweating was induced by whole body heating. Lower body negative pressure (LBNP) and tilting (30 degrees head up) was used for blood volume displacement from the chest to the lower body. Low levels of LBNP (5 and 10 mmHg) had no effect on blood pressure, heart rate or skin blood flow but induced a prompt inhibition of SSA and a reduced number of transient skin resistance changes (n = 9), both rapidly returning to control levels after cessation of LBNP. Quantitatively, the effect was similar at both levels of LBNP. Head up tilting also reduced SSA (n = 3, 19 tilt manoeuvres). A capacity for mental stress-induced SSA increase remained during LBNP. Spontaneous fluctuations in blood pressure did not affect SSA, arguing against arterial (high-pressure) baroreceptors modulating SSA. Consequently, the present results indicate that unloading of cardiopulmonary (low-pressure) volume receptors reduces sympathetic sudomotor nerve traffic and sweating in warm subjects. It is suggested that the reflex contributes to counteracting hypovolaemia.

Disorders of the autonomic nervous system: Part 1. Pathophysiology and clinical features

Autonomic dysfunction may result from diseases that affect primarily either the central nervous system or the peripheral autonomic nervous system. The most common pathogenesis of disturbed autonomic function in central nervous system diseases is degeneration of the intermediolateral cell columns (progressive autonomic failure) or disease or damage to descending pathways that synapse on the intermediolateral column cells (spinal cord lesions, cerebrovascular disease, brainstem tumors, multiple sclerosis). The peripheral autonomic nervous system may be damaged in isolation in the acute and subacute autonomic neuropathies or in association with a generalized peripheral neuropathy. The peripheral neuropathies most likely to cause severe autonomic disturbance are those in which small myelinated and unmyelinated fibers are damaged in the baroreflex afferents, the vagal efferents to the heart, and the sympathetic efferent pathways to the mesenteric vascular bed. Acute demyelination of the sympathetic and parasympathetic nerves in the Guillain-Barré syndrome may also cause acute autonomic dysfunction. Although autonomic disturbances may occur in other types of peripheral neuropathy, they are rarely clinically important.