Chapter 37

Painful polyneuropathy is a debilitating neurologic problem and frequently a challenging therapeutic management issue. Difficulties in managing patients are too often the result of poor understanding of their problem on the part of the treating physician. Many physicians assume that there is no need to work up neuropathy because the final outcome is likely to be an idiopathic, axonal disorder for which there is no effective therapy. In fact, many neuropathies are responsive to immunosuppressive therapies. Although responses to such therapy constitute the minority, they should be vigorously sought before telling patients there is no treatment for their progressive disorder. In many cases, treatment of the polyneuropathy also leads to improved pain control; however, pain is often a primary issue in and of itself and must be treated irrespective of the potential for improvement of the underlying polyneuropathy. In these cases, pain management specialists may work in concert with neurologists to provide a comprehensive treatment approach.

### Clinical Issues in Polyneuropathy: Introduction

The first step in developing a rational approach to patient management is obtaining a working knowledge of the underlying disorders that fall under the category of neuropathy. Although it is often used loosely to refer to polyneuropathy, the term neuropathy is actually not specific and implies any peripheral nerve lesion, focal or diffuse. Classification schemes used widely among peripheral neurologists are based on anatomic and physiologic characteristics of the various disorders affecting peripheral nerves. The use of these classifications is not just an academic exercise but creates a basis for rational decision making in the evaluation and management of patients. The workup and treatment of individual patients with neuropathy must be approached with a basic understanding of the clinical behavior, including the anatomic and pathophysiologic characteristics, of the various neuropathic disorders.

### Classification and Clinical Course

The term polyneuropathy is used to describe a condition that is fairly symmetric and generalized, as opposed to focal neuropathy (mononeuropathy) or multifocal neuropathy (mononeuropathy multiplex). This chapter focuses on the diffuse disorders, including polyneuropathy and multifocal mononeuropathies. These two groups of disorders may be indistinguishable clinically and are frequently accompanied by severe and disabling pain.

Once a disorder of peripheral nerves is suspected, an attempt should be made to characterize the clinical features based on the time course, anatomic distribution, and physiology. Using this information, a reasonable differential diagnosis can be developed, which will determine appropriate further workup and management. This section further discusses the clinical and physiologic features of the diffuse neuropathies; their diagnostic evaluation is covered in the next section.

#### Polyneuropathy

##### Time Course

An important clue as to the etiology of a particular polyneuropathy (PN) is its time course. Generally accepted guidelines would classify a neuropathy as acute (< 3 weeks), subacute (weeks to months), or chronic (> 4–6 months). Notably, neuropathies in each of these categories may be associated with debilitating pain. The typical clinic patient presenting ...

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

## Subscription Options

### AccessAnesthesiology Full Site: One-Year Subscription

Connect to the full suite of AccessAnesthesiology content and resources including procedural videos, interactive self-assessment, real-life cases, 20+ textbooks, and more